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AERONAUTICAL 
JOURNAL. 


A Monthly Ulustrated Magazine devoted 


| 


to all subjects connected with the 


Navigation of the Air. 


EDITED FOR THE 
COUNCIL OF THE ROYAL AERONAUTICAL SOCIETY 
BY 


J. LAURENCE PRITCHARD, Fellow. 


VOL. XXVI. 


| 1922. 


Printed by the Lewes Press, Ltd., High Street, Lewes, and published by the 


Royal Aéronautical Society, 7, Albemarle Street, Piccadilly, London, W.1. 























THE 


AFRONAUTICAL cdOURNAL. 


(FounpepD 1897 in succession to the ANNUAL REPORTS.) 
THE ORGAN OF THE Royal AERONAUTICAL SOCIETY. 


Published Monthly at the Offices of the Society, at 7, Albemarle Street, Piccadilly, London, W.1. 
Telephone: “‘ Gerrard 7373.’’ Telegraphic Address: ‘‘ Didaskalos, Piccy, London.” 


Subscription per annum, £1 12s. 6d.; single numbers, 2s. gd., post free. 
Edited for the Council by J. LAURENCE PRITCHARD, Fellow. 


All communications should be addressed to the Editor. 


JANUARY, 1922. VoL. XXVI. 


Notices of the Royal Aeronautical Society. 


Election of Members. 
The following members were elected at a meeting of the Council held on 
Friday, December 16th :— 
Associate Fellow.—O. E. Simmonds, B.A. 
Students.—A. O. Adams, F. G. Kay, T. H. Smith. 
Members.—V. S. Gaunt, D. Woods Mason, Captain F. H. Parkes- 
Warmington. 


Research in Aeronautics. 


The Council have had several discussions on the question of the furtherance 
of Research, as distinct from ad hoc experimentation in aeronautics ; three special 
meetings having been held for this purpose. As a result it has been decided to 
send a deputation (consisting of the Chairman (Colonel M. O’Gorman), Dr.. L. 
Bairstow, Sir Mackenzie Chalmers, Professor Melvill Jones and Colonel A. 
Ogilvie) to lay the views of the Council before the Air Ministry. The Secretary 
of State for Air has consented to receive this deputation at 11.30 a.m. on January 
17th. 


Airship Records. 


On the closing down of experimentation with airships the Air Ministry, as 
was announced in a previous number of the JourRNAL, decided to present certain 
books of airship photographs to the Society for safe custody and purposes of 
record. These books, to the number of nine, have now been received and placed 
i! the library. They should prove of great interest to members as they constitute 
a complete record, with considerable constructional details, of the development of 
British airships from 1607 to the present date. 


Juvenile Lecture. 


Major D. C. M. Hume has consented to deliver the Annual Juvenile Lecture 
at 3.0 p.m., on Thursday, January 12th, in the Theatre of the Royal Society of 
Arts, John Street, Adelphi. He will talk on ‘‘ Boats that Fly,’ and members 
may obtain tickets for the children of themselves and their friends on application 
to the Secretary. 











2 THE AERONAUTICAL JOURNAL (January, 1922 


Joint Meeting. 

The IMluminating Engineering Society have arranged a meeting at the Royal 
Society of Arts, Adelphi, at 8.0 p.m., on Tuesday, January 31st, when Major- 
General Sir Frederick Sykes will take the chair at a discussion on ‘** The Use of 
Light as an Aid to Aerial Navigation,’’ to be opened by Lieutenant-Colonel L. F. 
Blandy, D.S.O. At the request of the Illuminating Engineering Society this 
Society have agreed to treat this as a joint meeting, and it is therefore hoped 
that as many members as possible will be present. The Secretary will be grateful 
if any member who wishes to take part in the discussion will kindly inform him. 


Associate Fellowship Examinations. 

At a meeting of the Candidates’ Committee held on Tuesday, December 6th, 
1921, a letter from the Honorary Secretary of the Students’ Section was discussed 
and the following recommendations to Council were made. They were subse- 
quently considered by the Council and adopted in toto. 

1. That it be agreed that Students admitted for the regular engineering 
course in a college of university standard shall generally be regarded 
as exempt from Part I. of the examination for Associate Fellowship. 

2. It is not to be understood from the note to the Rule given on page 2 of 

the Rules for Election to Fellowship and Associate Fellowship that 
attendance throughout an approved course of Aeronautics will 
necessarily be counted as equivalent to one year’s experience of the 
science of aeronautics. 

The flying or technical service during the war of any applicant for 
Associate Fellowship must be considered by the Candidates’ Com- 
mittee on its individual merits. This does not make any _ specific 
distinction between flying service during the war and at any other 
period. 

3. It is recommended that the Diploma of East London College in Aeronautics 
and Aeroplane Design be accepted as exempting from the paper in 
Aerodynamics under the Rules of the examination for Associate 
Fellowship of the Society. 


Arrangements for the Month. 


Jan. 5, 5.30 p.m. Lecture by Wing-Commander W. D. Beatty, C.B.E., 
A.F.C., on ** Specialised .\ircraft,’? Roval Society of 
\rts, Adelphi, London. 

12, 3.0 p.m. Juvenile Lecture, Major D. C. M. Hume on ‘* Boats that 
Fly,’ Royal Society of Arts, Adelphi, London. 

»» 17, 11.30a.m. Deputation to Secretary of State for Air. 

.o p.m. Candidates’ Committee. 

30 p.m. Publications and Library Committee. 


wi te 


o p.m. Council. 

5» 19, 5.30 pem. Lecture by Brigadier-General R.  K.  Bagnall-Wild, 
C.M.G., C.B.E., on ** \eroplane Installation,’? Royal 
Society of Arts, Adelphi, London. 

23, 8.0 p.m. Lecture by  Brigadier-General R. K.  Bagnall-Wild, 


C.M.G., C.B.E., on ** Aeroplane Installation,’’ Royal 
Fechnical College, Glasgow. 
», 26, 7.0 p.m. Students’ Discussion Meeting, Mr. Colin Daniel on 


““ Some Practical Points in Fuselage Construction,’’ 
in the Society’s Library. 
» 31, 8.0 p.m. Joint Meeting with the Illuminating Engineering Society. 


W. Lockwoop Marsu, Secretary. 





January, 1922] THE AERONAUTICAL JOURNAL 3 


PROCEEDINGS 
THIRD MEETING, 57th SESSION. 


A meeting of the Royal Aeronautical Society was held at the Royal Society 
of Arts, John Street, Adelphi, on Thursday, November 17th, 1921. Lieut.-Col. 
O'Gorman presided. 

_ The CHaAirMAN said that Colonel Frank Searle, who was to read a paper on 
‘* The Requirements and Difficulties of Air Transport,’’ néeded no introduction 
to the meeting. They were all well acquainted with him by reputation. He 
therefore called on Colonel Searle to read his paper. 


THE REQUIREMENTS AND DIFFICULTIES OF 
AIR TRANSPORT. 


The subject on which | propose to address you to-night is certainly one 
with which this generation is not only rightly challenged, but one with which 
one could almost say that it should be taunted. For nowadays we pride ourselves 
on the fact that no great invention can be universally acknowledged to be suc- 
cessful without its being very rapidly turned to the economic service of mankind. 
But aviation has been a human accomplishment for more than half a generation, 
and so far no aeroplane has earned its cost and keep. 

In the old days, when manufactures were primitive, when accurate machine 
tools did not exist, when very few people were interested or instructed in scientific 
things and no means existed for instructing or interesting the many, it was natural 
enough that great inventions should have been made and then allowed to expire, 
so to speak, without being used. 

My historical friends tell me that the great Marquis of Worcester, in addition 
to many inventions which never materialised, did actually instal a complete water 
supply at his country house, and pumped the water from his well to the tank 
which supplied the house by means of a steam engine. What the Marquis of 
Worcester could do before the end of the 17th century remained unique and 
unimitated until steam was rediscovered more than a hundred years later. It was 
then applied first to actuating machinery, and then to actuating the paddles of a 
ship, and finally to actuating the wheels of a locomotive. But once the first railway 
had been shown in operation, the expansion of the railway service was both rapid 
and universal. Similarly, when it was shown that an internal combustion engine 
could be mada to drive the wheels of a car for use on the roads it was a compara- 
tively short time before the progress of the automobile industry was limited only 
by the time it took for manufacturers to learn the business of engine and car manu- 
facture. But it is not very far from twenty years now since the first aeroplane 
propelled by an internal combustion engine was made to fly. The science and 
the art of aviation received an incredible impetus during the war, and now after 
three years of peace we have sorrowfully, and perhaps shamefacedly, to acknow- 
ledge that we have not vet overcome and mastered the problem of serving mankind 
by air transport. But, like every other phenomenon, at first glance startling, 
there is an explanation of this failure, or if you prefer to call it so, the very qualified 
success of civil aviation. It is our business to end this failure, to complete this 
success; and I suggest that the right. way to begin is to visualise as clearly as we 
san what are the essential characters of the problem, because when we have 
analysed and stated these we shall see clearly what the obstacles are to their being 
practically met. 








4 THE AERONAUTICAL JOURNAL (January, 1922 


These requirements are obviously of three kinds. First there are those proper 
to the vehicle you propose to employ; these group themselves naturally into the 
requirements of the engine, as a source of power, and the plane, both as a device 
for rising into the air, staying in the air, and descending from the air to the land 
it: a satisfactory way; and as a commodious and pleasant vehicle for the accom- 
modation of travellers. Next, bearing in mind that it is a question of transport 
we are considering, there are all the problems involved in bringing travellers from 
their homes to the flying machine before it starts, and delivering them from the 
flying machine, after it has arrived, to their final destination. And lastly—and it 
is these requirements which govern the whole problem—there is the question of 
giving that rapidity and certainty of service to the customer at a price which he 
recognises to represent the advantages offered, and this without the apparatus 
and the organisation costing more than the travellers are able to pay. Stated in 
another way, then, the requirements fall into three groups which should be called 
the technical group, the organisation group, and the economic group. 


Now it is my belief that all these requirements can be met, and I base that 
belief on a considerable experience of transport in other fields, and by some experi- 
ence, not long but very instructive, in the field we are discussing to-night, and as 
I have suggested, the first condition is to state what the requirements are, and 
from these we shall see from past experience why they have not been met before. 

The ideal aeroplane for civil transport must consist of an engine on which 
the undertakers of the transport service can rely, not only for steady work, but 
for long work at a reasonable maintenance cost. The vehicle it propels must take 
the maximum load with the maximum comfort, the limitation in each case being 
the speed, certainty and safety, without which air transport can never become a 
commercial success. And the cost and upkeep of both must be reasonable. 

Our three vears’ experience of civil flying since the war show us that there is 
not in universal use to-day the engine which meets the requirements I have set 
out. The explanation is not so much that these requirements have not been under- 
stood as that at the time when civil aviation became for the first time a possibility, 
the argument for experimenting with makeshift gear was irresistible, the attitude 
of directors and others in aircraft manufacturing firms soon after the time of the 
Armistice when they, in moments of apprehension, turned their minds to air 
transport. This apprehension must have been genuine-and severe, knowing that 
the Government aircraft orders were ceasing and that something would have to 
be done, and done quickly, if the huge factories were to exist even on a much 
smaller scale. 

When some of these firms turned their energies to aerial transport one had 
got to visualise the composition of these companies in order to see whether they 
were in any way competent to carry through to successtul issue aerial or any other 
form of transport. 

It must be borne in mind that at the beginning of the war the science of 
aviation was so young and the necessity for aircraft so great that both the manage- 
ment and the technical staffs of aircraft manufacturers were intensive productions, 
and from the beginning of the war to the end of it, were fostered on expensive 
lines; whilst at the same time the managements and technical staffs of other and 
more slowly-developed industries were all fully occupied and necessary in their 
own particular sphere. 


Another very great factor was that these intensive staffs were reared in an 
atmosphere of forced production with very little regard for economy either in 
personnel or material. It is not very surprising, therefore, that when they made 
their momentous decision to go into aerial transport they went ahead on what to 
them was their ordinary business methods; namely, of extravagance in men and 
material, and, instead of enlisting new men and material, carried on with what 
existed at the moment. 





— wa 


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January, 1922] THE AERONAUTICAL JOURNAL a 


Their first thought seems to have been to transfer war machines and men to 
the transport companies, the majority of both being not only unsuitable but detri- 
mental to the very progress they were so anxious to foster. The designers, too, 
who are the aerodynamic and theoretical people on whom we rely for flying 
efficiency, had not the advice of people with practical transport experience to 
guide them as to the requirements of a commercial transport service; they had 
only the advice of those whose experience was limited to war flying. The tendency 
ct the designers themselves, quite naturally, was also influenced by their experience 
having been gained, one might almost say entirely, in the design of machines 
for war purposes. My critics will no doubt say that it is easy to be wise after 
the event, but if we examine the problem they had to solve it will be admitted that 
any authority on transport for profit would have provided different men and 
different machines. 

A transport man would have at once gone into the daily overhead charges 
per machine, in which would be included such ordinary items as depreciation, 
insurance, interest on capital and management and office charges, and these, plus 
the net flying cost per mile, would give clearly the number of miles per day per 
machine which have to be flown in order to break even, assuming the average 
normal load of other forms of transport. 

In spite of the ease with which such figures could have been obtained, at the 
time I went into business (which was twelve months after air transport had been 
established) I was told by one cf the highest authorities on flying—a man who 
had gained a very high reputation during the war, but who had only war experi- 
ence and no commercial experience—that an aeroplane could only fly 250 hours a 
year. This means approximately 7o miles per day; therefore, at 50 per cent. 
load, a four-seater machine, charging 1s. 6d. per mile per passenger, could not 
possibly earn sufficient to pay its overhead charges—this figure represents an £718 
fare to Paris, at which price passengers could not be cbtained. Nor could they 
be obtained at £715. At £10 they began to appear in small numbers, and at £6 
we find signs of real interest. In addition to this, not having worked out and 
appreciated these fundamental figures, firms employed a far greater number of 
machines than were necessary to obtain even the above unsatisfactory figures. 
On the other hand, one must not lose sight of the fact that but for their heroic 
efforts and the colossal loss of their, and other people's, money, civil aviation 
would not be where it is to-day; though had they found the money and given 
the problem to some firm who had been successful for many years in mechanical 
transport, it could have been to-day on a much sounder basis. than it is. 

The operation and maintenance of their machines was carried on with 
lamentable lack of knowledge. For instance, whilst they employed a vast number 
of machines for the services which were maintained and on which the overhead 
charges went on daily, there was a very serious shortage of spare parts and spare 
engines, and, in consequence, machines were lying idle whilst their engines were 
being repaired, which meant that they were not only losing their earning capacity 
but that the overheads of about £4 per day per machine were going on for two 
or three weeks. 

Again, little or no equipment was provided for doing repairs and inspections 
expeditiously, whereas a small capital outlay in this direction would have saved 
hundreds of pounds in labour. 

Again, none of the executive heads of the concerns held ground engineers’ 
tickets as granted by the Air Ministry. These were all held by mechanics, so 
the decision as to fitness or otherwise of a machine was in the hands of the 
workmen, whose word was final. It should, of course, have been imperative that 
those in charge held the necessary qualifications required by the Air Ministry. 

In addition to this, the facilities for carrying on one’s work at Croydon were 
very poor since in many cases the machines of various companies were mixed up 











6 THE AERONAUTICAL JOURNAL (January, 1922 


in one shed and machines had to be constantly moved about in order to accom- 
modate others arriving at cdd times. — Also, no bulk petrol storage tanks were 
provided, which meant that big quantities of petrol had to be man-handled in 
two-gallon tins, whereas a little forethought would have saved all this labour and 
at the same time saved 1$d. per gallon on the price of the petrol which, considering 
the quantities consumed by aeroplanes, amounts to a considerable sum at the 


end of a year. The Air Ministry had considered the bulk storage question, but 
had shelved it owing to the fact that during the next three years they might 
have had to shift it to a more permanent spot. | mention this to show that the 


people handling air transport at this time were lacking the commercial touch, since 
in this case an expenditure of £500 would have saved £750 the first vear. 

Again, at this period the meteorological information was mostly too late and 
too meagre to be of real service, and the wireless installations were very ineffective. 
It was the same with the Air Ministry as it was with the companies—they had 
not the experience to differentiate between the essentials and non-essentials of air 
transport, and consequently often spent money unwisely from this standpoint. 
One must admit that the Air Ministry worked exceedingly hard in the interests of 
air transport, but they were guided by chance and not by experience, and | feel 
sure there must have been someone in the marine or road transport business who 
could have given them the guiding principles of their own business which would 
have been useful in air transport. 


In the past the air transport companies were in the habit of carrying all their 
passengers and goods to and from the aerodrome (which cost them over 4:1 per 
head or 10 per cent. of the fare), and also of giving 10 per cent. commission 
to the various travel offices for booking a passenger by air. This again is 
excessive, and such offices should not expect more from air companies than from 
railway or steamship companies ; in fact, in order to foster the business, they should 
be prepared to accept less. It is these heavy unnecessary charges that must go, 
otherwise air transport must fail. 


Now with regard to air passenger organisation. The circumstances proper 
to all other forms of transport are proper to transportation by air. Nobody would 


make a success of the finest and fastest Atlantic steamer service that science can 
conceive or genius supply if the rapid and luxurious ships, we suppose in existence, 
started from some inaccessible port in England and arrived at some destination in 
America extraordinarily inconvenient to those who wish to go to the centres of 


population. It is not a counsel of perfection; it is simply axiomatic that the 
aeroplane, like the express train and like the steamship, is not a_ self-sufficient 
vehicle as, for instance, is the motor car. To get to the train you have to use 


a carriage or car to take vou to the station; when you arrive at your train 
destination vou have to have another vehicle to take you home. If you leave 
England and live in London vou have to take a train to the port from which 
the ship starts. If you arrive in New York and vour destination is Chicago, you 
have to take a train from New York to Chicago. In the first case the carriage 
and the cab, and in the second case the train service, are integral factors in the 
journey. Now so far as civil aviation is concerned, we have neither in England 
nor in Paris a starting and landing point for aeroplanes which is served by cheap, 
commodious and punctual train services; for that matter they are not 
served by train. services at all. Secondly, to go back to our first 
comparison. If you are going from London to Liverpool, and thence from Liver- 
pool to New York, vou can drive in a closed carriage to Euston where there is a 
comfortable station and waiting rooms affording complete protection from the 
weather, and when you get to Liverpool the train runs alongside the steamer, and 
you go along a covered gangway to the ship. It is only a few years since the 
trains started running alongside the ships at Liverpool and other ports, but it was 
realised what an important advance it would be, and how much such a service would 
add to the comfért of passengers. You can hardly expect the air service to be 





January, 1922] THE AERONAUTICAL JOURNAL a 


as comfortable as the train service until some such amenities as these exist at the 
starting and landing place. At present there is no means of getting to the aviation 
grounds at Croydon at all except by car, and arrived there, there are neither 
waiting rooms nor conveniences of any kind for the comfort of the passenger, 
and he has to walk many hundreds of vards, often through slush and mud, before 
he reaches the vehicle in which he is to spend two hours nursing his sodden feet 
to Paris. 

I mention only the rudimentary shortcomings of the air service as it exists 
to-day, but obviously we cannot hope for flying to be a regular feature of normal 
travelling life until this form of travelling includes—I will not sav the luxuries— 
but these mere mitigations of discomfort which we all take for granted when 
travelling by train or steamer. 

And here another point must be considered. One of the fundamental troubles 
in connection with flying to-day is not only that the traveller has none of the 
comforts and conveniences that he is accustomed to in cther forms of travelling, 
but he is put to enormously greater expense because of the absence of facilities 
which surely could be supplied without undue cost or risk. It is, in my opinion, 
simply absurd that there should not be a regular service of trains to a platform 
running alongside the plane at the aerodrome, so that within a quarter of an hour 
of saying good-bye to his friends in London the traveller should be seated in his 
aeroplane and ready to start; and that there should not exist in Paris a service of 
exactly the same nature. Apart from all other question, this provision for the 
comfort of the traveller is an indispensable condition cf successful commercial 
flying. 

The question at once arises as to who is going to provide the railway facilities 
to the aerodrome. In the first place, an aerodrome should not be chosen which 
is cut off from the outer world either by distance or lack of communication, and 
if the ideal aerodrome necessitates such glorious isolation, then the Government 
must subsidise some railway company to provide the necessary connection. But 
for the Government to choose an isolated spot for an aerodrome and then subsidise 
air transport companies by a subsidy on gross takings from passengers who cannot 
get there is, of course, absurd. 

Now when it comes to the economic side of flying, this obviously is a question 
of balance between receipt and costs. |The circumstances that define the most 
economical form of ship or train or motor car are the same as those that define 
the desired features of an economical aeroplane. The speed must be such as to 
give an overwhelming advantage over any other form of locomotion. But it 
must be speed consistent with carrying a considerable load at a running cost which 
is not excessive, and it must be speed that does not demand either excessive first 
costs of engine and aeroplane or excessive upkeep. On these points we have learnt 
a great deal in the last three years, but I venture to say that we should have 
learnt more if the public authority for dealing with flying had been composed of 
individuals more familiar with the problems as we see them in this room, and 
less influenced by experience and problems of a totally different nature, namely, 
those propounded by aviation during the war. 

The position of the Air Ministry in air transport is a most important question, 
and one which ought to be cleared up at once. At the present moment it combines 
the equivalents of Municipal Authorities, Trinity House, the Board of Trade and 
Lloyd's, and I will deal with the analogous functions in this order. 

In my opinion the Air Ministry must for the time being continue to act as 
Municipal Authorities in the way of developing aerodromes, and as Trinity House 
in regard to navigation, but in carrying out these duties every effort should be 
made to improve the foreign liaison with our neighbours and persuade them force- 
fully to provide the same facilities on their customs’ aerodromes as we provide 
on ours, as well as equal lighthouses on the routes. France has had far more 
money voted to civil aviation than we, and yet Le Bourget and St. Inglevert 








8 THE AERONAUTICAL JOURNAL (January, 1922 


are disgracefully organised. | The London aerodrome should be at least 1,200 
yards square, and the adjoining land should be acquired and let out for grazing 
so as to provide a good take-off in every direction and provide good re-landing 
possibilities during that period of flight just after taking off. The sheds should 
be on the lee-side of the aerodrome to prevailing winds so as to minimise taxi-ing, 
which is a serious cost, and one which was given very little consideration during 
the war by reason of the fact that it was not necessary to count the cost; but 
| have no hesitation in saying that five minutes of taxi-ing does more damage 
to a machine than ten hours’ flying. Separate accommodation should be provided 
for each company, with a common shed for ‘‘ casuals.” 


If the Air Ministry are to continue to act Trinity House, as they must, 
they must accept the responsibility for persuading adjoining countries to do like- 
wise, so that night flying may be made as safe as daylight flving. On the Paris 
route there should be two lighthouses between Croydon and Lympne, and three 
or four between Paris, La Plage and Le Bourget. 

In regard to the Air Ministry acting as the equivalent of the Board of Trade 
and Lloyd’s in marine matters, I have no objection to their doing the former's 
equivalent duties, but with regard to the latter I do feel that the time is here 
for owners, builders and underwriters to get together and form some sort of 
Lloyd’s Committee so as to keep the Air Ministry advised of their requirements. 
The question is one of the utmost importance. The Air Ministry has not yet 
the complete confidence of business men, and it is necessary for them to have 
some reliable source of information as to what regulations are necessary for the 
protection of all their interests. 

There are some very brilliant young men at the Air Ministry who are most 
thorough and conscientious in their work; but when one deducts their negative 
commercial and economic experience of the war, one finds that experience with 
them cannot be expected. And in a few cases, after deducting their negative war 
experience, they could not have had more than the meagre engineering or technical 
training of an apprentice or pupil. 

These men in many cases have the power to dictate as to design and details 
of operation, and companies have no appeal from their considered opinions which 
are invariably based upon war experience and R.A.F. training. Every official in 
the technical branches of the Air Ministry should be an engineer of good training 
and undoubted experience excluding his war service. 

I should also like to mention the examinations for ground engineers. These 
are verbal examinations, and are therefore the most difficult to organise, and 
from what I have seen, they have a tendency to follow that unsound policy 
adopted temporarily years ago in some of the Board of Trade examinations for 
the marine engineers’ tickets—it is that of trying to “‘ catch ’’ the applicant by 
trick questions instead of thoroughly ascertaining his education, experience and 


knowledge. An example seen in the Air Ministry was a_ stretching screw—or 
turnbuckle—which had both ends screwed to the same hand; and the applicant 
was asked to examine it and state where it was faulty. I suggest that such 


‘* catches ’’ are not a reasonable test either for education, experience or knowledge, 
which all goes to indicate that the examiners do not quite realise the essential 
qualifications of the holder of such a ticket, and I consider that the examination 
papers for the applicants for these tickets should be laid down by the committee 
to which I have referred. 

The wireless on this side is good but stronger liaison is required with the 
Continent, where the wireless service even yet, after two vears, is still practically 
useless, and direction finding must be developed to perfection along the whole 
of the Paris route without delay. 


Some organisation would appear to be necessary for flying in mists and 
clouds, in that.on the organised routes machines flying in opposite directions 








li a ens 


13" 


1S 


January, 1922 THE AERONAUTICAL JOURNAL 4 


should have different ranges of altitudes. This, I think, is where the Committee 
previously referred to should make some recommendations, and it is most impor- 
tant that the meteorological office should collect information from machines in 
the air and distribute it within a few minutes, when the information would be of 
vreat practical value. 

The time must be fairly near when emergency landing grounds will not be 
required, but I think that for two years more the Air Ministry should maintain 
two landing grounds between Croydon and Lympne, and they should insist upon 
the French providing one near Abbeville and another near Beauvais. 

I will now turn to the subject of aeroplanes and engines and the first remark 
1 will make is that manufacturers must guarantee their productions for a reason- 
able period after delivery; the guarantee must include the risk of parts having 
to be re-designed owing to faulty design in the first place. It is no use a manu- 
facturer selling a batch of engines and after three months admitting that the 
compression is too high and offering to supply new sets of pistons for £60 or 
£100 per set; and then after another three months admitting that the connecting 
rods are of unsuitable design and refusing to replace them except at the cost of 
over £200. I can only say that those manufacturers who are not prepared to 
guarantee their goods for the purpose for which they were purchased will be left 
without orders as soon as opportunity occurs. I] am glad to say that there are 
signs of some manufacturers of machines taking some of the responsibility for 
their design. 

In the interests of aircraft manufacturers I should like to sound a modest note 
of warning to the effect that they should not let history repeat itself by forcing 
the air transport companies into manufacturing their own machines, due to high 
prices, as has been the case with other forms of passenger transport. They must 
bear in mind that it is difficult for a manufacturer to retaliate, since he must make 
his machines suitable for as many markets as possible and therefore cannot 
specialise. 

To my mind the price of the present day machine is altogether too high, 
although efforts seem to have been made to reduce the price. With the present 
wood construction, which still presents outstanding advantages, I am sure a lot 
more can be done. The all-metal machine seems as far off as ever, and I doubt 
very much whether it will ever be nearer than a composite of metal and wood. 

Notwithstanding the many times I have expressed my candid views on such 
questions as engine installation, cowling, controls, etc., I find very little improve- 
ment to-day in most of the latest designs of aeroplanes; and the war-type practice 
in many Cases appears to be very deep rooted. 

Also there still appears to be a strong tendency in design to put appearance, 
in the way of pleasing exterior lines, before utility and service. In the design of 
the various metal clips and fittings on our aeroplane I plead for the use of 
ordinary commercial mild steel plate, which after working requires only the crudest 
annealing. In speaking of the propeller, I think that it is time a weather-proof 
propeller was in transport service. A metal propeller fills the bill if it does not 
weigh too much or absorb too much power, but I think we are on the wrong lines 
still trying to use a metal tip on to a wood propeller, which twists and stretches 
all the time it is working. 

The continued use of the pneumatic tyre surprises me. I feel sure that a 
solid-tyred wheel can be designed which will transmit safely all the shocks and 
forces to the undercarriage damping gear, and yet not be too heavy. The Germans 
used wooden tyres during the latter. part of the war. My critics will now tell me 
that they soon changed to pneumatics whenever they could get them. This is 
true, but one must bear in mind that the German undercarriages are not as shock- 


absorbing as ours, and the fact remains that the German wheels stood up very 
well. , 








10 THE AERONAUTICAL JOURNAL (January, 1922 


On the subject of engines, my chief complaint is the cost of the engine and 
spare parts. I give a few examples and comparisons. One of the best known 
modern aeroplane engines costs £6,000 per ton. Complete machinery, including 
hoilers and all auxiliaries, for a 35-knot destroyer costs only #200 per ton. 
Complete machinery, including boilers and all auxiliaries, for a 25-knot cross- 
channel vessel costs about £90 per ton. I am told that the reason for the high 
cost of the aeroplane engine is due to the expensive material and the still more 
expensive testing and heat treatment. If this is a fact then we must sacrifice 
20 per cent. of the engine weight and get down to an article which will appeal 
to the commercial engineer, an engine which will run 30,000 miles without over- 
haul, and I am sure that one giving such results could soon be evolved if the 
tvpe tests for these engines were made on the time table basis. I suggest 
three 3-hour stretches a day with one hour’s interval between, during which time 
the engine must not be touched; the engine to start at the same hours every day 
until 300 hours is reached, ten minutes being allowed before the time table time 
for starting and warming up to full power. The three-hour stretches should 
comprise 10 minutes at the start at full power, then 75 per cent. full power for 
the remaining 2 hours 50 minutes. The engine that can stand up to this test, 
even if its price is not lower than say 25 per cent. below present prices, will fill 
the bill. 

In conclusion, I do trust that those whom I have criticised will accept such 
criticism in the spirit in which it is made and as coming from one who has had 
some knowledge of other new forms of transport from the operator's point of 
view, and in consequence has suffered agonies from the official side and the manu- 
facturer’s side, and I wish to see air transport relieved from as much of that 
nerve-racking experience as possible. My final advice is that vou should make 
vour objective the success of aerial transport, forcing through the essentials and 
leaving the non-essentials until the industry is firmly established. 


DISCUSSION. 


The CHAIRMAN said that at the appropriate moment he would ask the meeting 
to pass a hearty vote of thanks to Colonel Searle, but he thought they had bette: 
discuss the paper first. He opened the discussion by reading a communication 
which had been received from Captain « 


mace ling ais ; . “ee ‘it 
Havilland and he was sure they would 
like to hear what Captain de Havilland ‘A 


e 
| 
had to si 


I have read with much interest Colonel Searle's clear and forceful paper. 





In the main I agree with his remarks. There are a few points connected 
with design on which I would like to comment. One of the chief difficulties 
of designing firms has been the time factor. After the Armistice most 


designing firms were either disbanded or had to reduce their staffs con- 
siderably, and could only eXIst on Government orders for military machines. 


They could not atford to lav down commercial types on the chance of an 





order, and it was only a few weeks ago that there was anv certainty of orders 


for commercial machines. And these machines have to be turned out by 
next spring, embodying all those ideal points mentioned in Colonel Searle’s 
paper. Under these conditions it would be very unwise to strike out on any 
new line of design. \ machine embodving new features requires at least a 


vear and probably more before it can be called * tried out.’ 

I entirely agree with Colonel Searle on the matter of speed and 
incidentally it is the fact that a high speed machine is cheaper in first cost 
and maintenance. The landing difficulties of high speed machines have been 
enormously exaggerated, as proved from actual experience. 


I agree with Colonel Searle that pneumatic tyres are undesirable. I 
also fully éndorse his remarks about metal constructien. I can see nothing 





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— 


J 


January, 1922] THE AERONAUTICAL JOURNAL 11 


but trouble and expense with metal machines as at present designed and 
firmly believe in the future of wood construction. We want to break away 
from a lot of convention in construction, and the Air Ministry can help by 
not adhering to wartime restrictions (such as the absolute prohibition of piano 
wire, the laying down of close restrictions on petrol and water systems). 
The specifications for certain materials, such as three-ply and fabric, should 
be made easier, and every facility should be given for expansion of ideas on 
design. All this will help to cheapen machines. 


‘* The only pessimistic remark in the paper from the public’s point of 
view is that * The ideal aeroplane for civil transport must consist of an engine 
on which the undertakers of the transport service can rely.’ ”’ 


Mr. Hanpiry PAGr said he had read through the paper, like everyone else, 
with intense interest. He had thought of opening his remarks by saying, ‘* Now 
we know all about it,’ because, if he might say so without offence to the lecturer, 
it was easy to be dogmatic in what are the requirements of civil aviation after 
one had found them out. One must carry one’s mind back to the early days of 
civil aviation when the mere thought of running continuously, day by day, no 
matter what the weather was, between London and Paris, was jeered at by a very 
large number of people. The initial problem was the serious difficulties in aero- 
dynamics which had to be got over before the super-men, who had had experience 
in the transport world, could make the undertaking the success which they all 
looked for, should he sav next vear? (laughter). He had been extremely 
interested, apart from this paper, in reading in ** The Times *’ a report of General 
Trenchard’s speech on civil aviation and whether, in fact, civil aviation was any 
good to any country. General Trenchard had looked at the matter purely from 
the point of view of one who was charged with the very high duty of defending 
our shores against invasion, and he had said that civil aviation, both from the 
point of view of cost and pilots and men and flying hours, was very expensive 
compared with the additional squadrons which could be given if the money had 
been spent on territorial forces. That seemed to him (the speaker) an extra- 
ordinary view, because if that was going to be the case, then civil aviation must 
always be looked at as a background for the military side. He himself was one 
of those people who thought that the military side of aviation was something 
which was in the background of civil aviation. The first thing was that the 
small amounts spent on civil aviation provided just that little difference between 


big volume of receipts and the slightly bigger volume of expenditure which 


occurred in the initial stages. The money wisely spent would thus produce far 
better results in that particular direction than on a military objective only. Civil 
aviation might take a most useful analogy from the animal world. He was in- 


formed that of all animals the human infant was the most helpless, but when 
grown and of full size it had the greatest power of vision and the greatest intelli- 
gence of all animals, but it required a lot of money in the early stages, and the 
more sick the infant was, the greater the cost. There was a very good analogy 
in that for civil aviation. In the early stages it was very costly. If they did not 
treat it properly and it got sick it became more costly, and the only way was to 
treat it properly, and then it would grow up and, by its intelligence, far surpass 
al! other means of transport. 


He had been extremely interested to read the different qualities which Colonel 
Searle laid down for an aeroplane which would be successful for air transport. 
It had been his privilege during the last few days to sit in the conference which had 
been taking place in Paris and listen—and sometimes understand—what was said, 
and the conclusion he had come to was that the most successful way of popularising 
civil aviation was by flying. Far more progress would be made by experimental 
research through continued flving and finding out the difficulties and the things 
that had to be overcome than by laying down too definitely at an early stage 








12 THE AERONAUTICAL JOURNAL (January, 1922 


what we must do and what we must not do, because he felt the time was hardly 
ripe yet when we could be too definite in our specifications. In saying that, how- 
ever, he did not wish in any way to detract from the excellent and lucid way in 
which Colonel Searle had put forward certain requirements that were necessary 
and essential to air transport. 

Colonel T. F. BrigGs, called on by the Chairman, said he regretted that he 
had not received an advance copy of the paper and was not, therefore, in a position 
to discuss it very fully. 

The CHAIRMAN reminded the members that if they would send a postcard to 
the Secretary an advance copy of the papers would be sent to them. Not being, 
unfortunately, a rich society, they could not send advance copies around wholesale. 


Colonel BriaGs said the only point that occurred to him was that of silencers, 
which ought to be given consideration to from the point of view of the comfort 
of the passengers. 

Captain GILLMAN, referring to the mention in the paper of the desirability of 
a committee of Lloyds being formed, said that such a committee was formed in 
June, 1920. The members of that committee were composed of underwriters of 
aviation risks, members of Lloyds’ Committee and representatives of aircraft con- 
structors as well as a representative of air transport companies. The committee 
had been trying, as much as it could, to make the conditions of flying in civil 
aviation safer and it certainly had met with a fair amount of success. It had 
sent up various reports to the the Air Ministry and it had also passed certain 
resolutions which had been circulated, and it was hoped, later on, that the scope 


of its work would become more and more wide. Among other thing's, it had 
created a register of aircraft and pilots; this was the beginning of a register 
which would resemble Lloyds’ Register of Shipping. At the present moment this 


register consisted of books which merely stated facts about machines without 
any pretence of classification. Classification had not been tackled because it was 
a very difficult subject and had got to be approached very carefully, and the com- 
mittee would much rather go to work slowly but surely. With regard to any 
recommendations by the committee, it seemed to him that it would be very useful 
if there was a higher committee formed, which would be a Supreme Council on 
aviation, composed of Air Ministry officials and representatives of aircraft manu- 
facturers, air transport companies and members of Lloyds. This committee, he 
suggested, should have plenary powers to pass rules and regulations and make 
laws to govern civil aviation. It was not satisfactory that when official bodies 
like the S.B.A.C. and Lloyds send up resolutions, there should be another body 
which could veto them entirely if it wanted to. Such a system was not right, 
and corporations like Llovds and the S.B.A.C. should have some say in the 
matter afterwards, because very often—he did not say it had happened, but it 
was quite possible—an important resolution might definitely be shelved. With 
regard to railways, Croydon seemed to be a favourable place to start from, and 
it the point of departure was moved to the north side of the aerodrome, near the 
tram lines, it would only need a short line run from Waddon station to the point 


of embarkation. As as alternative the L.B. and S.C. Rly. could stop its trains 
at Waddon at certain times and a conveyance could be provided to take the pas- 
sengers from the train to the point of departure. As regards grazing on the 


aerodrome, if ground was to be looked upon as an emergency landing ground, it 
was very undesirable to permit grazing on it as more than one accident had 
happened through an aeroplane running into an animal grazing in a field when 
it was forced to land. If they were going to have land for this purpose, then it 
should be kept clear for machines. Another point was taxi-ing across the aero- 
drome. He did not see why a hard track could not be laid down round the 
aerodrome. It ought not to be a very expensive affair; it need not be ferro- 
concrete but’ just sufficiently hard to carry the heaviest machine, and then the 





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January, 1922] THE AERONAUTICAL JOURNAL 13 


machines could easily be run along the track to a suitable position from which 
they could take off into the wind. There could also be something in the nature 
of an electric trolley, to haul the machines tail first to the desired spot. After 
landing, machines could in the same manner be hauled back to the sheds by 
the trolley. It would save all vibration and a great deal of petrol and oil. He 
asked if Colonel Searle would give his opinion as to the possibilities of air trans- 
port in Great Britain, including Ireland. 

Colonel OGILviz, whilst endorsing almost everything Colonel Searle had said, 
thought there were one or two points at the end of the paper on which questions 
might be raised, especially as regards the figures as to the cost and weight of 
engines and the possibility of increasing the weight by 20 per cent. The cost 
figure given was £6,000 per ton. He did not know of any engine in service 
which cost that, if, as they should, they considered with the engine such parts 
as the radiator and propeller. On that basis it would be found that the figures 
given in the paper were not at all correct. It would be found that one very good 
engine at the present time would come to about £2,000 per ton and another 
#:4,000, and these were both engines which were being used at the present time 
for civil aircraft transport. 


The CiamrMan asked how adding the radiator diminished the price per ton. 


Colonel OGILVIE replied that while considering the weight of the engine they 
must think of it as a complete engine unit suitable to function as the power plant 
of the aeroplane and not simply as the engine stripped of all the parts such as 
radiator, which were really part of it. The addition of these accessories did not 
really make a great deal of difference and might make the figure £2,500 instead 
of £2,000 for the cheaper engine he had mentioned; £6,000 per ton was 
altogether a terrific price. 

He would also like to dispute the ** cost per ton ’’ way of looking at engines. 
What was wanted was an engine as light as possible and not as heavy as possible. 
On the ** cost per ton *’ basis it would, of course, be a lot cheaper per ton to double 
the weight of the engine with the addition of lead, but this would not make it a 
useful engine. A much better way of looking at engines was on the ‘‘ cost per 
horse-power *’ basis. 

The two engines he had in mind came out at 43 per h.p. in one case and 
#5 per h.p. in the other. He had not got any certain knowledge of the cost of 
a destrover engine plant, but as far as he could find out, it worked out at about 
#4 per h.p., which was something very comparable to aircraft engines. 

The question of increasing the weight of engines by 20 per cent. was a very 
important matter. It was easy enough to say that we would like to have an 
engine which was more reliable and that we could afford to pay 20 per cent. 
more for it, but actually he very much doubted if we could afford it. If they took 
an ordinary machine of the present day and worked out the various percentages 
for the engine unit, the structural unit, the load unit, and so on, it would be 
found that by adding 20 per cent. to the engine unit they would be knocking off 
something like one-third or one-quarter of the available paying load. The load 
percentage was reduced from about 25 per cent. to 18 per cent. and he suggested 
that that was too much to pay. 

Captain Hiscocks, referring to a point made by Colonel Ogilvie that com- 
parison of aero engines with other prime movers should be made on a cost basis 
and not on a weight basis, stated that the cost per h.p. in an aero engine was 
about 45, and that this compared favourably with steam, gas and electric power 
units as well as with petrol engines used for pleasure and commercial vehicles. 

Although at first sight an aero engine looked expensive because its size and 
weight were relatively small, it should be remembered that the materials used 
were the best obtainable, the amount of work done on the parts large, the per- 








14 THE AERONAUTICAL JOURNAL (January, 1922 


centage of scrapped parts high, a large amount of jigs and tools and special 
plant was necessary, and the cost of the experimental work was higher than in 
the case of the manufacture of other kinds of prime movers. 

A manufacturer might easily spend £30,000 to £40,000 developing a design 
of aero engine which theoretically, and on paper, appeared very promising, but 
which when made would not satisfy all the requirements of a successful aero 
engine, and it is probable that only one design in a dozen ever gets home and 
makes a profit. 

The case for the aeroplane manufacturers is somewhat similar, and one would 
like to remind Colonel Searle that for aeronautics to progress and flourish, the 
manufacturer must make some profit as well as the transport companies. 

Mr. GREEN said he came to the meeting knowing little about civil air trans- 
port and had hoped to listen rather than to talk. The lecturer’s interesting paper 
reminded him rather of an incident that occurred during the early part of the 
war, when he was interviewing an official of the War Office in connection with 
an aero engine. ‘This official told him that it was not a bad engine, that it went 
all right, but that it was made of materials that were too difficult to get. What 
he wanted was an engine made of cast iron and not too good cast iron at that. 
This is a really true story and the speaker could not help feeling that Colonel 
Searle was working rather on the same lines. Colonel Searle said we must have 
cheaper and better engines and of course this is what we are trying for. Unless 
all designers were rather stupid, better engines would no doubt be produced in 
time. 

Colonel Searle had put a great many points forcibly and clearly before them 
and the speaker was sure they would all profit by the paper. It seemed to him 
# little dangerous for the lecturer to suggest that we should make heavier engines 
or heavier aeroplanes, or heavier anything else that was used in aeronautics. 
The margin of paying load was now very small, and any little addition, such as 
an increase of 20 per cent. in the weight of the engine, would make it even more 
difficult to make flying pay, even if the engines ran longer without overhaul. In 
the speaker’s opinion development must be in the direction of lighter engines 
and lighter aeroplanes. We should have to go on learning and putting better 
engineering into our work so that we can make a light engine and a light aero- 
plane last a long time, if we were to make an aeroplane service worth while. 


Colonel L. F. R. FELL referred to the author’s remarks on the type test, 


which it was suggested should be made stiffer. The type test had been one of 
the greatest troubles and for a very good reason. The cost of running a type 


test on an engine of about 500 h.p. was something like £20 per hour, taking 
al! expenses in, so that nowadays with the small orders that were coming along 
for aircraft engines it was a large item to have to add to the overhead expenses, 
such as £20 an hour for 300 hours, and that was why it was not really done. 
At the moment, the test was considered to be absolutely as severe as anybody 
could possibly stand. It was now under consideration to make it a 50 hours 
run non-stop, beginning at definite times, but whether that would be agreed to or 
not, he did not know. With regard to modifications, he thoroughly agreed with 
the author about that. He knew the case which was referred to in the paper 
and it certainly was a very bad one, but in future he did not think it could possi- 
bly occur. The engine in question at the time had not passed the type test and 
it only had a limited approval, but since then it had done the test and now was 
approved. In future, an engine that had done the type test could be taken to be 
satisfactory, as satisfactory as it could be made, and we should not have any 
more cases of that sort. _ 


The CnamrMan said Colonel Searle’s objective was to encourage the quick 
‘ransport of persons and suitable goods. This was one of the very big things 
with which the world was concerned. When achieved it would make, as much 





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January, 1922 THE AERONAUTICAL JOURNAL 15 


as the Washington Conference, for the diminution of armaments, since it would 
spread a good understanding amongst peoples. Quick transport, by leading te 
personal contact, overtook misunderstandings and killed them rapidly. It was 
an economical thing for any country to encourage, because it has been proved 
time and again how expensive it is to kill a lie later on, and a cleverly distributed 
lic might mean war. That was a general principle and was among the reasons 
why aircraft transport and travel should be taken seriously by this country. An 
outlay was not necessarily expense—it might be investment—and an investment 
to encourage civil transport by air should be regarded as money utilised in the 
direction of safeguarding peace. He was much inclined to agree with Captain 
de Havilland, where he pointed out that the aeroplane designer had not up to the 
present had a chance of launching a design after thoroughly testing and trying 
it out. He had never been allowed to do what the motor car maker did, viz., to 
test out and eliminate the shortcomings of next vear’s design by a year of 
strenuous use before it was put on the market. The aeroplane had always been 
presented to the user in its crude, raw stage, and that had, in all probability, 
conduced to justify Colonel Searle’s critical attitude in his paper. He was in 
agreement with those who deplored the advocacy of 30 per cent. increase of engine 
weight. To suggest the abandonment of alloy steel was mere retrogression. 
He personally considered that aircraft progress was bound up with the improved 
use of light, strong structural materials and methods—and among these were the 
heat-treated high tensile alloys of steel. Similarly, the basis of aero engine utility 
was lightness, reliableness and fuel economy. Study, research and experiment 
would no doubt distribute the engine’s weight with greater nicety—but the mere 
increase of engine weight could not be regarded as desirable without specific proof 
that a specific excess was needed in a special part. The margin of payable load 
at present was very small and they could not afford to waste any of it. The 
engine was already one-third the weight of the loaded aeroplane and to add 30 
per cent. to the engine would be to eat up 15 per cent. of the paying load or 
alternatively the whole of the calculated profit and civil flying would shut down. 
He sincerely hoped that Colonel Searle would reconsider any such recommendation. 
That was one point of criticism, but it was not, however, meant to be an attack 
on the tenour of what Colonel Searle had said and with which he agreed. He 


would now call on him to reply to the discussion, which had, he thought, brought 
out several points of interest. 





Colonel SEARLE, answering Mr. Handley Page, said there were a lot of 
transport babies at the present moment and they had been through measles, 
scarlatina and other troubles; if they knew when they took on air transport that 
they were like]Jy to have measles, scarlatina and whooping cough, they should 
have taken the ordinary precautions. Instead of that they had nearly killed the 
child. That was his reply on that point. He quite realised the difficulties of 
the manufacturer in getting the ideal machine, but it was the ‘principles of trans- 
port that they must stick to and there were a few fundamental factors which 
they must bear in mind in connection therewith and he would deal with the Chair- 
man’s remarks on that later on. Mr. Handley Page had said that he should not be 
too definite in laying down design; he had laid down no design and did not attempt 
te do so; he had much too little knowledge of the business as far as design was 
concerned, but he had a knowledge of transport and knew what was wanted. 
If transport operators and the manufacturers could get together, he was perfectly 
certain that they would solve this problem, which he admitted was a difficult one. 

Captain Gillman had said that a Lloyds’ Committee had been formed in June 
last year. He was afraid that that committee had hidden its light under a bushel 
to some extent. He knew there existed a register of aeroplanes and he hoped 
that, if such a committee as Captain Gillman had suggested was formed, it would 
be on more comprehensive lines and should have more influence over the Air 
Ministry, i.¢., it should have the right to give judgment on any arguments between 











16 THE AERONAUTICAL JOURNAL (January, 1928 


the Air Ministry and owners or manufacturers; to-day any suggestion or proposi- 
tion could be turned down by the Air Ministry and the owners or manufacturers 
were helpless. That was why he agreed with Captain Gillman that there should 
be some form of Court of Appeal. 

With regard to grazing and the taking of land, he had economy in mind 
and was afraid that somebody would make some rude remarks that in these 
times there must be some economy and, therefore, he thought it cheaper to 
suggest grazing to ease the Ministry of some of the cost, even if it were at the 
expense of a cow or two. 

On the question of taxi-ing, he felt strongly that something should be done 
to make a hard road or, better still, to place the sheds where the machines usually 
started from so as to avoid taxi-ing altogether, because he was perfectly certain 
that it was an expensive item. 

As to his views on transport in Great Britain and Ireland, he should be very 
sorry to touch Ireland at the moment but, as far as Great Britain was concerned, 
we had first got to solve our present difficulties and really learn our business 
between London and Paris, which was an established route. When we could 
do that at a profit it did not much matter where we went, in this country or the 
other, but we had first got to satisfy everybody that the business could be run 
at a profit. If a profit could not be earned, then civil aviation was bound to die 5 
Mr. Handley Page could not expect it to be kept on by subsidies for more than 
ten years anyhow. 

With regard to Colonel Ogilvie and engine prices, he rather fancied the 
information which Colonel Ogilvie had given was wrong or he (Colonel Ogilvie) 
must be getting his engines in a very much cheaper market than he (Colonel Searle) 
could get them. 


Colonel OGILVIE said that he had not been buying, but he knew that the 
figures he had given were the right prices. 


Colonel SEARLE replied that this was not quite the moment to go into engine 
prices, but he would be pleased afterwards to do a little multiplication and division 
sum with Colonel Ogilvie in which he thought he would get a lot nearer to £6,000 
than £2,000. He agreed that perhaps it was not quite a fair way to put it in 
speaking of price per ton, but he thought that it demonstrated that much greater 
thought would have to be put into the problem of reducing engine prices. 


Major Green had said that it was utterly stupid to think that we were not 
going to improve things. Of course we were. On the question of weight, Major 


Green had suggested why not make them of cast iron. No such suggestion was 
made in the paper and it would be utterly absurd to think of it. The first thing 
was that we had got to make a good engine, but there were many ways of doing 
it. The point he wished to bring out in the paper was that, even if they had to 
sacrifice weight, they must have reliability first. It was no use saying that what 
they had got to do as designers was to make a lighter engine and a lighter 
aeroplane. The first essential was to keep the service reliable, and if the machines 


were not reliable they would all have to go out of business. When Major Green 
said these things were utter stupidity, he would like to ask him, taking the motor 
car business, what he would think of a man trving to motor from London to 
Glasgow with twenty pieces of indiarubber tubing between the petrol tank and 
the carburettor; everybody would think it very foolish, but it was these little 
things which designers must bear in mind and what he wished to impress was 
that they must have reliability even if it was at the expense of a little weight. 


Colonel Fell spoke on the matter of type tests. He was perfectly aware 
that it was a very big drain on a manufacturer to do a type test, such as was 
mentioned in the paper, but again he must come back to the question of reliability 
which they must have even if the Government paid for the type test. He felt 











January, 1922 THE AERONAUTICAL JOURNAL 17 


sure that the test to-day was not what the engine had to do in ordinary wok; 
why not make the test equal to what the engine had to do in ordinary practice? 
The job was 2 or 24 hours flying outward and 2 or 23 hours homeward and 
that had to be done every day for a month on end. When they could do that 
they had a reliable engine. That also replied to the Chairman’s remarks. 
Hitherto, we have been getting what one might call a beautiful engine, but we 
had got to get a reliable engine. They must have that in any case and he was 
perfectly willing to sacrifice some weight in order to get it. 


The CHAIRMAN, in proposing a hearty vote of thanks to the author, said that 
Colonel Searle was a very busy man, but he had taken serious trouble in this 
matter and had done very well by them in preparing such an ‘interesting, instruc- 
tive and suggestive paper, the discussion upon which had also been useful. It 
gave them the opportunity of seeing the point of view of the man who had got 
a transport business to run, and it was an opportunity which would be valued 
by those who were present. 


Mr. DERMoT MoonrEy (communicated): I do not think the lecturer is right 
in thinking that the day of the all metal aeroplane is far off, or that at best it 
will be a composite structure; nor is there any indication that the official view 
on metal construction coincides with the opinions expressed by him. 


A great deal of research and experimental work has been done on metal 
construction, with both successful and encouraging results. 


Extended flight tests of metal wings have been and are being made at home 
and abroad. 

All this is giving information which will be very valuable for constructors. 

I feel certain that if Colonel Searle knew of all the progress which has been 
made he would modify, if not entirely change, his opinions on the subject of 
metal construction. 

It is not perhaps permissible or advisable on an occasion like this to go into 
detail, but speaking generally, very considerable and satisfactory practical pro- 
gress has been made, especially with all steel construction. 

The system adopted by those engaged in working on the problem in this 
country has resulted in the evolution of a type of steel construction which already 
appears to be superior to anything produced abroad. 

Some complete all metal machines have been made in England, but most of 
the experimental construction and flight work has been concentrated on what I 
think is the most difficult part of the problem, the production of light, strong, 
efficient and durable all steel wing structure. 

I will summarise the result by stating that already steel wings have been 
and are being made, which are as light and as strong as those constructed of 
wood. 

Tests which have now extended over several years show that these wings are 
more durable, that they are less liable to destruction in case of accident, and 
that they are not subject to distortion by climatic or atmospheric variations, the 
latter an important point in machines intended for international civil aviation. 

The lecturer has, I think, rightly said that the success or failure of civil 
aviation will depend on its cost and that in effect cost is the governing factor. 
Therefore anything that reduces cost will be an aid to the progress of civil 
aviation. 

The experience of_ metal construction available is such that I have no hesita- 
tion in stating that the structure of an all steel machine will be more durable and 
require less adjustment than that of a wooden machine and consequently its 
mileage and appreciation costs will be lower. 











is THE AERONAUTICAL JOURNAL (January, 1922 


As regards capital cost. 


Given conditions which are already practical, that will not be greater than 
for wooden construction. 


Moreover, the results I have indicated can be obtained by use of steel which 
is a present day commercial product and not a laboratory one. 


Lieutenant-Colonel V. C. RicuMonp (communicated): I listened with great 
interest to Colonel Searle’s practical discourse on the requirements and difficulties 
of air transport. I hope I shall not be considered unduly critical when I say that 
I was rather misled by the title of the paper, which is practically confined to 
remarks on the Paris-London Aeroplane Service. 


Colonel Searle mentions that we must visualise as clearly as we can the 
essential characteristics of the problem. The most important of these seems to 
me to be under what circumstances can transport by aircraft provide such benefits 
te the public as to make them adopt this form of transport, even at a cost which 
is higher than that of other existing means. I cannot help feeling that the fact 
is too often lost sight of that the real benefit of air transport over a given route 
does not lie in the speed made good, nor yet in the percentage time saved, but 
in the actual net gain in time. When existing facilities can perform the journey 
in less than 12 hours, the circumstances under which it is of any value to reduce 
this time are very limited. By this I mean that if a business man can leave his 
office about the usual time of 5 p.m. and arrive at his destination before business 
commences next day, a good many of the ordinary interests of commerce are fully 
served. We can, of course, already do this between London and Paris without 
taking to the air at all, and I feel that very great credit is due to the companies 
who have already tackled the problem of air transport over this line, particularly 
because they have chosen a short route already served by sea and land transport 
developed to its maximum paving speed. 


This is contrary to transport practice, and one may point out as an illustration 
that road transport started over routes where rail facilities were bad, and it was. 
only after considerable experience had been obtained on these routes that it 
directly challenged the railways on their own main routes. 


Colonel Searle distinctly stated that if the Paris-London Service could not be 
made a paying concern the future of civil air transport was doomed. I hold an 
entirely different view and consider that we must develop long distance routes 
where there will be a net saving in time of days, and the argument that ‘‘ we must 
walk before we can run’’ does not, I think, apply in this case, because the 
commercial experience gained on the cross-channel service is not likely to be of 
much assistance in running really long distance routes, and this route is one which. 
is least calculated to be a paying concern for the reasons stated above. 


When we come to the consideration of such routes we see how many of the 
points raised in Colonel Searle’s paper show the difficulty of attempting transport 
on these routes with planes. There is the absence of the usual comforts and 
conveniences of travel, and it is doubtful if the ordinary individual could stand the 
journey to India by plane without long and frequent stops. There is further the 
need of lighthouses fairly close together, as Colonel Searle has pointed out, and 
the very small flying hours per machine per year, and the consequent low per- 
centage of capital value in use at any time will become still more serious on these 
long routes. There is further the necessity for frequent aerodromes and emer- 
gency landing grounds, also the narrow margin of available lift and the fact that 
the lift of the plane depends on its engine, which Colonel Searle points out is in 
its present state unreliable. Most of these disadvantages would be got over by 
the use of airships, and it is quite a mistaken impression to suppose that they 





a. tea ae 








January, 1922] THE AERONAUTICAL JOURNAL 19 


usurp in any way the functions of the plane. I firmly believe that a real com- 
mercial success (on a fair scale) will not be made with air transport until both 
classes of craft are used together. One of the functions of the aeroplane will be 
to act in the future as the taxi to the airship, i.e., if one chief landing centre for 
airships is provided in each country or colony, the aeroplane will avoid any loss 
of time by taking the passenger from that landing centre to whatever part of the 
colony he wishes to reach. 


General Sir W. S. BraxckER (communicated): I regret that my absence in 
Paris for the Air Congress prevented my attendance at Colonel Searle’s lecture 
on ‘* Aerial Transport,’’ but I venture to ask for the publication of the following 
remarks :—First, out of loyalty to my old organisation, Aircraft Transport and 
Travel, as well as for the sake of aerial transport, I must criticise some of his 
statements. 


I agree with every word he says, but I don’t agree with the way he says it. 
Every precept and principle which he lays down was realised and accepted before 
he had even appeared on the stage of aerial transport. He criticises the employ- 
ment of a large number of unsuitable machines; but if they had not been used 
nothing could have been done at all; and it was the constant effort to make im- 
provements which led to a multiplicity of types and consequent large numbers. 
Actually the first really economical machine in the world was produced and was 
lying for the company before Colonel Searle arrived, and it was only after his 
arrival that a programme involving the construction of eight similar standard 
machines was abandoned, and operations continued with the old types, which 
everyone knew ought to have been scrapped. He says that someone—who must 
be either General Festing or mvself—stated that an aeroplane could only fly 250 
hours in the vear. This is not so; I always said that the number of hours that a 
machine could fly depended entirely on the efficiency of the administration and 
on the efficacy of the weather-combating organisation, but that, until we had 
obtained real experience as to what could be counted on, I would make my esti- 
mates of costs and plans on the basis that a machine could fly 250 hours, whatever 
happened, and that, therefore, we should always be on the right side in our 
calculations. He talks as if no calculations had been made; actually, the whole 
of the costs had been most carefully worked out and the estimates have been 
pretty well borne out by subsequent operations. 





Colonel Searle does not touch on two important points on which I should 
have liked to hear his views; the numbers of hours pilots should be called on to 
fly; and the type of machine which is required for the real reliability of service 
for which he is striving. I feel strongly that there is a tendency in some direc- 
tions to over-work pilots for the sake of saving money ; this is utterly false economy 
and will only lead to unreliability and unnecessary danger. In present conditions 
I feel that no pilot should be called upon to fly more than five hours in one day, 
or sixty hours on the average, a month, in a regular service where flying by night 
and in all weathers is imperative. In addition, he must be given leave at the rate 
of about ten days every three months. Regarding the type of machine employed, 
I am convinced that stability is a factor of utmost importance, and I feel that 
we are rather losing sight of this fact and concentrating almost exclusively on 
useful load and durability. 

Finally, Colonel Searle’s lecture makes me a little apprehensive lest a business 
and transport expert, without real knowledge of aviation, may not do aerial 
transport more harm than the common-sense man who understands aviation but 
has no business training. 


Mr. G. Hott THomas (communicated): I regret that the date of Colonel 
Searle’s lecture clashing with the International Congress in Paris, I was unable to 
be present. I am, however, writing a short comment on his lecture as, perhaps 
unintentionally, he retlects somewhat on my managers at the start of the London- 











20 THE AERONAUTICAL JOURNAL January, 1982 


Paris Air Express. As a matter of fact I agree generally with Colonel Searle in 
so far as running an aeroplane service for profit is concerned, but he forgets that 
the first thing to do was to find out, with the means at our disposal, whether an 
aeroplane service were possible. Nobody knew at the time the air express was 
started whether it was possible to fly between London and Paris daily to scheduled 
time, with sufficient efficiency to be commercial. I am popularly supposed to 
have as much experience of flying as perhaps anyone in the world, but I can 
frankly say, with the climate we have between these two capitals, that I could 
not answer this question without a test. Colonel Searle says, ** It is perhaps easy 
to be wise after the event ’’; but so far as I am concerned, I was no wiser, and, 
looking back, I can say quite frankly that I would do the same thing again. I 
should never have attempted to design rolling stock for any transport until I knew 
whether such a service were possible, and to find this out I took the war machines 


existing and the finest pilots I could find. The efficiency of the service was an 
eye-opener to the world, and was due to the loyalty of the pilots. They were 


determined to get through whenever possible, and if I were to select men again 
to do the same thing, I should, generally speaking, select the same. 

After it was proved that a service between London and Paris was possible, 
I do not think that any management could have been quicker to appreciate it than 
my own. The service was started on the 25th August, 1919, and, as far as my 
memory carries me, I should think that by October 25th Captain de Havilland 
was on to a really commercial design, suitable for the purpose, resulting in the 
).H.18, one of which was delivered when Colonel Searle took charge, and I 
regret to say that his directors were responsible for stopping the delivery of the 
rest of the batch, ready for the spring of 1920. At this time also the commer- 
cialising of aerial transport was a perfectly natural sequence. On looking back, 
even to-day, with the much greater knowledge at our disposition, I can only see 
that the three definite steps taken were absolutely necessary, viz., firstly, the 
trial of a service with the machines available and the best pilots obtainable ; 
secondly, when proved possible, the design of suitable rolling stock; and thirdly, 
bringing the service down to a purely commercial problem; but I think my 
management would have been very much at fault if they had in any way reversed 
these processes; and the fact that Colonel Searle had not the proper machines 
for the service to deal with shortly after he took charge was, as I have said above, 
not the fault of the pioneers of this service, but the fault of his own directors who 
stopped the delivery. This was the more regrettable as the machines, even if 
the service had been stopped as it was proposed to be stopped, would have been 
saleable, with a great many replicas, to many other nations, and the founders of 
the first British service would also have had the very remunerative task of running 
other services in many parts of the world. 

I am so much in agreement with Colonel Searle's general statements that 
{ hardly like to comment on his lecture, but at the same time I cannot let his 
observations on the foundation of the service pass without comment, as the steps 
necessary to its establishment were so obvious and, indeed, the service could not 
have been arrived at in any other way. 


REPLY TO WRITTEN CRITICISMS. 


Mr. Mooney.—Mr. Mooney is apparently an enthusiast in the all-metal 
aeroplane and his comments really amount to a statement that the all-metal aero- 
plane is nearer a commercial proposition than I understand. The research and 
experimental work in this direction, which he states has been done, if from lack 
of publicity, one is to interpret secrecy, then the results must have been either 
very successful or the reverse. In any case, Mr. Mooney’s statements are all 
abstract and he gives no facts. As we have no information yet available as to 








aseaaa 





January, 1922] THE AERONAUTICAL JOURNAL 21 


the life of the ordinary wood and fabric aeroplane, it is difficult to make compari- 
son with the all-metal machine other than that, as we all think, metal will with- 
stand the weather perhaps better than wood. As far as capital cost is concerned, 
Mr. Mooney qualifies his remark by conditions, the practicability of which is only 
based on Mr. Mooney’s abstract statement. 


Colonel Richmond.—Colonel Richmond is quite correct in saying that my 
paper is practically confined to remarks on the London-Paris aeroplane service. 
Where else has commercial aviation been attempted on anything like such a 
scale? This route would naturally be referred to as a basis because it is the only 
one on which any serious development is taking place and on which the eyes of 
the air transport world, so to speak, as well as the public, are fixed. Colonel 
Richmond dismisses in a few words the discomforts of a night journey to Paris 
and, in fact, he converts the most uncomfortable civilised night journey which | 
know into almost a pleasure trip for the business man. Furthermore, I abide by 
my statement that if the London-Paris Air Service cannot be made a paying con- 
cern the future of civil air transport is doomed, but in making this statement, | 
am referring naturally to aeroplanes alone. The London-Paris route has all the 
best ground equipment and organisation lavished upon it; it has a constant heavy 
passenger and goods traffic available and it affords a unique example of superiority 
of air travel by reason of the interposition of the English Channel. It is, there- 
fore, of the utmost importance to air transport that the London-Paris service be 
made a commercial success. As far as airships are concerned, and in which 
Colonel Richmond appears particularly interested, I am convinced that the airship, 
as a transport vehicle, is capable of paying its way, but there seem to be very many 
technical difficulties in the way at present. The two in particular which remain 
outstanding in my mind are, firstly, that of the deteriorating effect of sea air 
upon a duralumin structure and the difficulty of keeping a preventative coating 
upon such a_ structure which is constantly working at almost every joint. 
Secondly, there seems to be a great difficulty in preventing gas leakage and in 
handling the gas in varying altitudes. I am entirely in agreement with Colonel 
Richmond on the importance of the airship for developing Dominion and Colonial 
communications and, to my mind, it would be a great pity if we scrapped some 
45 millions which have been spent on airships for the sake of spending another 
quarter of a million to determine definitely their value. 


General Brancker.—I can only repeat what I said in my paper that I was 
told by a high authority on flying that an aeroplane could only fly 250 hours a 
year, and I will now add that it was generally taken for granted in the air world 
that 250 hours a year was about as much as a machine could do. I am entirely 
in agreement with General Brancker on the number of hours which pilots can be 
called upon to fly, although for summer work I think that 60 hours a month is on 
the small side if it is not going to be reached in the winter; air traffic is somewhat 
similar to omnibus traffic in that it increases considerably in the fine weather, 
so that I think the summer average for pilots will probably be as much as 80 hours 
per month and in the winter as low as 4o. I am also in agreement with General 
Brancker’s view that pilots should have ten days or a fortnight’s leave at definite 
periods. 


General Brancker is quite correct in stating that I was responsible for can- 
celling the construction of the eight D.H.18’s to which he refers. This cancella- 
tion cannot be interpreted as a disapproval of the mere ordering of those machines, 
but as General Brancker has entered into details so far it is necessary to complete 
and to say that at the time these machines were being built there was already 
something like £60,000 worth of aircraft on the books of the Air Transport and 
Travel Co. The financial responsibility of bringing eight more machines, or about 
another £/50,000 on to the books of the company, as a debt to the parent company, 
will be obvious to a business man when the following facts are considered. 











22 THE AERONAUTICAL JOURNAL (January, 1922 


The original 460,000 of aircraft were capable of carrying something like 
120 passengers a day at one trip per day each machine; the new eight machines 
provided a further capacity for 144 passengers a day on the same basis; at this 
time the number of passengers being carried on aircraft generally amounted to 
about 30 a day, and as there were vacant seats it is to be assumed that that is 
the number available. General Brancker suggests scrapping the £60,000 worth 
of aircraft, but the action of scrapping the material and the cleansing of the 
balance sheet after such an operation are two very different things which General 
Brancker does not appear to have considered. 

With reference to General Brancker’s apprehension in the last paragraph of 
his letter, my own feeling is that a commercial engineer and transport expert 
should gain the equivalent knowledge of what is termed ‘‘ aviation ’’ to the air 
expert in very much less time than the average air enthusiasts could learn the 
principles of business. 


Mr. Holt Thomas.—Mr. Holt Thomas’s letter of comment is so logically put 
together that in reading it one is likely to be carried out of sight of the main facts 
at issue. He also, however, refers to the cancellation of the D.H.18 order to 
which I have already replied to General Brancker. 


With reference to the main point which figures throughout Mr. Holt Thomas’s-. 
letter, viz., that of the establishment as fact as to whether an aeroplane service 
was possible, surely this could have been determined with two D.H.4’s or 16’s 
instead of a collection of about 25 machines, most of which varied one from the 
other, and a young Air Ministry to run them. 











January, 1922] THE AERONAUTICAL JOURNAL 23 


PROCEEDINGS. 
FOURTH MEETING, 57th SESSION. 


A meeting of the Royal Aeronautical Society was held at the Royal Society 
of Arts on Thursday, December 1st, the Chairman, Liecut.-Colonel O’Gorman, in 
the chair. 

The CHAIRMAN, in opening the meeting, said it would be a pleasure to 
hear Major Scott, because he had given such exceptional proof of his faith in 
his subject—airships. He was one of the few now alive who had flown over the 
Atlantic, and as they knew, Major Scott was in charge of the airship which crossed 
to America. Major Scott had asked him to mention that although the printed title 
of the paper was ‘‘ The Present State of Airship Development,’’ that was an 
error. As printed, the title rather suggested a political significance, in view of 
the fact that no one quite knew to-day how England stood with regard to airships 
at the present time. The paper dealt with the technical position, and the title 
should really be ‘‘ The Present Technical Position of Airships.’’ 





THE PRESENT STATE OF AIRSHIP 
DEVELOPMENT. 


Introduction. 


At the time when the question of the development of civil aviation is so much 
in the public mind, I am most grateful to the Royal Aeronautical Society for giving 
me this opportunity of summarising the technical position of the airship to-day. 

It seems to me that if air transport is to take its place with other existing 
forms of transport the long distance routes of the world must be established, 
and my object in summarising the present technical position of the airship is to 
enable you to form an opinion as to whether the modern airship is capable of 
taking its place in establishing these routes. 

I have confined my remarks to the rigid as it is the large airship which is 
the most suitable for this long distance work. 

As this long distance work has a distinct bearing, in my opinion, on the value 
of the airship for naval purposes, I have made a brief reference to this aspect of 
the subject. 

In considering the present state of technical development it is possible to deal 
with each of the individual parts separately, and this I propose to do under the 
following headings :— 


(1) Hull. 

(2) Fabric. 

(3) Engines. 

(4) Safety. 

(5) Handling on the ground. 
(6) Handling in the air. 

(7) Navigation and wireless. 


Hull. 


The hull of an airship is constructed of a number of rings or transverse 
frames, these rings being composed of straight duralumin girders forming the 
circumference, and prevented from radial distortion by wires connecting the ends 
of each straight girder to the centre. These wires are known as radial wires. 











24 THE AERONAUTICAL JOURNAL (January, 1922 


These transverse frames are spaced axially along the ship and connected by 
straight girders known as the longitudinal girders, this whole framework being 
stiffened by diagonal wires between adjacent longitudinals. 

At the bow and stern these transverse frames are reduced in diameter, thus 
giving the required shape. , 

In early rigid airships a strong external triangular keel was attached to the 
hull, but built separately from it. 

This keel carried all the loads, the petrol and water ballast being slung inside 
the keel, and all cars or gondolas underneath this keel and transmitting the 
propeller thrust to the keel, and in the very early airships the rudders and elevators 
were also built on to this keel. 

The lift of the gas was taken by nets, which transmitted it to the main trans- 
verse frames. From each joint in this main transverse frame, lift wires were 
carried down to the keel. 

Owing to the slow speed of these early ships, and their small size and there- 
fore concentrated loads, the dynamic forces on the ship were light, whilst the 
static forces were heavy. 

This external keel was constructed strong enough to take all these loads, the 
hull being little more than a framework to take the gasbags, and transmit their 
lift down to the keel, the keel dealing with all bending moments and shear forces. 

This principle of an external and separate keel was followed out in the naval 
airship No. 1, and in R.g and the R.23 class. 

With increase in size and consequent increase in speed a better streamline 
form became necessary, the streamlined form being first introduced by the Schutte 
Lanz Co., in 1909, although not copied by the Zeppelin Company until many 
years later. 

The ratio length to diameter for this first streamlined ship was 7.1 to 1 as com- 
sared with 9 to 1 for the contemporary Zeppelins. 

The reduction in finesse ratio reached its limit in the German commercial 
airship Bodensee, with a ratio of 6.5 to 1; this ship had a speed of 81.2 m.p.h. 

The increase in speed resulted in an increase in dynamic forces; it therefore 
became necessary to increase the strength of the hull structure, and deeper girders 
were introduced. 

The hull was now capable of taking some of the shear and bending loads, 
and owing to the difficulty of estimating proportions of load taken by keel and 
by hull structure, when separate, the keel was built inside the hull and as part of 
the hull, the keel, however, still acting as the load carrier between the niain trans- 
verse frames. 

This introduction of an internal keel reduced the over-all height of the airship 
and allowed a larger diameter ship to be built in the existing sheds. 

With the introduction of the larger diameter it was found that the stresses 
in the radial wires became excessive from the end pressure of the gasbags when 
the ship was pitched at a steep angle, or the gasbags were not all at the same 
degree of fulness. 

To release this tension in radial wires, an axial wire was introduced. This 
wire runs longitudinally through the centre of the ship, passing through the 
gasbags, and connected to the centre pad where the radial wires meet. 

Shear wires were also introduced; they lead from the top of one main trans- 
verse frame through the gasbag to the keel at the foot of the adjacent frame. 

They were only fitted in sections where the loading was heavy and therefore 
shear forces big. 


The increased number of engines now carried by airships necessitated the intro- 














January, 1922 THE AERONAUTICAL JOURNAL 25 


duction of wing power cars in order to allow a clear run for propeller slipstream 
and prevent interference. 

In the very early ships, fins, rudders and elevators of the box type were 
employed, but these were superseded in 1912 by the simple fin, but with increased 
speed the head resistance of this type of fin became excessive owing to the large 
amount of external wiring required to support it, and in 1918 streamlined or 
cantilever fins were introduced. 

This brings the British airship up to the R.36 class, which can be taken as a 
thoroughly proved design, embodying no experimental features. 


Her dimensions are :— 


Length ... Zs ae Ae 672.2. feet. 

Diameter ... a. oe eh 78.75 feet. 
Capacity .. as sar a 2,101,000 cubic feet. 
Gross lift Ae je sia 63.8 tons. 

Useful lift — see sh 23.5 tons. 

Horse power... se me 155 70- 

Full speed aie $f ee 56 knots. 

Cruising speed ... he seg 45 knots. 


Germany has proved one step ahead of this country by the introduction 
of 15-metre gasbags, /.¢., main transverse frames are spaced 15 metres apart 
instead of 10 metres as in British and previous German airships. 

These 15-metre gasbags were employed in all ships of the L.6o0 class and in 
the L.71 and L.72 and proved satisfactory. 

It was found after trials that the greater distance apart of the main trans- 
verse frames caused vibration of the keel or corridor, and stirrup wires were 
introduced. These wires lead from the top of the main transverse frames through 
the gasbags on to the corridor, midway between main transverse frames, sup- 
porting the corridor at this point; they also, to a certain degree, take the place 
of shear wires. 

The next step taken by this country was the construction of R.38. 

R.38 embodied the 15-metre gasbags, but omitted stirrup wires. Other new 
features introduced’ were :— 

Increased diameter from 8oft. to 85.6ft. 

Modified form of corridor, the old triangular form being superseded by a 
four-sided section. 

New method of gasbag wiring, the nets and diamond form of gasbag wiring 
being replaced by circumferential wires, running parallel about gin. apart right 
round the ship. The lift of the gas is taken by these wires and is transmitted 
from them to the main transverse frames by catenary wire, a new feature of this 
design. 

Larger petrol tanks were introduced in order to concentrate the loads at the 
main frames. 

Previous tanks were of 80 gallons capacity and the new R.38 tanks were of 
160 gallons capacity. 

A modified form of balanced rudder and elevator were also introduced. 

As stated in the report of the Court of Inquiry, R.38 was wrecked due to 
structural failure in the air. 

A careful investigation into the causes of this failure is at present being 
undertaken by the Accidents Investigation Sub-Committee of the Aeronautical 
’ 7-CT ae y > : 

Research Committee. I am not at liberty to make any statement at present. 


Some of the features introduced into R.38 are no doubt sound and it must 











26 THE AERONAUTICAL JOURNAL (January, 1922 


be realised that R.38 was designed for a very special performance, and the trials 
indicated that this performance would have been realised. 


Summarising, there is in existence to-day an airship of the R.36 type, proved 
and tried out, with a performance as stated earlier. 


Also it would be possible to build an airship of 2,500,000 cubic ft. capacity 
without embodying any new features that have not already been tried out and 
proved in this country or in Germany. 


Fabric. 

The hydrogen to which the buoyancy of the airship is due is contained in 
bags which must be as light, gastight and flexible as possible. The material 
which was first employed by the Germans was cotton proofed with rubber. The 
Germans were not long in deciding that this was unsatisfactory ; even with such 
a relatively high weight of rubber as 150 gramms. sq. metre, a very good per- 
meability could not be obtained. (At the best about 6 to 7 litres/sq. metre per 
24 hours.) At this time the subject had not been sufficiently studied for a really 
durable type of coating to have been produced. The Germans lost one or two 
ships by fire, notably the ** Schawben,’’ and they attributed the fire to static 


electrical discharge. This discharge they imagined arose from the friction of the 
rubber on the hull of the ship. They then turned their attention to the use of 
goldbeater’s skin. This substance, which forms part of the intestines of the ox, 


is remarkably light and strong. In addition, it has a lower permeability for its 
weight than almost any other known substance. One layer of the skin is far too 
fragile to be used by itself, and in the early davs bags were made of as many as 
seven to ten layers. This was very costly and involved an’ enormous amount of 
labour, as each skin is not much more than 1ft. square. A definite advance was 
then made by employing goldbeater’s skin in conjunction with cotton, the cotton 
giving the necessary strength and the goldbeater’s skin the necessary gastight- 
ness. Under these circumstances, two lavers of gcldbeater’s skins are sufficient, 
which with the weight of the adhesive emploved need not be more than 


60 gramms./sq. metre. The permeability of this composite fabric rarely exceeds 
nore than 1 litre/sq. metre ’24 hours, if carefully made. This vou will see con- 


stituted a very distinct advance over the original rubber proofing referred to above. 
The medium employed to attach the skins to the fabric is a matter of some 


considerable importance. The Germans have emploved a gelatine glue, whilst a 
rubber solution has been used in this country. Also the actual method of laying 


the skins was different in the German case to that emploved here. In the course 
of extensive experiments which have been carried out in Egypt this year, it has 
ranspired that the thin film of rubber emploved for adhesion suffers badly under 
tropical conditions, and is in all respects an unsuitable substance to employ on 
airships which will have to do much flying under tropical or semi-tropical condi- 
tions. Samples stuck with gelatine glue have not suffered in this way, and hence 
there is no doubt that we can make gasbags in this country on the German princi- 
ple which will be durable under the conditions referred to above. The glue 
adhesive used is fortunately a fair conductor of electricity, and therefore the 
original German objection to employing an insulating material, such as rubber, 
is done away with. So that to-dav it is possible to build gasbags capable of 
withstanding all weather conditions met with in this country, and giving a life of 
at least two vears, and from the result of sample tests we can say these bags will 
also be capable of withstanding tropical conditions. The objections to the use of 


goldbeater’s skin are, of course, the enormous number of skins required (over 
300,000 in the case of a ship such as R.36), and the immense amount of labour in 
laying these skins, both of which causes make the gasbags very expensive. A 
good deal of work has been done on synthetic substitutes for goldbeater’s skins, 
which is very, promising. 


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January, 1922] THE AERONAUTICAL JOURNAL 


Engines. 

The requirements for an airship engine are essentially different from those of 
an aeroplane engine, and are not met by the latter, yet no British airship engine 
has yet been developed, the only engine designed to meet airship requirements 
being the German Maybach. 

In the past airships in this country have been obliged to use engines designed 
for aeroplanes, and even of such engines it has not been possible to select the most 
suitable. 

The average requirement of an aeroplane engine is a few minutes at full 
power followed by some five to six hours at about three-quarters power. 

The airship requirements are considerably more exacting; for commercial 
airships the average flight will be about 50 hours, and the engine will be required 
to develop three-quarters full power with occasional stops for the full period, or 
to develop full power for three-quarters of this period. 

The aeroplane engines employed in the past could not be relied upon to stand 
up to either of these conditions, which is reasonable in view of the very different 
conditions for which they were designed. 

The modern airship starts its journey with about 2olbs. of fuel for every 
rated horse-power of the engines, while the corresponding figure for aeroplanes 
does not often exceed five. 

This indicates the relative importance of fuel economy and engine weight in 
the two cases, thus a 10 per cent. increase in fuel economy under working condi- 
tions is equivalent to about 2lbs. weight per h.p. in the engine. 

An engine designed for airship work may therefore have a higher weight per 
h.p. provided there is a corresponding decrease in consumption, and such an engine 
running at lower revolutions would be more reliable and have a longer life. 


Hydrogen as Fuel. 

The idea of burning hydrogen in the engine as a means of economising fuel 
and thus increasing the performance of the airship has been under consideration 
for some time, but until recently no satisfactory method of burning hydrogen alone 
or hydrogen and petrol mixed, had been devised; recent experiments, however, 
have indicated a method of using the two fuels mixed, and this should very greatly 
increase the performances of the airship in the future. 

The use of kerosene or crude oil to replace petrol in both aeroplanes and 
airships would substantially decrease the danger of fire, as although the danger 
of fire in airships is small, what danger there is, is almost entirely due to the 
presence of petrol. The development of the use of kerosene or crude oil is ob- 
viously important for commercial airships, and can be confidently predicted once 
this demand is realised. 


Propellers. 

In the early airships the propellers of an airship were carried on brackets 
attached to the hull and driven by gearing and shafting from the engine car. 

This method was superseded in 1916, and all propellers placed at the after 
end of their respective power units and driven through reduction gear. 

A later development in German airships and now copied in British airships 
was to put a direct drive between the engine and the propeller, a very small com- 
pact power car being employed. 

_ The efhiciency of the gear-driven propeller is higher than that of the direct 
driven propeller, but this is to a certain extent nullified by the large power car 
required and the longer struts and suspensions necessary owing to the larger 
diameter propeller, thus increasing the head resistance of the power unit. 





23 THE AERONAUTICAL JOURNAL (January, 1922 


The increased reliability of direct driven propellers is a big factor in their 
favour. 

g, there is no airship engine in existence in England to-day but 

the requirements are such that there should be no difficulty in constructing a 


Summarising: 


suitable engine. 


Taking the German Maybach as an example, all present requirements are 


met. 
Future development in airship engines should work toward the use of heavy 
oil and reduction in consumption. The value of reduced consumption to the 


airship is not generally realised. 


Safety. 

I think it is not generally realised that on the occasions when modern airships 
of proved type have been wrecked it has invariably been due to accidents 
happening whilst handling on the ground, this of course excluding losses due 
to enemy action. 

The question of the safety or danger of a modern airship may be considered 
under two headings: (1) dangers due to fire, and (2) dangers due to weather 
conditions. 

The dangers due to fire may be again sub-divided into those due to petrol 
fuel and those due to hydrogen. 

Firstly, as regards petrol, contrary to popular opinion the danger of this 
source is considerably more serious than that due to hydrogen. Although this 
danger is certainly no more serious than that due to the same cause in an 
aeroplane, it is obvious that every effort should be made to eliminate it. This 
should be possible in the near future by the use of high-tlash-point fuels already 
referred to, mechanical refinements of the fuel installation, and the abolition of 
any contributory causes of fire such as sparks from clectric leads. 

As regards hydrogen, in all cases of fire in rigid airships, the ignition of 
the hydrogen has been a secondary cause. These cases are few except for enemy 
action. In such operations where the present type of airship can be reached by 
heavier-than-air craft with incendiary ammunition, there is no doubt it is very 
vulnerable and its naval use accordingly limited. It must be remembered, however, 
that owing to its superior range there are many areas of operation where the 
heavier-than-air craft could not engage. 

The question of the protection of the airship against incendiary attack has 
not been fully worked out, although experiments with the use of helium, and in 
the use of an outer envelope of non-inflammable gas, have given very promising 
results. 

The successful development along these lines would entirely remove the 
disadvantages of the present airship’s vulnerability when operating where heavier- 
than-air craft can attack. 

Weather Conditions.—I have already pointed out that a hull of 25 million 
cubic feet could be built to-day with the same factor of safety as R33 and R34, 
which ships have safely weathered the worst conditions in the air. The dangers 
that might be met in the air are: 

(a) Electrical Disturbances.—The chief danger in an electrical disturbance is 
not as is generally thought due to lightning, but to the very violent air currents 
that might bring excessive strains on the hull structure. It is, however, even 


with the present meteorological organisation, which is not specially arranged to 
meet airship requirements, and with present air knowledge, comparatively easy to 
avoid thunderstorms. I can definitely say that thunderstorms in this country do 
not constitute a danger to airships, neither will they constitute a danger in the 





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January, 1922 THE AERONAUTICAL JOURNAL 


bo 
Se) 


tropics, for the reason mentioned above, as with the development of airship 
routes the meteorological organisation will be extended to meet our compara- 
tively simple requirements. 

(b) Snow.—The danger from snow is the possibility of the airship becoming 
so heavily coated that she will be driven to the ground. “Experience in the air 
and from maintaining a ship at the mooring mast, points to the fact that little 
danger exists from dry snow, as this snow blows off and does not collect on the 
ship. Damp snow and slect are the chief dangers. When flying through snow 
and sleet, however, at the first sign of snow collecting the ship can rise into the 
dry snow, 1,000ft., in most cases, being sufficient. 


Handling of Airships on the Ground. 


The handling of the airship on the ground has until recently been the 
limiting factor in the usefulness of the airship. 

Thus an airship operating from a shed was handicapped by the fact that 
except in moderate winds the airship could not leave the shed, and an airship 
arriving back at a base was obliged to wait for a suitable opportunity to enter 
the shed. This often resulted in an airship being recalled at the first sign of bad 
weather, as although there was no difficulty of the airship flying through the 
bad weather, it was essential to house the ship before the wind became too 
strong. 

Recent experiments with a mooring mast have demonstrated the fact that an 
airship can moor out in bad weather, and also that an airship can land or leave 
in weather in which it would be absolutely impossible to handle her out and into 
a shed. 

To summarise the results of these experiments. 

It was proved that an airship could remain at a mooring mast, comfortably, 
in winds up to 60 m.p.h., riding through hail and snow squalls. 

It was demonstrated that a ship could, with ease, leave a mast in a 4o m.p.h. 
wind. 

It was demonstrated that a ship could land at a mast in winds up to 
32 m.p.h. 

It was shown that necessary running repairs could be undertaken on a ship at 
the mast with safety. 

It was shown that the hull deterioration, at a mast, is not heavy, the outer 
cover and gasbags were not so satisfactory ; but as a result of sample tests carried 
out in Egypt, I think we can confidently say that the cure for this trouble is well 
in sight. 

I will now discuss the advantages to be obtained from the use of a mooring 
mast. 

From the service point of view there are two very big advantages. 

During the war it was often found that when a large airship was particularly 
required, it was unable to leave its shed owing to the difficulty of handling in a 
wind. With a mooring mast at least one large ship would be maintained at the 
mast, and could slip in anv weather at very short notice, thus taking the place 
of the fast light cruiser. Also in the event of naval or military operations in 
any part of the world where no shed base was available, mooring masts could be 
quickly and cheaply erected, thus allowing airships to operate. 

The commercial value of the mooring mast is even greater. An airship 
working from a mast can be relied upon to leave regularly at scheduled time, and 
provided the weather is not too bad to fly, which is a very rare occurrence, it 
can land without danger, thus making a regular airship service possible. 

Another point of equal importance is the great reduction in personnel. Instead 
of requiring a Jarge Janding party of three hundred to four hundred men to handle 
a ship whenever she lands, a mast crew of only 1o men is all that is required, 
and only in the event of docking a ship at one of the main shed bases is a large 








30 THE AERONAUTICAL JOURNAL [January, 1922 


party required, and then not so large as hitherto, as the airship would only be 
housed under good weather conditions. 

In considering an airship route, another point of great importance is the 
reduced number of sheds necessary, as instead of having sheds at each landing 
ground, they would only be necessary at the terminal or special junction stations. 
This will mean a very great reduction in capital expenditure on any airship route. 


Handling the Airships in the Air. 

I will now discuss a few points relating to general airship flying. 

In most modern airships the engine cars are arranged so as to have one 
power car on the centre line right aft. This practice has, however, in some 
ships been modified, notably in R80 and the R38, in these ships a pair of power 
units being placed aft. 

There is little doubt that the earlier practice is better, giving better control 
at low speeds owing to the slip stream of the propeller acting on the rudder, in 
the R33 class it being possible to swing the ship about on her rudder, without 
losing or gaining ground, by running ahead on the after car and astern on the 
two wing units. 

A single car alt is also of great value when handling on the ground, as 
it forms a foot on which the airship can rest, and a handrail to which the 
landing party can hold. 

The effect of size on performance is of fundamental importance and has a 
marked bearing on all future development. 

The lift of an airship varies as its (linear dimensions)*, being proportional to 
the total volume of the gas contained in the gasbags. 

This should be clearly distinguished from the lift of an aeroplane, which is 
proportional to the area of the wing surface and therefore varies as the (linear 
dimensions)? while with airships the lift varies as the (linear dimensions)". 

The head resistance, and consequently the B.H.P. necessary to drive the 
airship through the air, is proportional to the (linear dimensions)*, consequently 
with increase in size the airship can increase its speed, or if the speed remains 

. disposable lift . ake 
constant the ratio ————— increases, and the ship’s range or percentage 
gross lift 
weight-carrying capacity increases as the linear dimensions 3) 2. 

Also allowing a constant percentage of the gross lift tor fuel, the range 
varies in the same ratio, that is, increases with size of ship. 

A very important factor to be dealt with by the pilot in flight is the super- 
heating of the gas, either by the effect of sun radiation or sudden alteration of 
air temperature. The latter is generally met with on alteration of height. 

The effect of this superheat ts to alter the lift of the airship, and this makes 
her suddenly light or heavy while flying. 

The airship then has to be flown at an angle to her flight track in order to 
produce a balancing dynamic force. 

In cases where this superheating is big the loss in speed due to the angle at 
which the ship is flying can be considerable. It is, therefore, necessary to reduce 
this degree of superheating in an airship. It is for this reason the outer covers 
of airships are doped with aluminium, to reflect the sun’s rays. 

In earlier ships, and even in the case of the original cover fitted to R34, the 
covers were poor and afforded little protection. Recent covers, however, doped 
with Farnborough dope, have shown a very great improvement, and will probably 
be fairly satisfactory even in tropical climates. 

Another method of reducing superheating is by ventilating the air space 
between the gasbags and the outer cover. This is done to a small extent in all 
airships by the gas cowls, but it is a point requiring further consideration, and 


one that should present few difficulties. 











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January, 1922] THE AERONAUTICAL JOURNAL 31 


Navigation. 

Navigating instruments employed in airships are similar to instruments used 
by sea craft, with the addition of the R.A.E. sextant. 

This instrument is now suthciently well known not to require a detail descrip- 
tion; it fulfils all airship requirements, and under good conditions gives a position 
line with an error of between 5 and to miles, which is accurate enough for airship 
purposes. 

Compasses are of standard type and can be easily corrected to within 
reasonable limits. 

The general degree of accuracy that can be obtained in airship navigation 
is such that under most conditions the true position can be estimated to within 
30 miles. 


Wireless. 

The wireless for airships is now in a position to meet all modern require- 
ments, a suthcient range being obtained to ensure an airship being at any time 
in communication with a wireless base even in mid-Atlantic. 


Conclusion. 


In conclusion, I would like to summarise the technical position of the airship 
to-day from the details 1 have already given. 

An airship of 2,500,0co cubic feet (75 tons) can be built without introducing 
any experimental and untried features. The hull would last, in continuous service, 
for at least five vears, and would have a useful lift for freight of 12 tons 
(passengers 5 tons, mail, etc., 7 tons) for non-stop journeys of 2,400 miles, i.e., 
England to Egypt. A journey of this distance (England-Egypt—2,40o0 miles) 
could be completed in 48 hours or at a speed made good of 50 m.p.h. 

The ship would be of a rugged construction, built for long life and low main- 
tenance cost, and with a factor of safety at least equal to the R.33 and R.34, 
which ships, as you know, have shown themselves capable of standing up to the 
worst weather conditions, both in flight and at the mooring mast. 

The ship could be operated to meet commercial requirements, that is to say, 
arrivals to and departures from a mooring mast could be made to scheduled times 
and regularity on passage equal to that of steamships would be possible. 


In regard to future developments, those actually in sight not only considerably 
improve the performance I have taken above, but also materially reduce the present 
cost of manutacture and operation. 

Finally, I would like to emphasise three further points which appear to me 
most important :— 

(1) An investigation into the present commercial requirements on 
Imperial routes indicates that some 5 or 6 tons of mail and freight 
and 30-40 passengers would be available weekly. 

(2) The performance of the commercial airship which could be built 
to-day, and which I have given, would meet these requirements. 

(3) The urgent need for speeding up Imperial communications is 
acknowledged by everyone throughout the Empire and an examina- 
tion of the possible means by which this demand could be adequately 
met, with due regard to cost, points in my opinion to the use of the 
airship. 

\s a point of interest, | would like to mention that from recent publications 
in Germany, it is quite clear that a considerably more optimistic view is taken 
in that country both as regards the present technical position of the airship and 
its future possibilities than that which I have given in this paper. 


o 
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THE AERONAUTICAL JOURNAL (January, 1922 





DISCUSSION. 


The CHairMAN, in declaring the paper open for discussion, expressed the 
hope that even those members of the Society whose interests were mainly centred 
in aeroplane construction would not refrain from entering into the discussion 
through any false modesty as to their lack of knowledge of airship matters. 
Aeronautics was a very big subject, and he hoped there would be some representa- 
tive remarks from aeroplane makers in the discussion. He called upon Mr. 
Burgess, of the United States .\ir Service, who, he said, was thoroughly well 
versed in airship design, to open the discussion. He added that he only regretted 
that Mr. Burgess was quite unwarned that he was to be called upon. 


Mr. BurGrEss said that in America they had been trying to develop the 
rigid airship. The first one was based mainly on the German L4g9, which was 
brought down about four vears ago, and they had proceeded on the assumption 
that they should wring German experience dry before proceeding to anything new. 
There was, however, one point they should consider in going ahead 
with airship development, as the author had suggested, and that was 
that the Germans were designing for high altitude, whereas in com- 
mercial development, and probably even in naval development in the future, 
we should want long distance rather than high altitude, and although load 
and altitude were in a sense convertible terms, the strength required, 
and the reliability of the engines, and even the type of engines, were really quite 


different. Therefore we must keep two points in mind—firstly, to go by experi- 
ence. We must not forget experience, because any a priori attempts in airship 
design would most certainly involve us in serious trouble. Secondly, it was 


necessary to get all the theory we could, because we must advance, and simply 
to go step by step in peace time would be so slow that there would be little 


chance of making reasonable progress in the next ten vears. Therefore we must 
get all the experience and all the science we could together. He was afraid that 


possibly in the past there had been a certain antagonism between the theoretical 
man and the practical man, which had prevented us from making all the progress 
we ought to have done, and it was to be hoped now that having learned our 


lesson, the theoretical man and the practical man would combine forces. Another 
thing was that airships were now in a very precarious state, and that made it 
all the more necessary for us to pull together. I! possible, we should get our 


late enemies to help us in the development of long-distance airships; certainly 
Americans and Englishmen must all pull together. 

Wing-Commander Cavr-BrowNE-CAvE congratulated the Society on the 
résumé which Major Scott had given on the present state of airship technical 


matters. He wished to assure them that the picture which Major Scott had 
drawn was a very moderate one. It was completely free from speculation, and 
every statement he made could be very fully substantiated. To illustrate how 


moderate Major Scott had been, he mentioned the reference that had been made 
in the paper to R.38. It was merely there stated that the ship broke in the air. 
The point the author had tried to make in that part of the paper was that the 
failure of the ship must not be taken as an indication of what might happen 
in the future. To strengthen his point, Major Scott might perfectly well have 
quoted the finding of the Service Court of Inquiry which had been published, 
because it explained what the ship was doing at the time of the failure, and 
threw light on a good many pertinent matters. .\s, however, that case was still 
being investigated by the Advisory Committee, Major Scott cautiously refrained 
from bringing it forward. Most of them had seen that report, and knew that 
Major Scott was very moderate in the manner in which he dealt with that point. 


he actual construction of airships was necessarily very restricted by shortage 
of money. The design of R.38 was really a 1918 design, and much had been 
learnt since. It had been possible to go ahead with a great many research 


a 








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January, 1922] THE AERONAUTICAL JOURNAL 33 


problems. Reference had been made to synthetic proofing as a substitute for 
goldbeaters’ skin, to the use of hydrogen as an auxiliary fuel, the use of heavy 
oil, and many other similar questions, all of which had been investigated from 
the research point of view, but it had not been possible to embody them in any 
actual airship, because the money had not been available to build ships. How- 
ever, as soon as Construction started again, we ought to be able to embody in 
any new ship a great many features which had been tried out in experiment, 
and which he believed could be definitely embodied without any degree of 
uncertainty. Probably the greatest advance which had been made was the use 
of the mooring mast. How great that advance was he himself still found it 
extremely difficult to realise. It involved the change from having to use 300 or 
4oo men to work the airship cut of the shed, and then being able to carry out 
that operation only under very fair weather conditions to a state in which it was 
possible to land in a 4o-miles-an-hour wind, to get away in an equal wind speed, 
or to ride out a 60-miles-an-hour wind. That change was important enough, 
but one must also realise that the new system required only 10 men instead of 
several hundreds. | Commercial success in the use of airships depended on the 
certainty of being able to start them in any weather, and the mooring mast had 
unquestionably settled that problem. He had not the least doubt that when it 
became possible again to tackle other problems which were equally important 
in connection with airship practice, exactly the same degree of success would be 
achieved. 

Mr. Wyn Evans (Royal Corps of Naval Constructors) said that ‘‘ The 
Present State of Airship Development "’ was rather a peculiar term, but Major 
Scott had indicated that he wished to have that corrected as the title of his 
paper. One would rather have wished that Major Scott had taken the main 
points and weighed contemporary evidence with his own vast knowledge and had 
given some idea of what his ideal ship should be, one, of course, that could be 
turned out to-day. If he might be allowed to do so, he would like to make a 
few remarks based on our own and German experience. To commence a practical 
commercial air service over a usefully long distance he agreed with Major Scott 
that a 2} million cubic feet ship would be required, and he suggested that its 
form should be something of the Nordstern or the new Bodensee, i.e., the form 
with the extra gasbag, but with slightly larger stabilising surfaces, both horizontal 
and vertical. This he had gathered from German evidence. Of course, its exact 
L/D ratio would be governed, like the R.38 dimensions were governed, by the 
dimensions of the existing sheds. | Sufficient strength, by the way, could be 
obtained with the 15-metre spacing, which would reduce the structural weight 
and also the weight of the gasbag fabric. In commercial units it was not necessary 
to have so many individual gasbags as in ships designed for war purposes, as 
one did not anticipate individual gasbag failure. He had been informed in 
Germany that the L.7o class were not suitable for commercial purposes, being 
built too lightly. They were designed to attain great height, and R.38 was 
designed to beat them. Captain Heinen informed him that he had reached over 
8,000 metres (about four miles) during the trials of the L.71. In the proposed 
ship which he was trying to picture he would retain the streamline fins with the 
ordinary balance rudders. It would be better not to have the passenger car as far 
forward as in the Nordstern or Bodensee, but in a somewhat similar position to 
the R.36, because in the Nordstern and Bodensee it rather counteracted the effect 
of the vertical fins aft. This, he believed, was the principal reason why the 
Bodensee was considered the worst rigid airship built, from the passengers’ 
point of view. By the way, a passenger cabin had been designed similar, in 
effect, to that of the R.36, but with far less resistance, and of rather simpler 
construction. It was actually prepared for a ship of R.38 dimensions, and hence 
would be entirely suitable for the proposed 24 million cubic feet ship. This ship 
would have a disposable lift, taking into account the more rugged design of, say, 
46 tons, which, of course, would easily accommodate 40 passengers and 5 or 6 





THE AERONAUTICAL JOURNAL (January, 1922 





tons of mails, as Major Scott had indicated. .\s regards the gasbags, so long as 
we were not required to turn out ships every fifty or sixty days, like the Germans 
did, he did not think we need worry too much about the lack of goldbeaters’ 
skins. The selected skins that we had been using recently, and had obtained 
without undue trouble, had averaged 7 to the square metre against 21 to the 
square metre in the old cases, and the cost of cleaning and scraping these skins 
was about one-third, and although these new skins cost double what the old ones 
did, the total manufacturing cost was only about 60 per cent., and supposing we 
were turning out as many as four ships a year, it would not seriously affect the 
goldbeaters’ skin market. It was fully agreed that all energy should be put into 
obtaining a synthetic substitute, but he wanted to emphasise the point that the 


lack of this substitute did not prejudice airship construction to-day. The gasbags 
that could be manufactured had an extraordinarily low permeability and a lite of 
at least two years, if treated with ordinary care, as stated by Major Scott. As 


regards engines, it was a pity we had not been able to instal some of the new 
260 h.p. German Maybachs handed over to us last vear, because more experience 
with them would have been very valuable. Messrs. Sunbeam, however, had now 
delivered their 400 h.p. Semi-Sikhs, but we had not vet had an opportunity of 


trying them out on an airship. Although in an airship built to-day we should 
have to instal petrol engines, the danger from fire could be greatly minimised, 
if not entirely prevented, by excessive care in fitting the petrol system. — This 
danger was the only one which concerned the German pilots. They had _ told 


him on more than one occasion that the simpler the petrol system in design and 
construction, the better they liked it, and it was one of the things they examined 
personally. In each of the ships, the construction of which he had supervised, 
he had always laid great stress on the tests that should be put on the petrol 
system, and he did not believe any ship had left his hands in which there had 
been the slightest weep at any joint or connection. It was essential that any sign 
of a leak should be immediately dealt with. Particular attention should also be 
paid to the slinging of the petrol tanks, so that in the event of an excessive 
inclination they would not break loose. This could easily be effected even in 
conjunction with the slipping devices. With regard to the fabric, he believed 
that ** B’’ cotton outer fabric, with Farnborough dope, was sufficiently good at 
the present time, as in the case of accident or undue wear it could be easily 
replaced in sections. In all these points he was dealing with matters raised by 
Major Scott as really concerning a ship that we could put into the air to-day. 


. . . ™ 
He need not remark on mooring masts. Their advantages were obvious, but 
there were in hand modifications to the existing designs which he personally 
thought would afford considerable improvement. .\ll his preceding remarks and 


general ideas for a suitable ship were useless without constructional experience. 
This, perhaps, most important item had been omitted by Major Scott in his résumé 
of the position to-day, but it was absolutely essential that personnel, skilled in 
construction, should be retained. Mr. Burgess would bear him out in that. He 
knew, as well as anyone, the art there was in girder-making. Enlarging on this 
point, one must not forget the nature of the alloy that was being used, the care 
that had to be taken in regard to heat treatment, and many other points which 
one could talk of from practical experience for many hours. Unfortunately, all 
our skilled personnel had practically been disbanded, and it would be rather difficult 
to gather a sufficient number together again. It would be a terrible mistake to 
lose the few that were left, and who could form the nucleus of another staff. 
This was a point of the utmost importance, and one which was generally forgotten 
by those who discussed airship subjects to-day. His own experience in supervising 
rigid airship construction, dating back to R.g in 1915, had taught him the immense 
importance of shed and shop organisation, workmanship, and attention to detail. 
It was all very well to produce a design and demand materials of certain specifica- 
tions and scantlings, but it would all signally fail if the shed and shop work 
failed. He wished to emphasise most strongly that conferences and committees 








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January, 1922] THE AERONAUTICAL JOURNAL 35 


called to discuss airship matters should necessarily have a practical constructional 
representative, as well as a member with practical flying experience. As some- 
body said the other day, airships had come to be considered too much as a 
science and too little as an art. At first sight it might appear that his remarks 
had little bearing on the subject of the paper, but Major Scott had detailed out 
the principal items which together gave an airship, but had omitted that most 
important factor in development—the actual construction, except for a_ brief 
reference to the possibility of building a rugged ship to withstand all weathers 
and keep to a time-table. Perhaps Major Scott had such faith in the constructors 
that he did not feel it necessary to mention it, but in any case he personally 
felt compelled to urge that the practical constructional side, through not being so 
much in the limelight, perhaps, was too often overlooked in present-day delibera- 
tions, and no conference on the present situation, or committee formed to discuss 
future arrangements, was complete without a constructional representative—one 
who had had long experience and had come up against the many snags in the 
manufacture, erection and running of airships. 


Commander F. L. M. Bootusy said that Major Scott had given a very fair 
paper on the position of the airship as it was in this country to-day. We had 
had three years now since the Armistice to acquire running knowledge and develop 
commercial airship lines all over the world, but had failed to grasp the oppor- 
tunity, and all knew how we now stood. Others were going ahead. He had the 
pleasure about a fortnight ago to meet in Paris the Chairman of the Spanish- 
American Company, which was going to run airships from Spain to the Argentine, 
and he had very kindly told him what that Company was going to do. The 
Company had got its money and had made terms with the Spanish and Argentine 
Governments, and both Governments were going to repay the cost of their sheds 
over a period of 50 vears. A subsidy had been arranged with the Argentine 
Government, and the airships would run direct from Spain to Buenos Aires. There 
were two Zeppelin directors on the Board, and they proposed to build ships ofi 
150 to 180 tons, which was about double the size proposed by Major Scott. It 
was admittedly a big jump, but they had the knowledge to take that jump, and 
hoped in two years to have the service running. It was proposed to concentrate 
chiefly on mails, but they would take passengers at 4.150 a head from Spain to 
South America, or vice versa. He had spoken to prominent people in the 
Argentine and had been told that there would be as many passengers as they 
could carry, even at 4200 per head. That was the most favourable route in the 
world as far as weather conditions were concerned, and should have been developed 
by this country had airships here been properly supported. That all went to 
show that Major Scott, in asking for a 24 million cubic foot airship for the 
Australian route, was not asking too much in view of the experience of the 
Germans with airships, and the steps they propose to take. 


Colonel V. C. RictMoND expressed the view that Major Scott had achieved 
his object in a most admirable and able manner, for he had given a clear estimate 
of what an airship could do from a technical point of view. There had been a 
lot of discussion as to whether airships should be employed for long-distance 
transport, and it was essential that we should put our house in order and be 
able to say concisely what was the ability of the airship from the technical point 
of view. Mr. Burgess had remarked that the airship was in a somewhat precarious 
position, but he could not help feeling that Major Scott, by this paper, had put 
it in a less precarious position. He invited everybody to read again the statement 
that ** an airship of 75 tons could be built without introducing any experimental 
and untried features, that the hull would last in continuous service for at least 
five years, and would have a useful lift for freight of 12 tons, and could make non- 
stop journeys from England to Egypt at a speed of 50 miles an hour.’’ That might 
be described as the airship’s charter; one might almost say it was a pessimistic 


estimate; and how anybody could read that statement, go away, and not think 








THE AERONAUTICAL JOURNAL (January, 1922 


that we should immediately get on with the development of commercial airships, 
he could not imagine. They often heard that the airships had had £.40,000,000 
spent on them, but they would all admit that enormous technical strides had been 
made since the early airships were built. He would very much like to know whether 
it was possible to get some estimate of the money which had been spent in the 
development of the aeroplane. Naturally, there was more incentive for this during 
the war. Aeroplanes were able to do more useful work; nevertheless, it must 
be remembered that an enormous amount of money had been spent on their 
development, and it had been very difficult to get any money at all for airship 
development. Big improvements were in sight, bigger, perhaps, than any of 
them imagined. Major Scott had been most retiring in referring to this. In 
fact, he had almost left it out of the picture. Nevertheless, big improvements 
were in sight, and once there was the necessary incentive he was perfectly sure 
that English genius and English engineers would be capable of maintaining the 
lead which England once held—he was obliged to say ** once ’’—in airship matters. 


Mr. A. H. Asupour congratulated Major Scott on having put more informa- 
tion into as few words as he had ever heard before on this one subject. With 
regard to the mooring mast, he was in Germany in 1912 and saw a fair amount 
of Zeppelin flying at that time, and he then realised that a possible future existed 
in that method of conveyance. From the commercial point of view, however, 
with which he was largely concerned, it was a wash-out when they took into 
consideration the large number of men necessary to start or load a ship, together 
with the fact that even with such a large number of men, the ships could only 
be utilised on fine weather days. When he came to England twelve months ago 
and saw what had been done in the way of mooring ships, he realised that their 
commercial possibilities were a distinct factor, and it ought to be recorded in 
the annals of the Society that the main factor—the mooring mast—in reducing 
this to a practical commercial proposition, was largely due to Major Scott, who, 
naturally, had not referred to it himself. On the commercial side, some of them 
knew that he had taken some little interest in trying to evolve an Imperial 
airship scheme, and when the Conference of Premiers was sitting in London last 
June, he managed to get this subject included in the agenda paper. Unfortunately 
he could not get the different Dominion Premiers, while in England, to put down 
a hard and fast statement of what they would do. He knew that the members 
of the British Government were sitting on the fence and were not anxious to do 
anything unless they were absolutely pushed by the Dominion representatives, 
but unfortunately he could not get the Dominion representatives to come down 
to a hard and fast proposition before they left. However, he had, during the 
last few months, been pegging away at the Dominion Premiers, and it was only 
last week that he got a second, or third, telegram from the Prime Minister of 
Australia, Mr. Hughes, saying that he was definitely bringing this matter before 
the Australian Parliament, and that he would do his best to push it through, and 
in that event he would put up a proposition to the British Government. Since 
his own paper on the possibilities of an Imperial service last week, he had had 
another telegram from Mr. Hughes—last night. It was of a_ confidential 
character, and he could not give details, but he could say this, that that telegram 
indicated every possibility of a definite proposition coming from Australia in the 
very immediate future. If they could get a definite proposition from the different 
Dominion Governments, he did not believe that the British Government could 
then fail to come along and join forces with their overseas representatives, and 
in that case, if they could only get suflicient money together, they ought to 
start an experimental service for a period, say, of two years.* If in that period 
they could not justify the confidence which some of them had in airships, then 
it would be time enough to break up the whole organisation and pass it out. 
He, however, was not of that opinion. He was confident that if they could get 
the ground plant into existence and run through a few experimental airships so 
that the people in the overseas Dominions could see for themselves what had been 














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January, 1922] THE AERONAUTICAL JOURNAL 37 


done in airship construction, there would then be no more doubt, and at the end 
of the experimental period it would simply be a matter of building ships which 
the experimental flights would have indicated as the most suitable. In view of 
the messages which he had received last week and the week before, there was 
every possibility of some definite proposition being put forward, and in that case 
it was to be hoped that we should be able to do something and not let England 
and her Dominions drop out of the airship competition, which unfortunately 
seemed to be the prospect when the Government, last August, decided to break 
up the personnel and the plant. He would like to congratulate Major Scott on 
the valuable information which he had given, information which, to commercial 
people like himself, was of great benefit, and would help them if they could only 
get the different Governments to come together and assist. 

Squadron-Leader R. M. Hitt said that he was an aeroplane pilot, and as 
there was a bond between aeroplane people and airship people, namely, the air, 
he took the opportunity of saving a few words. He quite agreed with Major 
Scott that the airship could do a great deal that the aeroplane could not. Most 
aeroplane people were immersed in aeroplanes from morning: till night, and 
possibly got into a groove; but when one went to an airship station and saw 
what airships could do, and what they did do, and what they had done, and 
what he hoped they would do, then one became confident that the present lapse 
was purely temporary. He went up to Howden about a vear ago and was taken 
into R.33, and he must say that it was simply like stepping into fairyland. It 
was the most beautiful engineering structure that he had ever seen, and one 
could not help feeling that an engineering achievement of that sort must be 
useful in civil aviation. : 

He was very interested in what Major Scott had said with regard to airship 
engines. He spoke under correction, but he believed that most of them had been 
Sunbeams. These had been fitted into aeroplanes; they were what one would 
call a light engine, and were obviously unfitted for use in airships. It must have 
been a tremendous handicap to the airship people not having a good, heavy, 
solid, economical sort of engine to work with, such as the Germans used in their 
own airships. He would like to ask Major Scott one point, and that was—when 
he was using his instruments to make observations of heavenly bodies, was the 
view obscured owing to the control car being underneath the body of the airship? 

He remembered hearing the late Air-Commodore Maitland give his 
unforgettable lecture on the voyage of. the R.34. Air-Commodore Maitland, as 
they knew, was the mainspring of the British air service, and he gave the lecture 
in cold, measured terms, and half-humorous chat from a log-book. To himself 
it was an exciting drama, with Major Scott as the central figure. Major Scott, 
having done what he did, was certainly the most able man to impress everybody 
with the possibilities of the airship, and not the least, aeroplane pilots; and he 
hoped that in future the airship and aeroplane would go along side by side and 
be a mutual help to each other. 


The CHAIRMAN said he supposed that most aeronautical engineers had been 
asked as to their creed about airships. He had been asked ‘‘ Do you believe in 
airships? ’’ and he proposed here and now to say publicly ‘‘ I do.”’ It helped 
when people associated with aeroplane work definitely said that. He added a 
proviso, however, that if we stopped our research work, the existing structure 
of our knowledge would practically vanish. Hf the Geddes Committee, for 
example, prevailed on the Defence Minister to cut the present modest expenditure 
on aeronautical research, then all the rest of their air expenditure would be wasted, 
there would not be any progress in this country, and the technical position now 
held would pass to America or some other country. Research was the foundation ; 
the visible and apparently more useful superstructure would collapse without 
that foundation. The public would probably hear of research being struck off 
without a qualm. They could not see what they would be losing, and if the 








THE AERONAUTICAL JOURNAL (Fanuary, 1922 


foundation were maimed, then he did not believe in airships in England. Years 
ago he had a pleasant airship cruise for six hours in the Victoria Louise. That 
was in 1912. That did not fill him with a conviction that he knew all about 
airships; quite the contrary; but one could not live for six hours in an airship 
without thinking hard about their use, construction and future. He generally 
found that those who did not believe in airships knew nothing about them. Why 
had not airships progressed more rapidly as compared with aeroplanes? The 
answer was partly *‘ money,” and partly that experimental construction was slow, 
and partly that the research side had in the early stages been inadequately 
appreciated. The number of experiments one could make in a given time with 
airships were tens against hundreds or thousands with aeroplanes. The number 
of experiments we have in fact made is only a fraction of the number we could 
have made with the airships at our disposal. That was an error of perspective 
in his opinion on the part of the Air authorities in the past. Had we pressed 
on the research side, we might, without any difference of total expense, have 
had that capital remuneratively expended. 

Major Scott had drawn attention to the change which came about with 
increase of airship size and speed from the time when there was a predominance 
of static load in the basic designs of airships and the time when there was a 
predominance of dynamic load. With the increase of speed and the invention 
of the mooring mast, a great change came over many people’s views; many who 
a few vears before did not believe in airships as a means of transport because 
they could not deal with moderately high winds began to feel that the 
position was altering. Not only had airships flown at 70 miles an hour, but a 
zo-miles-an-hour wind was a rare occurrence. He felt that they might accept 
Major Scott’s view to be justified in that we could count on a useful travelling 
speed of something like 50 miles an hour from place to place. 


With regard to goldbeaters’ skin, he had been associated with the use of 
goldbeaters’ skin for balloons, and we in this country were responsible for the 
development of the use of goldbeaters’ skin, which was twenty-four times better 
than rubbered fabric for keeping the hydrogen in the bag. Then the Germans 
got hold of goldbeaters’ skin, and the price went up many, many fold; from one 
sovereign, the price went up to three or four when the Germans started using 
them. However, he was glad to hear someone say in the discussion that they 
did not think the amount of goldbeaters’ skin used would be such as to seriously 
affect the price even if we built three or four airships a vear. Possibly that was 
true, and so much the better. He happened to be aware of some remarkable and 
extremely interesting progress that was being made in the study of gelatines, 
from which much was to be hoped. He supported what Major Scott said as to 
the progress that was being made and as to the possibility of gelatine taking 
the place of the expensive goldbeaters’ skin. He did not go so far as Major 
Scott in regard to the danger from fire due to petrol. Some interesting experi- 
ments had been made, and there were some people present who knew about 
them and could say that he was not exaggerating. The danger of fire, so far 
as petrol would cause it by flowing over hot exhaust pipes, was less than was 
usually thought. He did not mean by this that one could go and light a pipe 
over an open petrol filler, but the danger from petrol dropping on to a hot 
exhaust pipe, or even on to the hot ash of a cigar, was less than was commonly 
thought. On the other hand, a little bit of cotton fluff dropping on to that 
same hot pipe would light, and if it did so, its flame would ignite the petrol 
there. The impression that risk arose directly from the petrol was all that he 
was controverting. He accepted what Major Scott urged, namely, that they 
need not be afraid because there was a big bag of hydrogen above them. 


Lastly, he would like to point out just for the sake of old times and for 
the sake of the old aircraft factory, of which he was very proud, that the first 
airship that ever swung from a mooring mast clear of the ground or water was 











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January, 1922 THE AERONAUTICAL JOURNAL 39 


invented, designed and made at Farnborough by the old Royal Aircraft Establish- 


ment of that day. They hung out their airship for two or three months. It 
turned out to be quite an important thing. With regard to Mr. Ashbolt’s 


very interesting remarks, what was in his mind was that we must link up with 
the Colonies, and that link was fundamental to the Entente with them. If we 
did not have airships, high-speed sea ships would have to be available to link 
us up more rapidly and connect us more freely with our Colonies, but there was 
no doubt that airships would be a cheaper and quicker means of travel. 

Major Scott, replying to the discussion, said that the taking of sights on 
an: airship with the sun and stars was done from the top. There was a platform 
which was approached by a ladder up the centre of the airship, and the sights 
were nearly all taken from the top, so that there was a perfectly clear view. He 
absolutely agreed with Mr. Burgess that they must combine forces at the present 
time. The airship was one of the most important forms of transport for the 
future, and transport, as somebody said, was civilisation. At the present time 
there was a Conference at Washington and the League of Nations, all tending 
towards civilisation; anything to improve the transportation of the world was 
doing the same thing,-and therefore they must all combine in the development 
of aerial transportation. Commander Cave-Browne-Cave had accused him of being 
pessimistic. He was glad he did. He had given them in the paper what he 
considered to be the absolute true facts of the case at the present time. He had 
not given them his opinion ; his opinion was much more optimistic. He had merely 
given them facts which he could absolutely confirm. There was nothing in what 
he had said that was the slightest bit questionable, and the speeches made by 
Commander Cave-Browne-Cave and others had shown that what he had given 
was actually pessimistic, and that the Chairman’s view was very much in the 
other direction. The airship mentioned by Mr. Wynne-Evans would suit him 
very well. If he were given an airship like that, he had no doubt that he could 
carry out Mr. Ashbolt’s scheme without any trouble whatever. If he were to 
start discussing the question of the disbanding of the skilled personnel, he would 
never stop; but, as the Chairman had said, this paper was a technical paper 
and not a political one. He was very pleased with what the Chairman had said 
about petrol. He had not wanted to impress anybody by what he had said in 
the paper that the danger of fire was big. He had merely wanted to say that 
that was the biggest danger, and the Chairman had now told them that that 
danger was not big. He wished them to judge the danger of the airship from 
that statement. 


A hearty vote of thanks was accorded the author. 





THE AERONAUTICAL JOURNAL (January, 1922 


PUBLICATIONS. 


The following papers, etc., are published by the Society: 


Transactions. 
1. ‘* The Calculation of Stresses in Aeroplane Wing Spars,’’ by 
Arthur Berry, M.A. ... 5 = oe. pee i 
‘* Position Fixing in Aircraft during Long Distance Flights over 
the Sea,’’ by Instructor-Commander T. Y. Baker, R.N., 
and Major L. N. G. Filon, D.Sc., F.R.S., late R.A.F. 
3. ‘* Aero Engine Efficiencies,’’ by Dr. A. H. Gibson 


*. ig 


Aeronautical Classics. 


Reprints of the Work of Early Pioneers on whose theories 
modern flight is based. 
‘* Aerial Navigation,’’ by Sir George Cayley (1809) 
‘** Aerial Locomotion,’ by F. H. Wenham (1866) 
‘*The Art of Flying,’’ by Thomas Walker (1810) 
‘* The Aerial Ship,’’ by Francesco Lana (1670) ... 
‘* Gliding,’’ by Percy S. Pilcher (1897) ... - 
‘* The Flight of Birds,”’ by G. A. Borelli (1680) 


Mew w= 


Miscellaneous Publications. 

‘* Steels Used in Aero Work,’’ by Dr. W. H. Hatfield fe 

‘ Methods of Measuring Aircraft Performances,’’ by Captain H. T. 
Tizard sia se a — Sa eh ot are 

‘The Screw Propeller in Air,’’ by M. A. S. Riach 

‘The High Tension Magneto,’’ by A. P. Young 

‘Commercial Aeronautics,’’ by G. Holt Thomas . i er 

‘The Training of Aeronautical Engineers,’’ by R. M. Walmslev 
and C. E. Larard si sis re = 

‘Steel Tubes for Aircraft,’’ by W. W. and A. G. Hackett 

‘* Timber,’’ by W. H. Barling ... se aoe oe ee eee 

‘* Design of Aeroplane Struts,’? by W. H. Barling and H. A. Webb 

Stress Optical Experiments,’’ by Major A. R. Low 
Medical Aspects of Aviation,’’ by Dr. L. E. Stamm ae 

** Struts of Conical Taper,’’ by H. A. Webb and Miss E. D. Lang 

“* Shop Practice in Respect to Aircraft Steel,’? by H. P. Philpot ... 

‘The Rigging of Aeroplanes,’’ by R. J. Goodman Crouch 

‘* Progress of Aviation during the War Period,’’ by Dr. L. Bairstow 

“Flight of Seagulls,’’ by Dr. E. H. Hankin os ae 

‘* Chronology of Aviation,’’ by H. Maxim and W. J. Hammer 

‘* Report of the Bird Construction Committee ”’ 

‘* Glossary of Aeronautical Terms ”’ sid Ae Bay ss 

““London-Paris Service. Safety and Economy Committee’s 


Report ”’ 


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