H.King Sopwith Aircraft 1912-1920 (Putnam)
The early chapter in this book which dealt with 'Circuit Seaplanes' recorded how, early in 1913, the Daily Mail newspaper had offered ?10,000 for the first flight across the Atlantic Ocean. Though hopeful preparations had been put in hand - notably by Martin & Handasyde - the war came both as an interruption and as a technical stimulant; so that in July 1918, shortly before the Armistice, T. O. M. Sopwith was able to declare: 'The Transatlantic flight could be made and the prize won this month ... Crossing from America to England by air is not the problem it was a few years ago ... A dozen machines of today could do it. They could do it at once if aeroplane makers and pilots were not all busy with war demands.'
No equivocation here; and, in fact, the number of machines that was eventually assembled in 1919 for the great adventure did approach Sopwith's 'dozen' (actually eight). Eminent among these were - as hoped so long before - a Martinsyde (The Raymor, manned by F. P. Raynham and Capt C. W. F. Morgan); the Sopwith Atlantic, now to be studied, and crewed by H. G. Hawker, with Lieut-Cdr K. Mackenzie-Grieve as navigator; and a certain Vickers Vimy manned by Alcock and Brown, and concerning which it would be impertinent to write more here. We may note, nevertheless, that all three of the equipages mentioned were closely tied with Brooklands (and carried 'Tabloid' first-aid kits!).
Although the Sopwith Atlantic as the inevitable Harry Hawker's challenger was properly called, though Rolls-Royce was often linked with the name, or with some variation, and Sopwith also used the appellation 'Transport' was based on the design of the B.1 Bomber, and on accumulating experience with the Cuckoo, and was built in a mere six weeks (it was flying by the end of February 1919) it represented no patched-up operation either in design or equipment. The man chiefly responsible for the metamorphosis was W. G. (George) Carter.
The chief innovations, apart from the extra-large fuel-tankage (between the cockpits and the engine) were the jettisonable landing gear, saving drag, weight and petrol - beneficial to cruising speed and seemingly attributable to Hawker's own insistence; wooden skids to reinforce the bottom longerons and serve as landing gear; an upturned lifeboat which formed the aft decking of the deepened rear fuselage; the fitting of special wireless (initially directional, but changed, after tests, to a T.55A transmitter, loaned by the Air Ministry); a retractable wind-driven generator to provide power for the wireless; and staggered seats for the two occupants - for easy communication and (as one account put it) to facilitate changing watches during the long journey.
The most common criticism of the aeroplane was that it should have one engine only, though another concerned the releasable landing gear, this being considered (though not by Hawker himself) to put the crew at risk in alighting and deny them the hope of taking-off again.
The all-important engine was the very best that Britain could produce - a Rolls-Royce Eagle VIII water-cooled Vee-12 unit of 360/375 hp. The radiator was frontally mounted, with adjustable cooling-shutters, and there were long exhaust tailpipes extending straight aft to a point behind the cockpits. Early in its operational career, the Eagle engine (designed by Henry Royce in collaboration with his young chief assistant A. G. Elliott, and first run in October 1915) had been known as the "250 h.p. Rolls-Royce"; but an official 'R-R' instruction book dated December 1917 ascribed the following outputs (at normal rpm.) to successive Marks: Eagle I 225 bhp; II 266; III 284; IV 284; V 322; VI 322; VIII 350. Certainly, by the time of the Atlantic attempts the Eagle VIII was already well-proven, notably in Handley Page bombers. Its cubic capacity was 20.32 litres, and an epicyclic gear gave the left-hand tractor propeller a reduction ratio of 0.6 to 1. (N.B.: The A. G. Elliot just mentioned must not be confused with A. F. Elliot, who helped to design the A.B.C. Wasp, Dragonfly and Gnat).
Although a four-blade propeller had been used on early tests of the Sopwith Atlantic that were made in England, the pattern selected for the transoceanic flight - with take-off performance especially in mind - had two blades only, giving a diameter of 9 ft 6 in (2.9 m).
The tense adventure-story of the attempted crossing from Newfoundland has been written at length by so many and various pens that a brief profile only is called for. Thus:
Hawker and Grieve airborne 5.42 GMT, 18 May, 1919. Almost immediately ran into fog off the Grand Banks. Pressed on through fog. After fog cleared, Grieve estimated that aircraft had flown 400 miles. Massive clouds now loomed, but Hawker climbed above them. After nearly six hours' flying engine-water temperature rose. Radiator shutters failed to work, so, with engine throttled, Hawker dived for 3,000 ft to cool it and dislodge any obstruction. Situation improved but only temporarily, and on renewed climb the centre of the top wing iced-up from freezing steam. Early on the 19th (a Monday) cooling trouble returned and worsened. More bad weather; and Hawker headed south for shipping lanes, coaxing engine. Came the dawn, and, through the mist, the SS Mary, of Denmark. Signals (Very lights) from the Sopwith: Hawker steered aircraft about a mile ahead of ship. Text-book ditching (see Hawker's own remarks later) and the Sopwith's lifeboat launched as aircraft was sinking. Boat arrived from Mary. Everyone safely aboard - but Mary had no wireless, and the world was left in an agony of waiting.
An account of the Atlantic attempt, ascribed to Hawker himself, was factual and vivid, and in its very first sentence it proclaimed the Brooklands camaraderie by recording that, before take-off, Hawker and Grieve sent their respects - 'and hopes of seeing him at Brooklands' - to Fred Raynham, whose rival Martinsyde nevertheless crashed on setting forth from Newfoundland.
Hawker described his own take-off as 'just a bit ticklish’, the 'bit' being measurable by the number of inches by which he missed a drainage ditch. Then true to form as an observant and technically minded test pilot - 'As soon as the coast had been passed, I pulled the undercarriage release-trigger and away it [sic] went into the water. Simultaneously the finger of the air speed indicator went over to another seven miles an hour.' Nor was this Hawker's only observation concerning the jettisonable wheels, for of the period immediately preceding the historic splash-down near the good ship Mary (which occurrence, Hawker thought, went 'quite nicely’, with the aircraft riding clear of the water by reason of the partly empty petrol tanks) he recalled: 'There was no lack of rain squalls, the wind was getting stronger and gustier and bumpier every minute, and the sea rougher. I was very glad to be without the undercarriage, and would rather have been as I was than have floats under me, for the waves looked too heavy for any ordinary seaplane to stand.'
Clearly, the wartime lessons learnt by the Navy and the RAF in the ditching of Pups, 1 1/2 Strutters and Camels had been put to good account though Grieve, as a Naval officer, observed the traditions of the Silent Service while Hawker shouted for joy.
A moment, this, to have set the hearts of all mankind athrob; though for days the world was left, not to wonder, but to wait and worry. As Hawker said: 'We had hoped to fall in with a ship equipped with wireless so that we could communicate with our people in England, and of this Captain Duhn, who spoke excellent English, thought we had a good chance, but later on the storm got considerably worse and he had to heave to, only making very little way in a northerly direction and so going further away from the busier shipping route. So it was not until we were off the Butt of Lewis that we could communicate with home and the world that at one time had seemed so distant.'
Then the old Brooklands comradeship shone through once more, as Hawker's story concluded: 'The men who should have the reception are Raynham and Morgan, for what they did was a magnificent act of pluck. The east-north-east wind was not by any means a bad one for our getting off, for it suited our aerodrome pretty much as well as any other and better than most, but it was almost the worst possible wind for the Martinsyde aerodrome. But knowing this Raynham and Morgan never hesitated to attempt the flight... They were visited with cruel hard luck indeed.'
And just what kind of luck, it might be asked, had Hawker himself encountered? But in conveying these personal glimpses of fine men one is seeking merely to establish sturdy links not only between the Sopwith and Martinsyde companies, but likewise between Sopwith and the succeeding H. G. Hawker Engineering Co Ltd, established late in 1920.
As already noted, it was a Sopwith draughtsman. W. G. Carter, who had the task of remodelling the basic B.1 Bomber airframe into a virtually new aeroplane for the Atlantic attempt - just as, in later years, Carter redesigned the Hawker Woodcock fighter into something acceptable by the RAF and designed from scratch the Horsley bomber, which was itself later specially arranged (as the Sopwith Atlantic had been in its day) for extreme long-distance work. In even later years Sir Sydney Camm - to whom the design of the Horsley is sometimes incorrectly ascribed - recalled for the present writer how he had joined the newly formed Hawker company from Martinsyde not long after Harry Hawker's death in 1921, and at about the same time as his friend and Martinsyde colleague Raynham had taken a similar step. That Hawker's high opinion of his fellow test pilot was shared by Camm was clear from Camm's recollection of flying with Raynham (I think in the Hedgehog) and of his unwonted emotion in mentioning 'Old Raynham’. (To Sydney Camm all men and things he held in high esteem were 'old').
Thus it was that the Hawker company had in the 1920s a personal structure buttressing the business side; and in the planning and manning of the Atlantic - one of the last and finest of the Sopwith line - this was already becoming manifest.
Links between companies and individuals being now in mind in the context of the Sopwith Atlantic, with its Rolls-Royce Eagle VIII engine, it is particularly appropriate to quote from a letter addressed to the press by Claude Johnson. Rolls-Royce's managing director, following the first nonstop Atlantic flight - by Alcock and Brown in a Vickers Vimy, though (as may be judged from the wording) the letter may well have been based on a draft press release prepared in anticipation of success by the Sopwith. Thus the letter read in part:
'It has been calculated that if the Atlantic crossing were completed in 20 hours by one Rolls-Royce engine running at an average of 1,800 revolutions per minute, its performances would be as follows (in a two-engined 'plane such as the Vickers Vimy the operations would naturally be doubled): Each engine will make 2,160,000 revolutions, and each piston will travel up and down the interior of its cylinder a total distance of 440 miles. As the Rolls-Royce engine has twelve pistons, they will in all travel 5,280 miles. The valves will be operated some 25,920.000 times in each engine ...'
Although, as already noted, a Sopwith association may be implicit here (the Martinsyde contender had a Rolls-Royce Falcon III engine, of lower power and shorter stroke, so the figures for piston-travel would not have applied) a similar link is not instantly apparent from an ensuing paragraph concerning what Johnson termed 'recent history of the Rolls-Royce aero engines.' This paragraph the full significance of which will later be made clear ran as follows:
'On 11th November, 1918, when armistice was declared, there were in possession of the Royal Air Force Rolls-Royce aero engines of a total horse-power of over 1.000,000, which far exceeded that of any other make of aero engine in use. Previous to armistice day there had been constructed 122 Handley Page bombers, of which no less than 113 were fitted with Rolls-Royce engines. Prior to the same dale 1,524 complete Bristol Fighters had been delivered, of which number 1.364 were also equipped with Rolls-Royce engines. Rolls-Royce engines were used exclusively in the planes of the London-Paris Government courier service for the conveyance of Ministers, officials and dispatches to and from the Peace Conference ...'
Paradoxically, the promised clarification of the foregoing lies in the fact that although allusion is made to Handley Page, Bristol, Vickers (and by 'Peace Conference' implication) de Havilland, there is no reference to the great Sopwith organisation which is our present concern. That no operational Sopwith military type was, in fact, ever fitted with a Rolls-Royce engine (and only the highly experimental L.R.T.Tr. carried the 'R.R.' trademark-and that, perhaps, by reason of Government insistence) will be apparent from the contents of this present book; but that the names of Rolls-Royce and Hawker were later to make a resounding impact on aeronautical history is made clear by another volume in this series (Hawker Aircraft since 1920, by Francis K. Mason). Thus the Sopwith Atlantic represented not only a glorious failure - and a no less glorious approach to the ending of the Sopwith line but equally the beginning of one of the greatest families of aircraft ever known, broadly delineated by Horsley (Condor), Hart and Fury variants (Kestrel), Hurricane (Merlin), Sea Hawk (Nene) and Hunter (Avon). Truly the pistons had 'travelled up and down' incalculable miles since Fred Sigrist, in 1912, was writing helpful hints on how to tune the Gnome.
That even the Eagle VIII did not bear out the present Sopwith's name Atlantic (though Hawker assured 'T. O. M." that it ran perfectly even when all the cooling-water had boiled away) the failure was by no means a catastrophe; for among the significant technical aspects was the taking of "X-ray" photographs (the term was still commonly printed in quotation marks, for Rontgen had not announced his discovery until 20-odd years earlier) and the publication of one of these photographs in 1919 with the following notations:
'An interesting experiment in connection with the engine of the salved aeroplane in which Mr. Harry Hawker was forced to descend in the Atlantic has produced a radiograph of the lower part of the engine's radiator. Owing to the science of radiography, it is now possible to take "X-ray" photographs (or radiographs) through 2 in. of solid steel. At the request of Mr. T. O. M. Sopwith, the designer [sic] of Mr. Hawker's machine and Mr. Gordon Selfridge (on whose premises the wrecked machine was exhibited), Harry W. Cox and Co., Ltd., "X-ray" specialists, of Wigmore Street, London, W.1, took a radiograph of the lower part of the radiator, in order to ascertain the presence, or otherwise, of any foreign matter, such as might have caused the engine failure.'
It was then explained how one radiograph clearly showed the flanges and all details of the soldered joints; how small white patches on the flanges denoted entire absence of solder; that the lightest grey patches indicated a small quantity of solder only, while darker blotches represented large masses of solder; and the report concluded:
'Owing to the aeroplane having been submerged in the Atlantic for some time, any foreign matter that may have lodged in the radiator must have been washed out, as a completely free path through the tube can be seen in the radiograph.
'The importance of the use of an apparatus of this kind is palpable. Faults in castings, for instance, which it would be impossible to detect by any external examination, or - as in this instance - three distinct grades of soldering, are accurately revealed. In the aircraft industry, where so much depends upon the absolute perfection of all parts of the machine, an examination of the essential portions, by radiography, is invaluable.'
Invaluable in many other ways were the lessons learnt from the Sopwith Atlantic. Knowing that he could not carry on indefinitely with the Eagle's cooling-water boiling away - owing, he thought, to a blockage with refuse such as solder - Hawker had 'played for safety', as he put it.
Unlike 'absolute perfection' - the term used by the "X-ray" commentator 'safety' is relative.
Atlantic (Rolls-Royce Eagle VIII)
Span 46 ft 6 in (14.1 m); length 32 ft (9.7 m): wing area 547 sq ft (50.8 sq m). Empty weight 3,000 lb (1,360 kg). Maximum speed 118 mph (190 km/h): cruising speed 105 mph (169 km/h); ceiling 13,000 ft (3,960 m).
Flight, April 10, 1919.
THE TRANSATLANTIC RACE
THE preparations for the great race to be first to cross the Atlantic by air are progressing apace. By way of summary, the Sopwith machine, to be piloted by Mr. H. Hawker, who will have with him as navigator and assistant pilot Capt. Grieve, is already at the starting point in Newfoundland, and is only awaiting favourable weather conditions before making a start. The Martinsyde biplane, with its pilot, Mr. F. P. Raynham, and his navigator, Capt. Morgan, is on its way across, and may, by the time these lines appear in print, have arrived at St. John's. The Fairey machine, up till now the only seaplane entered from this side, is rapidly nearing completion, being, in fact, a standard Fairey 3C type especially adapted for the race. The pilot, as already announced, will be Mr. Sydney Pickles, so well knows to all readers of FLIGHT. The name of the navigator who will accompany him has not yet been disclosed, but will, we understand, be announced shortly. The Short machine entered, and which will be piloted by Major Wood, who will have with him as navigator Capt. Wyllie, has the distinction of being the only entrant which, so far, it is proposed to start from this side, the starting point chosen being Bawnmore, near Limerick, in Ireland. This machine, which has been undergoing severe tests during the last couple of weeks, is to be flown first to Ireland, whence the final start will be made.
As to the probability of one or all of the competitors succeeding in getting across, there is of course, a certain element of luck involved, but arrangements, as announced elsewhere, are being made., by the Air Ministry and Admiralty, to take all possible precautions, and to ensure that, even in cases of engine failure, the occupants should have a very good chance of being picked up by passing vessels.
As interest centres more and more in this race, a few words dealing with the British machines entered will, we feel sure be welcomed by readers of FLIGHT.
The Sopwith Machine
The Rolls-Royce engined Sopwith transport type specially designed for an attempt to win the Daily Mail Prize for crossing the Atlantic, is of the vertical biplane type, the wings having no stagger. Pilot and navigator are seated well aft, so as to give a large space in the fuselage between them and the engine, in which to fit the large petrol tank required for the great amount of fuel that has to be carried for a flight of this duration. This tank has a capacity of 330 gallons, while the oil tank contains 24 gallons, and the water reservoir 17 gallons. The weight of the machine empty is 3,000 lbs., and fully loaded she weighs 6,150 lbs. The accompanying general arrangement drawings will give a good idea of the dimensions of the machine. The engine fitted is a Rolls-Royce "Eagle," of 375 h.p., which will give the machine a maximum speed of 118 m.p.h. This speed will not, of course, be maintained all the way, the most economical speed from the point of fuel consumption lying somewhere between the maximum and the minimum speed, and varying with the lightening in load as the fuel is consumed.
The cockpit of the occupants is arranged in a somewhat unusual way, the two seats being side by side, but somewhat staggered in relation to one another. The object of this seating arrangement is to enable them to communicate with one another more readily and to facilitate "changing watches" during the long journey. The very deep turtle back of the fuselage is made in part detachable, the portion which is strapped on being built so as to form a small life boat in case of a forced descent on the sea. In this manner it is hoped to provide sufficient flotation for the occupants to remain afloat until a passing vessel may pick them up, should a descent be necessary. As the machine is not fitted with floats, it would, of course, be out of the question to get her off again once she was in the water. In other respects the machine does not differ greatly from standard Sopwith practice, which is already well known to readers of FLIGHT. The two photographs and the general arrangement drawings, should give a very good idea of the general appearance of the machine.