Slide Rule
In the air their work was above reproach; each man was capable of thinking for himself and taking intelligent action on his own initiative in an emergency. It was possible to go to any man in the ship and get a reasoned and coherent statement of what he had observed, and every man knew every part of the ship intimately. Without exception they were cool and fearless men, and I saw no sign of quarrelling or any trouble in their mess. In times when there was no flying they did not present so good a picture. They had no incentive to perform routine work, and they needed a lot of keeping up to the collar.
This was the chief defect of the airship flying organisation. The officers and men were neither members of the Royal Air Force nor civilians; they were not subject to service discipline, nor were they subject to the discipline of the workshops. There was, in fact, no discipline at all other than that imposed by the good sense of the men themselves. As time went on the discipline upon the ground deteriorated badly.
In these last months my own position in the Airship Guarantee Company underwent a change. During the construction of the ship I had gravitated towards the top of the organisation. My chief was B. N. Wallis, whose title was Chief Engineer. To my mind Wallis was the greatest engineer in England at that time and for twenty years afterwards. It was an education and a privilege to work under him, and I count myself lucky to have done so. Sir Dennis Burney, our Managing Director, was equally outstanding; he had the keenest engineering imagination of anyone that I have ever met, coupled with a great commercial sense. He had the ability to stand back and take a birdseye view of an entire industry and say—‘This is the commercial problem. We want to devise a means of doing this. My idea is that we could do this.’ And here he would put forward some entirely novel scheme such as nobody had ever thought of before, grandiose perhaps, but based upon the soundest engineering principles.
These two men were complementary and the success of R.100 was due to their combined abilities; my own part in it was small. It was deplorable that they could not agree better, but temperamentally they were poles apart. Perhaps two genuises in one company would always find it difficult to work together. In those years I conceived the greatest affection and respect for both of them which endures to the present day, and I mention their differences as shortly as possible and only because they affected my own position to a great extent.
Perhaps Wallis was more interested in the straight problems of design than in the flying of the airship, and by the beginning of 1929 the straight design of R.100 was over. Certainly in that year he began working at Howden upon the geodetic wing design of aeroplanes which later was to reach its full perfection in the design of the Wellington bomber, and his absences at the Vickers aircraft works at Weybridge became frequent. My own abilities were essentially practical; although I was the mathematician in charge of the calculations I was the only man in the party with any personal experience of flying an aeroplane, and as the mathematics eased and the practical problems of finishing the ship and getting her in to the air became paramount I found that people turned to me more and more, and that I could give quick decisions on most subjects if Wallis was away, reporting to him or to Burney as opportunity offered. By the autumn of 1929 the Works Manager was coming to me so frequently that I was virtually in charge of the whole outfit. This position was finally regularised by making me Deputy Chief Engineer under Wallis, and when he finally left the company after the first flight of the airship I carried on in technical charge and saw the ship through her trials. ‘In the country of the blind the one-eyed man is King’, and that was me. My promotion brought me a comfortable salary for a bachelor with no very extravagant tastes; I moved to York, where I lived in the St. Leonards Club, motoring twenty miles to Howden every day, and began to take part in a few modest social activities. Although nominally I was in charge of the whole staff at Howden it was understood that if we should get another airship to build Wallis would come back, and I should have welcomed that; I had no illusions about my abilities as a designer, while he was magnificent.
In November 1929 the ship was finished. It seemed almost incredible to us who had worked on her for five years that there should really be nothing more to do to her before she flew, but the day came when we ballasted her up in the shed for her lift and trim trials, determining accurately for the first time the loads that she would carry. It was a simple procedure; we mobilised a hundred men to hold her by the power cars and the control car so that she neither floated up into the roof nor sank on to the floor. After each readjustment of the weights the men let go of her together on the blast of a whistle; we watched to see if she would rise or fall. After a few trials she hung motionless for a minute on end, poised in the air above the floor of the shed. Readings of barometric pressure and temperature completed the process; she was then ready to be handed over to the crew for flight.
4
THE CONTRACT FLIGHT TRIALS OF R.100 were carried out by her Air Ministry crew working under the directions of the constructors. This curious arrangement was due to the scarcity of trained personnel; it was impossible for the constructing company to provide a crew of officers and men capable of handling the ship on trials other than by employing the crew who were to man her when she had been handed over to the Cardington authorities on completion. It will be seen that this position was likely to raise difficulties. The crew of R.100 during flight trials were acting on behalf of the constructing company, but they were employed by the men at Cardington who were both our judges and our competitors. Under such a system difficulties were inevitable, and it is a tribute to the captain of the ship that these difficulties at no time became really serious.
A delay of nearly a month elapsed between the completion of R.100 and her first flight. A flat calm, such as occurs in anticyclones, is required for handling an airship safely in or out of her shed. There was only one mooring mast suitable for these two ships in the British Isles, at Cardington, and R.101 was hanging on it waiting till weather conditions were suitable for her to be taken into her shed. For three weeks R.101 occupied the mast before she could be put into her shed; in the December weather a further week elapsed before conditions became suitable to take R.100 out of the very narrow shed at Howden.
R.100 was as big as an Atlantic liner; she was 709 feet long and 130 feet in diameter, which is to say that she was fifty feet shorter than the old Mauretania but half again as wide in the beam. When loaded for flight she was, of course, as light as a feather and so capable of being swayed by the least puff of wind. So far as I can remember the Howden shed provided no more than two feet clearance each side of the ship as she was manhandled out of the door; she fitted the shed like a cork in a bottle so that we needed a dead calm to get her out. If the airship programme had continued it would have been necessary to devise a mechanical means of controlling the ship to take her in and out of the shed, and we spent many months in 1930 working on such matters, but at that time we were dependent upon manpower and calm weather.
The forecast for December the 16th was satisfactory, a dead calm being predicted for dawn. A party of officials came from Cardington on the previous evening to take part in the first flight, including Major Scott who was in charge of all flying operations of the two ships. I got to the shed at about 3 a.m.; the country roads were choked with motor coaches bringing the handling party of five hundred soldiers to the shed. It was a wonderful, moonlit night, clear and frosty, without a cloud or a breath of wind. We opened the doors of the great shed for the last time, slunk into dark corners to keep clear of the reporters, and stayed waiting for the dawn. In the shed the crew were running their engines slowly to warm up.
The first light of dawn came at last, and at 7.15 we got on board through the control car in the growing light, and the ship was finally ballasted up. Then the order was given to walk the ship aft. A centre line had been painted on the floor and extended out on to the aerodrome and plumb bobs were suspended from the bow and stern; keeping her straight in this way the handling party walked her out. It was
all over very quickly. Inside the ship we could not see when she was clear of the shed, but a great cheer from the crowd told us when the bow had passed out on to the aerodrome.
There was very little to be done. Major Scott had her walked out to a safe distance from the shed, swung her round to point her away from it, and checked the ballasting again. I am told that her enormous silvery bulk was very beautiful in that misty blue December dawn. Scott completed his ballasting arrangements and climbed on board.
The take-off was simple. From the control car Booth emptied a half-ton bag of water ballast from the bow and another one from the stern and, leaning from one of the windows of the car, he shouted, “Let her go.” Inside the ship we heard the cheers and saw the ground receding, and set about our job of finding out our mistakes.
She floated up slowly; at five hundred feet Booth rang the power car telegraphs for two of our six engines to go slow ahead. As the ship gathered way the elevator coxswain nosed her upwards to about a thousand feet and we made a few slow circles over Howden to try out the controls. This was my prime anxiety, of course; the figures had shown that she could easily be steered by hand with these enormous unbalanced rudders, and now was the moment of proof. But I had nothing to worry about; the first turn showed that she was behaving exactly in accordance with the calculations. She was steered by a wheel like a ship’s wheel four feet in diameter. When on a straight course at cruising speed it was impossible to put on more than about three degrees of helm, but that reduction in the effective fin area made her stable on a circle of wide radius and she commenced to turn; as she took up the turn the air flow at the tail was altered and it became possible to put on more helm, so that it took half a minute or more to get her into the condition of turning with full helm upon her minimum turning circle. With this method of control it was impossible to strain the ship by putting on full helm while she was in straight flight because the coxswain was not strong enough, and it proved to be simple and satisfactory.
After a short time we left the vicinity of Howden and flew slowly to York; by the time we got there it was apparent that there was nothing wrong with the ship and we could confidently fly her down to Cardington near Bedford. We circled York Minster and the city, and then, with minds comparatively at ease, we set course for Cardington and went to breakfast.
Breakfast that morning was bacon and eggs cooked on board, the first of many pleasant meals upon that ship. We were all a little elated, and the matter of the parachutes did not appreciably damp our spirits. We had fifty parachutes slung up in various parts of the ship ready for instant use, but there were fifty-four of us on board. We made grim little jokes about the game of musical chairs; after the first few flights the parachutes were removed.
At the same time, throughout the flights of R.100 the action to be taken in the event of disaster was always in the background of my mind, and in view of the eventual disaster to R.101 it is interesting to recall a precaution that I took for my personal safety. In an airship, unlike an aeroplane, there is no great danger of death from violent impact with the ground. Although both ships were filled with hydrogen there was no great danger of fire in the air, for any gas escaping would go upwards and out of the top of the ship, remote from any likely source of ignition. The chief danger, I thought, was of fire after hitting the ground, when broken electrical cables could make sparks in the presence of large masses of escaping hydrogen or petrol; in that case the fire would spread instantly. This, in fact, is what happened to R.101. It seemed to me that in such a case the only chance for survival would be to jump on to the inside of the outer cover and cut one’s way out, and drop down to the ground, and one would have not more than five seconds to do it in. For this reason before the first flight of R.100 I bought a very large clasp knife and sharpened it to a fine point and a razor edge, and I carried this knife unostentatiously in my pocket throughout the flights that the ship made.
We made a quick trip to Cardington by the standards of those days, cruising at about fifty-five miles an hour on four engines only. We made good about seventy miles an hour over the ground with the assistance of a following wind, and reached Cardington in two hours’ flight from York. Here a surprise awaited us; we had assumed that there would be little difficulty in landing the ship on to the Air Ministry mooring mast. So many articles had appeared in the press about the wonders of this new method of handling airships that it came as a surprise to us to find that the experts on this matter were inexpert in the use of their rather complicated apparatus. On this first flight it took three hours to land R.100 to the mast; three times we had to leave the aerodrome and fly a circuit and come in again, and make a fresh attempt to establish the connection between the steel cable dropped from the nose of the ship and the cable from the masthead laid out upon the aerodrome. The mooring system was essentially sound and at the conclusion of the R.100 flights sufficient experience had been gained in the handling of the ship and in the use of the mast equipment to enable a landing to be made to the mast in about forty minutes, but this result was not achieved without the experience of numerous mistakes. And here we touched the fringe of one of the chief dangers of the airship programme; too many experiments were being made at the same time.
We landed at about three in the afternoon. That evening we held a conference and decided to fly again next day, taking advantage of the calm, frosty weather. There were several minor defects to be made good upon the ship during the night. One engine had a leaky cylinder and another was suspected of having run a big end; air was eddying in violently at cruising speed through one of the big outer cover ventilators and blowing the gasbags about; this had to be sealed up. A dynamo engine could not be turned over with the starting handle. We held our gloomy inquest on it in the middle of the night, only to discover after two hours’ work that the starting handle itself was seized solid in its bearings and the engine was in perfect order. These were the inevitable teething troubles of any very large aircraft, but they meant much work.
I got back to the ship that night at about nine o’clock. It was a cloudless, moonlit night, and freezing hard. The ship lay at the mast a hundred feet above the ground, brilliant silver in the beams of the floodlights. There was a crew on board her in accordance with the routine procedure at the mast; I found them at supper in their mess, content and settling in to their new quarters. There was no heating in the ship when the dynamo engines were stopped, and it was very cold. In the control car I found Booth, dead tired, wearing a Sidcot suit and huddled in a small armchair beside the shore telephone, nursing the ship’s black kitten as he kept his watch in the brilliance of the floodlights. I went on aft to the power cars, and worked till midnight with the engineers.
We flew again next day with the intention of doing speed trials. The speed of R.100 at that time was a sore point at Cardington; with all politeness the officials there professed themselves unable to believe our ship to be at least ten miles an hour faster than their own. R.100 was, in fact, the fastest airship that had ever flown at that time, or to this day, for all I know; her full speed was eighty-one miles an hour. We did not reach full speed upon that flight, however. Prowling through the ship in search of trouble somewhere over Kettering I heard a little flapping noise of fabric in the region of the lower rudder, and dis. covered that a sealing strip across the rudder hinge was coming unstuck. This was not serious, but we did not care to take the ship up to full speed till it had received attention in the shed; we cruised around for a few hours and landed to the mast again in the middle of the afternoon.
The landing on this occasion was a demonstration of the special qualities of the airship. A thin, frosty mist hung over everything; from seven or eight hundred feet it was just possible to distinguish the ground immediately below. In these days every modern aid would be required on such an afternoon to guide an aeroplane on to the runway; in those days flying would have been most hazardous. In the airship everything was peaceful and secure. We had radio telephone communication with the mast, and comin
g up to the aerodrome we slowed to a mere crawl, running on one engine at about ten miles an hour with two other engines ticking over slow astern ready to check her way if anything loomed up ahead of us. In the control car there was time for a little conference between the officers over each movement of the controls, as, “Putting her nose down a bit, isn’t she?” “Think so? We could afford to be fifty feet lower.” “Starting to show on the fore and aft level, sir—about two degrees nose down.” “All right. Coxswain, five degrees elevator up.” And so on. During all the flights that R.100 made I do not think that it was ever necessary to make a quick decision in the way that the pilot of an aeroplane has to; there was always time to talk the matter over if it seemed desirable and decide what action should be taken next. It is impossible to describe what a sense of security this freedom from quick decisions gave to one who was accustomed to fly aeroplanes; rightly or wrongly I felt as safe through all the flights that R.100 made as on a large ship.
We put the ship into the shed that evening, ‘put her back in the box’ as somebody irreverently described the operation. Here she stayed over Christmas while we sorted out her teething troubles, berthed in her shed beside R.101. Some of us had seen R.101 before she flew; we now had a good opportunity to examine her in her completed state. We found her an amazing piece of work. The finish and the workmanship struck us as extraordinarily good, far better than that of our own ship. The design seemed to us almost unbelievably complicated; she seemed to be a ship in which imagination had run riot regardless of the virtue of simplicity and utterly regardless of expense. The servo motors were there, large as life and every bit as heavy. The gas valves were of a novel design and reported to be very sensitive; being located on the side of the bags a small degree of rolling would cause them to open and lose gas. Airships, however, don’t roll very much. The feature of the design that perturbed me most of all was the method of taking the thrust of the engines in the power cars to the hull. The engine in each car drove a pusher propeller. A large thrust bearing was mounted in the boss of this propeller, from which a heavy steel cable ran straight aft to a point on the hull fifty feet back. It was fairly common practice in the airship world to take the thrust through a propeller in that way and in fact it gave no trouble, but it seemed to me most dangerous and quite unnecessary. A competent engineer should be able to do better than that.