Observers conditioned to the routine pattern of carrier operations must concede that things are not at all what they seem to be in the sequence of photographs on the facing page. For, when properly viewed from bottom to top, they depict, not a standard approach and landing, but record a highly unusual launch and departure—backwards—of a glider. But don’t take our word for it—read on.
At 10:30 on the morning of 29 May 1945, I was airborne in a two-seater glider about 300 feet over the waters of the Irish Sea, about ten miles off the northeast coast of the Isle of Man. Since it may strike the reader that this was a somewhat unusual place to be flying a motorless aircraft, I hasten to explain that I was being towed by the aircraft carrier HMS Pretoria Castle on the first of a series of experimental flights in a program of investigation into the behavior of the air wake behind such vessels.
I was attached to the Pretoria Castle by about 1,000 feet of cable from a winch situated on the forward end of the flight deck, and from my windy vantage point she looked quite small and not very obviously part of the act. The Pretoria Castle, a converted Union Castle liner, was not a particularly speedy carrier as carriers go, and at this particular moment in time the ship was steaming flat out into a light southerly breeze and only giving me a margin of some four or five knots above the air speed at which a stately descent into the sea would take place. This was not a state of affairs conducive to a feeling of security, but nevertheless, as the air was smooth, and the glider controlled remarkably well considering the circumstances, one could not fail to be impressed by the novelty of the situation. It was a heady feeling to reflect that flying an unpowered flying machine from an aircraft carrier had almost certainly never been done before anywhere in the world, and, owing to the expense and general palaver, was unlikely to catch on as a popular pastime.
True, the famous American-turned-English flying pioneer, Colonel Cody, had done much the same sort of thing in 1900, whilst slung beneath a team of his man-carrying kites, and towed by the destroyer HMS Grafton. But, on that occasion, the gallant Colonel had ended up in the drink, Stetson hat and all, as the ship turned downwind for reasons which are unclear.
So, here I was some 45 years later, on similar airy passage, behind one of HM ships in search of scientific truth—hopeful that there would be no encore of Colonel Cody’s soggy performance.
My precarious perch at the end of the long thin wire came about because, towards the end of World War II, the Royal Navy had a substantial number of aircraft carriers in commission, and a great deal of carrier flying was taking place. Inevitably, there were many deck-landing accidents and incidents in which the current Fleet Air Arm aircraft such as the Seafire, Grumman Hellcat, and Barracuda were being ditched. In the responsible departments of the Admiralty, there was preoccupation with the accident reports and the statistics thereof. Many of the accidents were being attributed to turbulence aft of the ship, which was particularly disquieting since, for some time past, ship model tests carried out in the large open-jet wind tunnels at Teddington’s National Physical Laboratory, had given this aspect of carrier operations a clean bill of health. “Turbulence minimized” was the way the scientific civilians, or “boffins” graded the carriers on the basis of the model tests. Still, something was obviously amiss and the boffins, too, began to suspect from the “sudden gust” statistics, that there was something phony about their model test results. Thus, minds were turned to finding a way of checking up on what actually went on up there behind an aircraft carrier.
After discarding all sorts of ideas from streaming smoke to towing balloons, someone hit on the idea of towing a full-sized glider from a carrier and getting the pilot to explore the whole of the airspace behind the ship in a methodical manner. The glider would be equipped with recording instruments which would indicate roll and pitch with great accuracy and, provided the glider could be maintained at fixed levels, the up trends and down trends in the ship’s air wake could be deduced. Accordingly, the call went out from the Admiralty for someone who “knew about gliders” to find a suitable machine and perform as its pilot.
In due course and by devious ways, the light shone on me as a Fleet Air Arm aeroplane driver with glider experience, and I was asked if I would do the job. Preoccupied as I was at the time with avoiding what sounded like a most uninteresting appointment to some obscure outpost in India, I accepted with gratitude and a feeling that, at the most, one could only get wet—and it might even be useful. So, when the deal was all set up with the Admiralty department sponsoring the project, I was let loose to look around for a likely glider. The most obvious first place to investigate was my prewar bailiwick of Kirbymoorside in Yorkshire, where I installed myself in one of the pubs to take stock of what was available at the nearby glider building firm of Slingsby Sailplanes. I knew the firm very well as I had worked for them before the war as a designer of gliders and general factotum.
It appeared that I had arrived at a good time for all concerned as Slingsby’s happened to have a prototype tandem two-seater training glider called Type 20, which was surplus to requirements; and when I tried out the machine on several soaring flights over the range of hills not far from the factory, it seemed to be an ideal aircraft for our job.
The Type 20 was quite lightly built and had a span of about 50 feet. There was an adequate rear cockpit under the wing—ideal for the instrumentation—and the ailerons were quite powerful throughout the whole speed range. Because I envisaged fairly marginal relative wind speeds when we would fly from the carrier nominated for our experiments, I immediately began to design the biggest pair of button-on fixed flaps that the wing of the T.20 could accommodate. My reasoning was that maximum lift was all-important regardless of drag—and with the unprecedented horsepower of a ship available to pull—the more drag the better, in order to keep the tow cable taut. So the flaps were made adjustable on the ground to give a selection of settings from about 10° to 45° in order to find the best setting for minimum airborne speed compatible with controllability.
To establish the above characteristics, a series of car towing tests were carried out on the runways at a nearby R.A.F. airfield, and we eventually fixed a flap setting of about 30° which gave a minimum “sustained flight under control” speed of 22 m.p.h. Naturally, the ailerons were none too effective at this speed. But, after we had added about two inches to the trailing edges, control was about adequate. At first, we towed the glider out to the starting point each day with the usual 10 feet of rope and with someone walking at the wing tip. I very soon discovered that if the tow car went just a little faster, the glider, with its enormous flaps, would become airborne in the ground effect at little more than running pace. So, from then on, we “flew” the machine everywhere about two feet high on the end of the 10-foot rope—a trick which seemed to amuse the R.A.F.
When the glider was about as good as I could get it and the scientists from the Admiralty Research Laboratories at Teddington had designed and installed their pack of instruments in the rear cockpit, the time came when we were given a slot in the program of the trials carrier of the time, HMS Pretoria Castle. The ship was based at Tail of the Bank on the Clyde in Scotland, and one rainy and blustery day I found myself climbing the 30 feet or so of rope ladder up to the vessel’s boom. The glider and the scientific party were already on board ready to go, and that evening a crowd of ribald spectators assembled in the hangar to watch the rigging and other preparations. The Pretoria Castle was a most comfortable and hospitable ship, her crew well used to unorthodoxy and the sometimes rather weird civilians of the genus boffin. But the glider was something which even the Pretoria Castle people had not seen before, and that evening before dinner in the Wardroom, there was much swapping of turns of duty among the below-decks ship drivers so as to be topside when the day came to be able to see the glider perform—and, with luck, go over the side! Needless to say, I looked forward to such a possibility with gloom, but as a tot of gin was preposterously cheap and the supply ample, I managed to maintain some sort of front amid the general hilarity.
In what seemed like no time at all, the carrier sailed down the Clyde for the open sea and, on the morning of 29 May, I found myself strapped in the front cockpit of the T.20 complete with my Mae West, the winch wire connected up and the ship turning into the wind entirely for my benefit. The sightseeing part of the carrier island was black with spectators, all laying bets of various kinds and eager to see the dunking.
The T.20, positioned about 60 feet forward of the round down, had been equipped with a walkie-talkie type radio and rope pennants on each wing tip. I had attached a loop of rope on the center section to hold onto if the worse came to the worst! Deck handlers were stationed on each of the tip ropes and at the nose to keep the machine steady until I gave the word go.
When the ship was on course into the wind and with 35 m.p.h. on my air speed indicator, I got the green flag from the batsman and no sooner had I given the word than I was airborne. My Elisha-like vertical ascent was surprisingly easy as I eased back against the tow cable and I let the glider ride at about 50 feet above the deck. The glider controlled in normal fashion, so after a while I used the lift spoilers to jockey my way down to the deck of the ship again, where the handlers were waiting to grab me. All had worked well, and I repeated the performance three or four times to let everyone, including myself, get the hang of things and once more at 50 feet above the deck, I called upon the winch driver to pay out the cable.
It was a funny sensation to see the ship gradually shrink as I continued my stern-first climb, and when I was about a ship’s length astern and about 250 feet above the sea, I called for the cable to be stopped. All was smooth in the cheese-like air well above the ship, and I found I was able to fly well out to either side and climb and descend more or less at will. At first I was not too keen to descend too low into the area where the worst air turbulence might be expected, but cautious exploration did not reveal anything of any great significance. I was just about to descend once again to see what would happen, when I noticed that the wind noise was decreasing and my ASI had begun to show a dangerous lack of knots—I was on my way down whether I liked it or not!
I immediately called on the radio for more speed—only to be told that the ship was going full out—and that the reason for the general slackening off of things was that we had steamed into a lull in the natural wind. I therefore called upon the winch operator, a civilian gliding friend of mine, one Sam Youles, to “pu-u-u-ull,” with various unquotable embellishments to lend emphasis. There being no immediate response to what I thought were quite reasonable requests, I continued to flute appeals to Sam to give me forward movement at all costs, as by this time I was beginning to well and truly subside. The descent continued but, just when I had resigned myself to the Irish Sea, there was an almighty jerk on the cable and I zoomed back in seconds from 40 feet to the comparative safety of 200 feet. It was a close call indeed, and why the cable did not break or pull the nose off the glider, I still do not know.
Somewhat shaken, I called up to say I was coming in, and the winch continued to haul me in to a running landing, aided by some nifty work with the spoilers. As our allotted time for the preliminary tests was up, the T.20 was taken down on the lift to the hangar, and our first session was over. Needless to say, there were a few words I wanted to exchange with my friend, Sam Youles, over the contretemps with the winch. All, or nearly all, was forgiven when he explained that, at the moment of crisis, the winch engine had stalled on him. The resourceful deck landing control officer was just organizing a pulley-hauley party of deck handlers to pull me in manually, when Sam got the winch going again and in the general excitement he had been a bit heavy on the throttle. All I could report to the scientific party regarding the behavior of the glider in the ship’s airwake, was that nothing untoward had been encountered and at no time had any extreme control movements been necessary. The recording instruments had, of course, been working all the time I was flying, so no doubt these would tell all—or so it was hoped.
The Pretoria Castle proceeded with the remaining program of trials and when we returned to the Clyde all our gear was taken ashore. After a little time it appeared that the boffins were very dissatisfied with their instrumentation, and a new outfit would have to be designed. After several months, in which time I was employed on various other things, including learning to fly Sikorsky R-4 helicopters, a new and much more elaborate instrument pack was produced and fitted up for more land-towing trials at the R.A.F. airfield in the north of England. Again the apparatus did not satisfy the scientists, and, what with one thing and another, some considerable time elapsed before we again took the T.20 to sea, this time in HMS Illustrious. The performance was much the same as before and I made several quite long flights in various areas without incident. Due, I suppose, to my keen sense of self-preservation, I managed to get back to the safety of the deck each time.
On this series of trials it had been decided that I should introduce another pilot to the rather unusual art of ship-towed gliding, so I had selected a fellow naval officer to be my stand-in and general assistant. He was a skilled deck-landing pilot with a fair amount of glider flying experience. When I had completed my flights, after an exhaustive briefing my chum was strapped into the cockpit of the T.20 and the Illustrious was once again turned into the wind. On the word “go” the glider was released in the normal manner, but this time, instead of pulling back on the stick and getting well clear of the deck as had been carefully explained, my friend continued to fly about three or four feet above the deck in a zero incidence condition. In this unsatisfactory situation he allowed the T.20 to begin to weave to left and right until for some reason which I still do not understand, he weaved right across over the starboard side of the flight deck, still only about ten feet above the take-off level. Disaster was obviously at hand and it was not long in coming.
The tow cable became irretrievably tangled in one of the radio masts, which on HMS Illustrious were lowered to horizontal position during flying operations—and the T.20 was doomed. The glider sank out of sight below deck level, scraping the port wing down the side of the ship as it went, and when it re-appeared under the stern of the Illustrious, it was floating like a duck on the turbulent water. My would-be apprentice must have been very nippy indeed, as by the time we saw him he was firmly installed on the center-section of the glider holding onto the loop of rope I had so thoughtfully incorporated for that very purpose.
Away went the T.20, far astern, and in a short time we were relieved to see its occupant being rescued by the escorting destroyer. But what to do about the T.20, which appeared to have most seaworthy qualities? In the end it was decided that the destroyer disperse the remains on the surface of the ocean by ramming it repeatedly at high speed.
A sorry end it was to a good machine. Still, I think that the demise of the T.20 was not too unwelcome to anyone, coming in the way it did. The experiment had dragged on for a very long time in an inconclusive manner, as these things sometimes do, and the ditching of the principal piece of equipment was a good excuse to have another think. So, in the end, the Admiralty scientific team decided to do some experiments in ship-wake investigation with helicopters, which by this time, in 1949, were becoming a normal part of the Fleet Air Arm inventory. And these vehicles had the advantage of being a lot easier to stage-manage on a busy trials carrier than all the paraphernalia and carry on which went with the glider towing activity. In my case, I was not sorry to see the experiment called to a halt because by now I had become well involved in the new and fascinating helicopter business, so obviously suited to a multitude of naval uses. I had felt for some time, moreover, that while ship towing of a glider from a carrier was not in itself all that difficult, it was doubtful if anything of significance could ever be gleaned from it for this particular purpose. And, in any case, by this time there were signs that deck-landing accidents could be reduced by better training and various technical improvements—the path which led in due course to the introduction by the Royal Navy of the angled deck and mirror landing sight.
So, while I was sad to see the end of the excellent T.20 glider in which I had always succeeded in keeping my feet dry, for me its watery end was a release into very rewarding Fleet Air Arm affairs with helicopters, a world in which I remained until I retired from the Service in 1960, and in which I am still involved.
The ship gliding experiment may not have contributed a great deal to the advancement of carrier flying, but it was an interesting experience. Somewhere there may be another aging and slightly rotund ex-naval pilot who has, perhaps, flown a slow aeroplane off a carrier deck into a strong wind—and departed backwards. But I am pretty sure that I can claim the dubious distinction of being the only one who has ever done it in a glider.
Commander Sproule began flying gliders in 1929 at the age of 14 and, in 1940, entered the Royal Naval Volunteer Reserve for flying duties in the Fleet Air Arm. In 1941, he was transferred to the Royal Air Force to assist in setting up the wartime troop-carrying glider organization. During World War II, he served for a short time at the Philadelphia Navy Yard participating in “Project George,” which involved experimental flying in connection with the development of towed gliding bombs. Commander Sproule was permanently commissioned in 1945 and became one of Royal Navy’s pioneer helicopter pilots, learning to fly the Sikorsky R-4 type. During his service career, Commander Sproule took part in many helicopter rescue missions off the U.K. coasts and devised several items of equipment that were accepted for service use. Notable among these being the “Sproule” helicopter rescue net and the harpoon-grid helicopter arresting gear. He retired from the Royal Navy in 1960 and now manages the London office of Agusta, the well-known Italian helicopter building firm.