The Aeroplane Of To-morrow-How Fast And How Far?

Auckland Star, Volume LXXII, Issue 281, 27 November 1941, Page 6

The Aeroplane Of To-morrow-How Fast And How Far?

What will the aeroplane of to-morrow be like? This week the Clipper left Auckland carrying about fifty passengers and a crew of 12. Will such a plane and such a load be thought very small in a few years' time. It seems likely to anyone reading Noel PembertonBilling's latest book,* which is not an essay in daring prophecy, but a closely argued, semi-technical discussion of what its author thinks to be not only possible but probable in aviation in the near future.

The book contains a sketch design for a flying boat to cross the Atlantic with a crew of 20, equipment and furnishings, 500 passengers and their personal luggage. It would also carry other luggage, mails and freight, which would be dropped by parachutes. On such a journey, the author calculates, an average fare of £30 per passenger should show a large profit. The trip would take eight or nine hour.!. Take-off Difficulties What difficulties stand in the way of such a development? At present, the author explains, "the normal aeroplane can never approach its full efficiency at high speed because it has had to be designed for taking off." If no one had ever thought of variable speed gearboxes for road vehicles, so that a motor ear had only one gear ratio, then it would have been necessary to make that a very low gear, so that it could start satisfactorily and climb steep hills; but for level running it would have been very inefficient, and the top speed would have been seriously limited Thus, before an aeroplane can become as efficient as a motor car it must have a way of varying its wing area so that it can take off and climb with low wing loading and then, when it has reached its operating height, be able to reduce its wing area and proceed at full speed with small, highly loaded I wing.

Before this becomes possible some fundamental changes in aeroplane design will be needed, and Mr. Pemberton-Billing discusses the nature of these and puts forward his own proposed solution of the problem. In the past, he points out, improvements in engines, materials, aerodynamics and wing loading have made better aeroplanes. The engine designer, he thinks, cannot be counted on to supply any further great increases in speed, and improvements in materials and in aerodynamics also appear to be approaching their limits. The greatest amount of room for development is in wing loading. "If ever civil aviation is to play an important part in long-distance transport, and If the bomber is to become a truly devastating weapon of war, then ways must be found of carrying far greater loads than are carried to-day. But "greater loads and range cannot be obtained merely by increasing size'. The only manner in which they can be obtained is by increasing the wing loading—i.e., putting more load into the same size of aeroplane rather than building a bigger aeroplane for the bigger load."

The author's main contention is that aeroplanes can carry very large loads only* if their take-off is assisted. He examines several. proposals for lessening the difficulty of getting a heavily loaded plane into the air, including the improvement of flying fields. The latter is enormously costly. Mr. PembertonBilling quotes an estimate that there would be needed a ground of "not less than two or two and a half miles diameter" (about 3000 acres), every square foot of which would need "a surface equal to that of a first-class highway." Estimated cost, £2,000,000. He concludes that there is no practicable alternative to assisted take-off. Assisting the Take-off As is well known, assisted take-off is not new. A warship's planes are assisted by a catapult, as were also the mail-delivery planes carried by some Atlantic liners. The Mayo Composite aircraft was designed to solve the problem. Refuelling in the air reduces the take-off weight by adding to the load after the aircraft is in the air. There have been experiments with rockets. In the Mayo Composite the heavily loaded plane is loaded on the back of a large machine, so that the two form a "temporary biplane." The experiment, despite its apparent success, has been criticised on the ground that it does not show a real advantage commensurate with its cost and complication. Mr. Pember-ton-Billing's conclusion is that despite its historic interest it must be regarded as an aeroplane of yesterday, with no future. The real solution of the problem, he contends, is to add an extra wing for the takeoff, and then "slip" it.

The "slip-wing" would consist of a glider containing a pilot, though it might have a light engine. The author claims for the expedient simplicity, low cost, adaptability, extreme mobility, and a number of other advantages. He says that a P.-B. composite, now under construction, is designed as a small naval dive-bomber to carry twice the load now carried by existing types, for twice the distance, on little more than one-third the power. He believes that its most valuable application in the future may be to the big transocean flying boat. Faster Bombers How all this will work out in practice no layman can pretend to know; but it may be worthwhile to outline some of the author's arguments for the application of a slip-wing, principle to bombing planes. As the enemy's fighters become faster, the bomber's armament must be made heavier—or, as he contends, the bomber must be reduced in size, so that it, too, becomes faster. He says that "figures have been worked out" (presumably by himself) for a bomber with a crew of one, which could carry 20001b of explosive for 2000 miles at 500 miles an hour. Such planes would be "invaluable for the destruction in daylight of highly-important targets, such as the bridge in France that cost 37 medium bombers." He insists that it is possible, by the use of the slip-wing, to build general purpose bombers to carry 10,0001b of bombs for 5000 miles at a cruising speed of 400 m.p.h.

The particular proposals made by the author are for examination by experts. The fascination of his book lies in his lucid explanation of a great variety of the problems and difficulties associated with aviation, and the progress made to date in overcoming them. Its author has always been uncommonly fertile of ideas. One of them, expressed as long ago as 1916, was that he would live to see aeroplanes fly at 500 m.p.h. That was ridiculed then, but no one would ridicule it now.

•"The Aeroplane of To-morrow." By Noel Pemberton-Billing CRobert Hale, Ltd.).