3 SEPTEMBER 1954, Page 21


The Signs of the Air Show

BY OLIVER STEWART VALUATION' is the American term : the Americans ' evaluate' new aircraft and new engines, they do not assess their merits, and in this as in other things, British aviation is tending to go the American way. The Society of British Aircraft Constructors' Display and Exhibi- tion at Farnborough is an ideal opportunity for evaluation; for setting our own aeroplanes and engines in qualitative relationship with those of the rest of the world. Quiet technical interest marks this year's programme, with few startling novel- ties and no ' sensations ' such as the Saunders-Roe Princess flying-boat created last year. Attention focuses first upon a development which, in my view, is of supreme technical, tactical, logistical and constructional importance, the light- weight or screened fighter represented by the Folland Midge. W. E. W. Petter, who designed the Canberra bomber, is one of those bright young men who can not only produce brilliant ideas, but who can also see them through to fruition. Three and a quarter years ago he decided that fighter aircraft were becoming much too heavy and much too complicated for effective use in battle. He had plenty Of evidence from the Second World War and from experiences in Korea to support his view. He pointed out that for every pound weight of additional equipment put into a fighter, the all-up weight of the machine as ready to fly went up ten pounds. He pointed to the appalling constructional, servicing and mdintenance difficulties associated with the conventional heavy, complicated fighter. But he recognised from the start that there could be no compromise on air performance, without which the aircraft Would be ineffective in battle, and that there could be no com- promise in pilot services. The pilot, must have a pressure cabin with air conditioning and he must have an ejection seat.

From this starting point he set himself to design a fighter. The Midge is the first result. It flew on August 11 piloted by Squadron Leader Tennant. On its third flight it was doing rolls and tight turns. Soon after it had attained a speed of Mach 0.95. Its promise was established. But the engine of the Midge is an Armstrong Siddeley Viper of 1,640 lb. thrust, Which is smaller than the aircraft is intended to take. It will take the Bristol Orpheus of about three times the thrust and with this it will out-climb most if not all conventional fighters; It will be supersonic in straight and level flight; it will have an endurance of over one hour and it will outmanoeuvre any other fighter in existence. With the Orpheus it will be called the Gnat. Only in armament will it be less powerful than conventional fighters. for it will carry two of the new Aden 30 mm guns in place of four. For all countries near a battle area, the argument in favour of the screened fighter represented by the Midge or Gnat is overwhelming. A Gnat takes one fifth the man-hours to build, costs about one third, requires about one half the tooling and about one half the man-hours for servicing and main- tenance of a conventional fighter. There are a thousand other Points in its favour; but they must be left unrehearsed here. The Folland Gnat is a military portent of supreme interest.

Curiously enough the new conventional supersonic fighter, the English Electric PI, originated when Petter was still with the English Electric Company. But it has been developed Under the direction of another young and brilliant designer, FI.W. Page. It has something like ten times the thrust of the Midge and it is said to have exceeded the speed of sound in straight and level flight, though in what temperatures is not Mown. At the time of writing there is uncertainty about Whether the PI will be seen at Farnborough. An official statement said that it would not appear, but later reports were !0 the effect that it might make a fly-past during the display. It has marked swept back wings and two Armstrong Siddeley Sapphire engines mounted one above the other. 110 and the Vickers Supermarine 525, twin-engined, naval fighters, and the latest marks of Hunter and of Swift single- engined fighters. Among the larger military machines there is nothing new, for the Victor, the Valiant and the delta Avro. Vulcan have appeared at previous displays. In the large-size civil aircraft there is the Comet III, representing the third phase, of Comet development, and bigger than the Comet II which is also to be shown. The Comet III is a fine aircraft; but while the report on the accidents to the Comet I is awaited, it cannot produce its full effect. The Bristol Britannia turboprop air . liner, upon which a great national responsibility now rests, will be shown on the day devoted to civil aircraft, Thursday, but not on the other days. The Vickers Viscount, for which type 153 firm orders have now been placed, should make an appearance, but its place in the programme has not been settled: early enough to say whether it will appear on the civil aircraft day or on the other days.

The smaller civil aircraft are much the same as usual. They include the remarkable Scottish Aviation Prestwick Pioneer, the de Havilland Heron, the de Havilland Beaver and the Saunders-Roe and Bristol helicopters. Naval aircraft, in their specialised anti-submarine form, are represented by two aircraft which exhibit highly individual and original thinking, the Short Seamew, simple, rugged, single-engined, anti-sub- marine aircraft and the more complicated Fairey Gannet double-engined dual role search and strike anti-submarine aircraft. Trainers are to be shown by Boulton Paul and by Hunting Percival. The last named company will have its new jet driven trainer the P-84 or Jet Provost in the flying display.

In the engine field the company of Rolls-Royce will demonstrate the truth of the opinion expressed to me by the chief engineer of another -firm, that it sets a cracking pace' in engine development which all other companies in the world find it hard to follow. The new Rolls-Royce Soar, a small size turbojet engine, is as near to an engineering miracle as has happened for some time. It gives a greater thrust to the unit weight, a greater thrust to the unit frontal area, a greater thrust to unit size than any other gas turbine in existence. Its specific weight, indeed, at less than 0.15 kilograms weight to the kilogram thrust is positively amazing and a revelation of the distance the Derby designers and development engineers have gone in improving the efficiency of axial flow compressors and of gas turbines in general. The Soar engines are perhaps the greatest engineering achievement represented at the entire Farnborough show this year. - Among other engines seen for the first time at Farnborough will be the Napier Eland turboprop and the very small Blackburn Turbomeca Palas turbojets. The Palas engines are being built under licence from the French Turbomeca company by Blackburn and should prove extremely useful. They will be seen in an important research aircraft, the Short Sherpa.

The Short Sherpa is fitted with isoclinic wings, a novel type of wing developed from an idea which Professor Geoffrey Hill originated. Professor Hill, the brother of that fine pilot Sir Roderic Hill, has an original mind and has always been striving to improve aircraft performance in all speed ranges since the days when he and his brother built and flew their first glider. That was well before the First World War. Hill has been responsible for the long line of tail-less aircraft known as the Pterodactyls. In his new wing the idea is to arrange the structure so that the wing bends as it twists and maintains a constant angle of attack throughout its length.

If one seeks to sum up the promise of this year's Farnborough display, one might say that it will not be so sensational as past displays, that it will not offer any remarkable aircraft achieve- Ments; but that it will suggest new thoughts in many fields. The screened or light-weight fighter, the small but powerful jet engine and the aero-isoclinic wing are indications that 'strongly individual designers and engineers are not lacking in the British aircraft industry.