BRITISH FLYING NEWS

Hokitika Guardian, 20 June 1931, Page 6

BRITISH FLYING NEWS

A REMARKABLE INVENTION. ZEST OF THE PRINCE OF WALES. LONDON, May 1. No feature of the Prince of 1 Wales’ great tour of Latin America and of h.s activities at Buenos Aires has attracted more attention than his enthusiasm for aviation, and the extensive, and nonchalant use he made in Argentina of his own light monoplane, taken to South America at his express desire in the aircraft carrier Eagle. He Hew far and long, frequently in the pilot’s seat; he paid many visits in the Argentine provinces. taking his friends for flights with him and preaching always, by example and precept, the gospel ot flying- No man has done so much tor the development of aviation in South America. A wave of interest has swept the peoples of the great countries which make up the continent, and suddenly Hying has received an impetus sufficient to effect quickly the result's expected from years of less brilliant effort.

The Prince’s private machine, attended by 'Mr Fielden, his personal pilot, made a number of preliminary flights over the Argentine provinces where' the Prince wished to visit,'to survey the ground and locate the best landing places. Some idea of the amount of ground which the flying machine is able to cover in (i short time may be gained from the fact that in one day, during which he spent 94 hours in the air, Mr Fielden travelled’ between 1000 and 1100 miles, at _an average speed of 112 miles an hour.

AIRSCREWS OF VARIABLE PUT Japan and Soviet Russia are among the Powers which have recently acquired 'British variable pitch airscrews, built on the Hele-Shaw principle, from the G!oster Aircraft Company. This remarkable invention is the most successful materialisation yet achieved of an idea pursued by engineers for many years, and ranking with the wing of variable camber and area as a development which from time to time is confidently expected to have incalculable effects on the future of aviation.

The normal airscrew has fixed blades and is most efficient during one phase only of the flying done by the aircraft to which it /is fitted. Thus, a screw designed for high speed may he inefficient while the aeroplane, climbs and make take-off difficult; con verst ly, a good climbing screw may affect the maximum speed of the machine. ’Compromise is one answer, as in many other problems of aircraft design. The designer fits the airscrew which gives best all-round results in the living the particular aeroplane is intended to do; aeroplaiv s built for special work, the racing seaplanes constructed for the Schno'der Trophy contests, for example, will naturally be equipped with airscrews more efficient at speed than in oth°r ways. The choice of the right airscrew is most important, and, on the basis of present knowledge, often exceedingly difficult. It is one of th° key problems facing the builders of the Schneider Trophy racers this year.

HYDRAULIC GEAR. Obviously the performance of any aircraft could be improved by an airscrew so constructed that the blades, moving automatically in flight under the carrying loads imposed on them, should al-, ways take up the angle of pitch best suited to the flying state of the aeroplane, whether it were moving forward at full throttle in level flight, climbing, taking-off, or diving. The Hele-Shaw gear, working on hydraulic principles, is embodied in the hub of the airscrew, and goes a long way to meet the demands of the a'icraft designer. The earlier models of the gear were complicated ,a.nd heavy, but steady development has brought (low n the weight and considerably simplified the mechanism. Severe . endurance trials have failed to reveal any weakness of design, and the Glostev Company are. now working on the construction of hollow steel airscrew blades which may still further reduce the weight of the airscrew unit.

In actual flight the gear has completed about 50 hours' flying with a Bristol “Jupiter” air-cooled radial engine. Further trials are plann J with IRolls-Royce and Armstrong-Sidd-ley motors.

HEAVY OIL ENGINES

Leading ißritish aero enerin° build'-vs have spent much time and money recently on a study of the problems involved in building compression-ignition engines burning heavy oil instead of petrol. The engines fitted to the airship RICH belonged to this category of power plant but their excessive weight prevented their use in heavier-thah-aiv flying machines. The advantages, of using compression ignition motors—increased range because Kss weight of fuel is consumed, economy simplification because an electrical ignition system is not required. and freedom from fire risks—are sufficiently attractive to make experiments worth while. The , greatest difficult-.' is to reduce the weight of the engin<\ but recent development has succeed d n reducing the weight to a reasonable figure, and a British aeroplane fitted w'th a heavy oil motor is expect'd to take he air during the summer. In' accordance with nnirnrl ir Ministry procedure, research work <>n tlrs subject is secret, but it is possible to state that the British e'-normerts have produced a motor n.t least Ahe equal in efficiency of am- constructed abroad. Air experts will watch its future with keen interest.