Viewing page 84 of 125

This transcription has been completed. Contact us with corrections.

November, 1931   U. S. AIR SERVICES


Power and Speed

The Influence of the Schneider Contests


  Aviation events at home and abroad during the past few months have served again to point out the fundamental importance of engine development in the never ending effort toward higher speed. The performance of various engines which powered the airplanes in the Bendix derby and the Thompson trophy races was particularly meritorious, and, in the view of the fact that the machines which places second and third respectively in the transcontinental race were stock transport planes with stock engines, it is evident that the traveling public is now in position to profit by the engine and aerodynamic developments of the recent years. The particular transport planes referred to were Lockheed Orions, one of which averaged more than 199 miles an hour from Los Angeles to Cleveland. Hitherto such speed in long distance flights has been confined to pure racing types of aircraft whose speed was not a useful commodity, in the accepted sense, but now one can step aboard a transport airplane in Washington and step out of it in Newark, N. J., sixty-eight minutes later. This is useful speed which to a great extent, will compensate for the time lost in going from hotels to airports, and so on. 
  This progress is indeed gratifying and is a compliment to the engineers who have made such transport needs possible. However, we cannot stop at this point and exult too long on our development of fast transport aircraft and rugged engines while various European nations leave us far behind in technical developments which have resulted in high speeds almost beyond one's imagination.
  On September 13 at Calshot, England, a British racing seaplane was flown over the 218-mile Schneider Cup race course at an average speed of 340.6 miles an hour. The same day another similar seaplane was flown several times over the three kilometer sped course for a new world's high speed record of 379.05 miles an hour. A few days later, after a special engine had been installed in the racer, it was again flown over the speed course and this time the record went up to 408.8 miles an hour. To realize the real significance of this speed we should remember that the American speed record is a fraction over 257 miles an hour. The British racer was fitted with a giant engine which is said to develop about 2,500 h.., while the American record was established by the air-cooled engine of about 500 h.p.

  IT IS thus evident that engine power has become a primary factor in boosting the speed marker high and higher. However, that isn't all, for the aerodynamic and structural developments must keep step with the improved power plants. For example, in 1914 a British seaplane won the Schneider Cup race at 86 miles an hour with an engine of 100 h.p. On this basis and assuming that the power required varies at the cube of the speed, the 1931 racer would have required an engine of more than 6,000 h.p. to enable it to make 390 miles an hour.
  Prior to 1925 the engines in the various Schneider Cup entries had gradually increased in power until the 1925 American racer flown to victory by Jimmie Doolittle made 232.6 miles an hour with a 1,400 cubic inch engine developing about 600 h.p. The following year (1926) the Italian government sent over some very fine Macchi monoplanes with 800 h.p. Fiat engines and lifted the cup with relative ease at a speed of 246.4 miles an hour.
  From then on England and Italy become engaged in a titanic struggle for speed supremacy. France endeavored to enter the contest but material difficulties in connection with her planes and engines supervened to an extent that the French failed to participate in the Schneider races. England won from Italy in 1927 at Venice with a supermarine S-5 seaplane and a 900 h.p. Napier engine. The average speed was 281.6 miles an hour.
  The next race was flown in England at Calshot in 1929. England again won, this time with a Rolls Royce engine at 1,950 h.p fitted to the supermarine S-6 monoplane and at the amazing speed of 328.6 miles an hour. A new high speed record of 357.7 miles an hour was established shortly afterward. Both Italy and France withdrew from the 1931 race at the last moment, so that England's fly over at 340.6 miles an hour has sent the Schneider trophy to a permanent resting place in the Royal Aero Club of Great Britain,
 THUS ends a world famous context which is without a parallel or a comparison in any other sphere of sport or technical development. From a rivalry between individuals the Schneider Cup race developed into a tremendous struggle in which nation vied with nation, one government against another, and the best brains, resources and technical skill of the competing countries were matched against each other to provide a most unique spectacle. The results are not directly measurable by the speed records established but instead must be determined by the value of the technical results to the nations concerned. The cost has been enormous, and whether the game has been worth the greenbacks must be decided by the who played and paid. 
  Great Britain is said to have spent about $2,500,000 on Schneider Cup racers and developments since 1926. In return she has won an important national prestige which ahs helped in the world's aircraft markets and has gained knowledge of construction, design, materials and engine development which could not have been obtained in o short a period otherwise. 
  The most outstanding result of these years of competition has been the development of the aircraft engine to power ratings which are truly extraordinary. The Rolls Royce "R" type engine is the most powerful aero engine in existence, but is at the same time an engine of extreme lightens and small frontal rea. It is a giant in performance while maintaining modest physical dimensions. Although no specific details are as yet available concerning the dimensions and weight of the 1931 engine, it is understood that they are substantially the same as the 1929 engines except for materially increased output. The leading particulars of the 1929 engines were: