COOCH MEMORIAL LECTURE Thursday l8th November at the Central Library, Worthing.
Speaker: Dr. E. Mowforth, Senior Lecturer, Surrey University.
“THE HISTORY OF HIGH SPEED FLIGHT.”
In introducing Dr. Mowforth, an authority upon his subject, the President also gave a cordial welcome to visitors and an explanation of the party played by the late Mr. Cooch in the early days of the Association.
Dr. Mowforth began with the observation that the desire for speed in flight is as old as the desire for flight itself, and it is significant that the Federation Aeronautique International (FAI), the body responsible for ratifying all international records, came into being in time to record, on the occasion of the first officially-observed flight in Europe, world air speed and distance records of 25.658 mph and 0.14 miles respectively.
An appreciation of the value of streamlining soon began to develop, and a leading pioneer in the field was the French designer Bechereau, whose elegant monocoque-fuselage Deperdussin monoplane of 1913 raised the speed level to 127 mph – speed to be out of reach of most military aircraft throughout the ensuing World War I. 1913 also saw the first of the Schneider Trophy contests, intended by their founder to lead, to more rapid development of commercially viable marine aircraft. In the event these contests, in which temperamental racing machines sought international prestige. The main contestants were Britain, Italy and the USA, and the state-backed aircraft raised the world speed record well above the levels attainable by contemporary landplanes, culminating in 440.68 mph which was set by the Macchi MC72 in 1934 – 3 years after the Trophy had finally been won by Britain – and remained unbeaten until 1939.
The highest landplane speeds were meanwhile being achieved in the many air races taking place in the USA, outstanding aircraft being the Gee Bee racer and the Hughes H-l.
The world record was not, however, returned to landplanes until 1939, when the Heinkel He 100 and the Messerschmitt Me 209Vi, raised the record to 464 and then469 mph. This record stood for piston-engined aircraft until 1969, when a Bearcat achieved 482 mph in the USA.
By the end of World War II, propeller-driven performances had been decisively eclipsed by rocket and jet-propelled aircraft, and the latter were to raise the world speed record to 755 mph. by 1953. Further advances were limited by the approach to the speed of sound. FAI rules still limited the measured mile at an altitude of 100 m, and supersonic records were not set up until a revision permitted runs at safe heights from 1955 onwards. Records then rose rapidly, reaching 2193 mph in 1976. It is likely that many military aircraft could now beat this, but official attempts are probably discouraged on the grounds of secrecy.
Even higher speeds had been reached by the series of rocket-powered research aircraft used to investigate transonic and supersonic flight phenomena in the USA between 1947 and 1969. The last of this range, the North American X-15, achieved at different times a speed, altitude and skin temperature of 4534 mph,354200 ft and 715 deg C. The speed could not be counted as an FAI record because the X-15 was launched from a carrier aircraft.
By the middle fifties there were many standard fighter aircraft capable of exceeding the speed of sound in level flight; swept wings were standard, and new ‘delta’ geometries were appearing, offering efficient flight at high supersonic speeds. These wings, unfortunately, had very poor characteristics at low speeds, limitations which were acceptable only when lengthy runways were available – For the ‘field’ operation called for by close-support military aircraft it became necessary to develop variable-geometry aircraft using at low speeds a conventional-looking ‘straight’ wing that could be folded back towards a delta geometry for supersonic flight.
Ultimately the achievement of ever higher speeds has rested upon power plant development; the Schneider Trophy races ‘forced’ the development of many new piston engine techniques, and the post-World War II race for speed, mainly now for military purposes, accelerated the development of turbojet engines of very high thrust.
It seems at the present time that commercial applications of supersonic flight, as pioneered by Concorde, have reached something of a dead end for purely economic reasons. Combat development, however, will undoubtedly continue, and may lead to further technical breakthroughs offering new paths for civilian aircraft to follow at reasonable cost levels. Time will tell.
In the lively discussion which followed, Dr. Mowforth said he could see little prospect of renewed interest in flying boats. They could not compete with land planes once airports had been built. Only a need for very big craft, say 1,000 ft. wingspan might revive them. airport nuisance is becoming of increasing concern. V.T.O. offers no prospect of benefit, all forms are noisy and also heavy and fuel hungry. The latest turbo-fan engines, on the other hand, are significantly quieter and they give faster rates of climb.
Mr. Smith in his vote of thanks, registered his approval on behalf of all members to Dr. Mowforths most interesting lecture, presented so historically and dramatically. High speed flight was undoubtedly the aeronautical engineers achievement, but members might like to reflect on other engineers contributions such as mechanical engineers with engines, chemical engineers with fuels and even: earthbound oivil engineers with airfields.
The meeting closed with a most hearty acclaim to Dr. Mowforths efforts and presentation.