I T is challenging to have the opportunity to present views regarding aircraft at this time, in the second half of the 1970's, since the western aviation world has just witnessed and is still witnessing, after a pause of some 15 years, a wave of new designs being developed and launched into production and service. Some of these new airplanes will dominate the scene for the next 15 years or more, that is, well into the 1990's. Nevertheless, are we already entering the period where concepts for yet another generation of fighters are being developed? The evolution of the aircraft, and there have been a number of revolutionary steps, commenced with powered flight as pioneered by the Wright Brothers. A brief review of this history may provide a better perspective for our views, even if the author of this paper is not a researcher of aircraft history and therefore may not be accurate in detail. The initial generation of aircraft (in W.W.I) had to solve the problem of developing an effective armament, the art of maneuvering flight having been provided by the Wright Brothers only a few years earlier. The unarmed early airplanes were nevertheless providing effective reconnaissance and were as such already fighters. The Wright Brothers thus delivered the world's first actual to the U.S. Army Signal Corps. The armed fighter was, in effect, only a reaction to an earlier airborne threat to the land and naval forces. The initial armament of handheld guns was soon overtaken by the aircraft-mounted machine gun, but it was difficult for the pilot to control the airplane with one hand and to point the gun with the other, especially if a propeller in the front was in the way of the natural line of sight. The obvious solution of taking a weapons operator or gunner along was detrimental to the fighter's rate of climb and speed. The other solution of reverting to a pusher installation of the engine also resulted in a heavier airplane. The truly ingenious solution was that of firing through the tractor-propeller with a rigidly mounted gun and accurately pointing and aiming by controlling the direction of flight and attitude of the aircraft. The propeller was protected first by local armor and later by a synchronizing system. This system was, I believe, invented by R. Garros of France in 1915, met instant success, and set a pattern which is still valid. I am recounting this well-known history because I believe that it really started the fighters as a special breed of airplane (see Fig. 1). After its birth, the aircraft during the next 20 years evolved apparently with the main aim of maximum l-g SEP or rate of climb. This was done by increasing engine power in a number of steps from 80 hp by a factor of 10 while improving specific weights such that gross weight increased from 1100 Ib by a factor of 3.5 only. (Power loading by 2.85.) Airframe size changed little in this period; it was built around the pilot with a wingspan of 30 ft. Aerodynamics must have been subordinate to the structural designers who retained the light, simple, and well-proven externally braced and fabric-covered designs. Materials remained generally steel tube and wood, even though aluminum had already been used for the Zeppelin airships. This type of construction also had the advantage of being easy to repair. By the early 1930's, however, the designers of airliners and bombers really started to apply aerodynamics, including retractable landing gears, and combined this with higher wing loadings and stress-skin aluminum structures. They were outspeeding the contemporary fighters, which did only about 230 mph with an engine of 600 hp. The community had to react since it could not justify its existence for long by pointing out how excellent they remained in fighting their own
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Apr 1, 1982
