Space Age Super-Fighters

In the half century or so after the Wright Brothers' first flight the performance of aircraft with regard to speed and altitude advanced exponentially. At the start of World War I, a scarce decade after that first flight, planes could fly as fast as seventy-five miles an hour and reach altitudes of twenty thousand feet. By the end of the war four years later those figures had doubled, and they doubled again during the interwar period, while World War II accelerated the advance once more. The conflict saw prop fighters doing four hundred, close to five hundred, miles an hour, and the first jets flying into action even faster than that. In another decade, the top speed of those jets was mere cruising speed for the fighters becoming standard in air force inventories, which could do Mach 2 or better on afterburner--while even passenger travel looked set to go supersonic (with Britain and France collaborating on the Concorde).

It seemed natural that planes would continue to become faster and higher-flying--the more so for the even more dramatic progress in the field of rocketry. The World War II-era V-2s led to rockets that could reach escape speed (twenty-five thousand miles per hour) to leave the atmosphere entirely in the same time frame, putting into orbit unmanned satellites, cosmonauts, and beyond that, who knew? Meanwhile, those rockets' smaller cousins revolutionized the field of air defense--surface-to-air missiles meaning in the view of many that planes would have to become faster and higher-flying to escape them. Scarcely after their production run had begun the B-52 Stratofortress no longer appeared stratospheric enough in the eyes of U.S. Air Force planners, the coming years apparently demanding planes that could fly at Mach 3 at 70,000 feet or higher--and in turn, interceptor aircraft that could match that performance, for when Soviet bombers became equally capable. Thus the B-70 Valkyrie, and the F-12 and F-108 fighters.

Of course, none of these projects amounted to all that much, and nothing comparable was ever set up in their place. Instead of the B-70, canceled after the expenditure of over ten billion dollars in today's terms (which works out to about five billion per prototype), what the Air Force got was the modestly supersonic B-1, and the subsonic B-2, the emphasis placed on sneaking under radar, and then hiding from it in plain sight with the help of stealthy shaping and material, rather than somehow trying to get beyond its reach.

The F-108 never even made it to the prototype stage, while the spectacularly expensive F-12 (for the cost of one of which the Air Force could purchase a half dozen Phantoms) was also cancelled. Only the latter had much of a legacy, in the form of a small fleet of spy planes based on its airframe, the SR-71 (32 jets total), while the fighters of the third, fourth, fifth generations were pretty much the same as those of the '50s-era second generation with regard to speed and altitude.

This was even the case with those planes' intended missile, the AIM-47. It did pave the way for the AIM-54 Phoenix, but that, too, appears underwhelming in hindsight. Because the TFX fighter program supposed to use it also came to naught, the Air Force never even fielded them, while just a single Navy plane carried them, the F-14 Tomcat. That fighter almost never used these missiles in combat, and perhaps never successfully (the few launched over Iraq apparently missing their targets), before their retirement as the more modest Sidewinder and Sparrow (and the much later AMRAAM) proved the real instruments of U.S. air superiority.

The same went on the Soviet side. Their aspirations toward a B-70 equivalent of their own, in the T-4 program, likewise amounted to little. More did come of their fighter programs, in the form of the near Mach-3 MiG-25 and MiG-31 interceptors--but these were arguably a detour from the main line of fighter development, as attested by the small numbers produced compared with other, contemporaneous models. (The Soviet Union built over 10,000 MiG-21s, and some 6,000 MiG-23s and MiG-27s--but only a little over 1,000 MiG-25s. Later the Soviet Union and the Russian Federation would build over 1,600 MiG-29s, and counting all variants, a similar number of Sukhoi-27s, but just 500 MiG-31s.)

Considering the visions of versatile, near-space-flying hypersonic combat aircraft (a different technical problem from the hypersonic missiles getting so much press now), and the other wild-seeming possibilities so prominent in talk about sixth generation fighters, I wonder if a half century later those speculating about these matters are not equally far off the mark--and never even suspecting it because they are more ignorant of the history than they realize.