The MiG-21 won plaudits from American aggressor pilots at Red Flag, who celebrated its speed and maneuverability, and played (through the contribution of North Vietnamese aces such as Nguyễn Văn Cốc ) an important role in redefining the requirements of air superiority in the United States. When flown well, it remains a dangerous foe.
Most of life is about just showing up, and since 1960 no fighter has shown up as consistently, and in as many places, as has the MiG-21. For countries needing a cheap option for claiming control of their national airspace, the MiG-21 has long solved problems, and will likely continue to serve in this role.
What to say about the F-15 Eagle? When it came into service in 1976, it was immediately recognized as the best fighter in the world. Today, it is arguably still the best all-around, cost-adjusted fighter, even if the Su-27 and F-22 have surpassed it in some ways. If one fighter in American history could take the name of the national symbol of the United States, how could it be anything other than the F-15?
The Eagle symbolizes the era of American hegemony, from the Vietnam hangover to the post-Cold War period of dominance. Designed in light of the lessons of Vietnam, at a time where tactical aviation was taking control of the US Air Force, the F-15 outperformed existing fighters and set a new standard for a modern air superiority aircraft. Despite repeated tests in combat, no F-15 has ever been lost to an aerial foe. The production line for the F-15 will run until at least 2019, and longer if Boeing can manage to sell anyone on the Silent Eagle.
In the wake of Vietnam, the United States needed an air superiority platform that could consistently defeat the best that the Soviet Union had to offer. The F-15 (eventually complemented by the F-16) provided this platform, and then some. After the end of the Cold War, the United States needed an airframe versatile enough to carry out the air superiority mission while also becoming an effective strike aircraft. Again, the F-15 solved the problem.
And it’s a plane that can land with one wing. Hard to beat that.
A Contest Based on Parameters:
Again, this exercise depends entirely on decisions about the parameters. A different set of criteria of effectiveness would generate an entirely different list (although the F-15 would probably still be here; it’s invulnerable). Nevertheless, the basic elements of the argument are sound: weapons should be evaluated in terms of how they help achieve national objectives.
Honorable mentions include the North American Aviation F-86 Sabre, the Fokker D.VII, the Lockheed-Martin F-22 Raptor, the Messerschmitt Bf 109, the Focke-Wulf Fw 190, the Supermarine Spitfire, the North American Aviation P-51 Mustang, the McDonnell Douglas EA-18 Growler, the English Electric Lightning, the Mitsubishi A6M Zero, the Sukhoi Su-27 “Flanker,” and the General Dynamics F-16 Fighting Falcon.