The interesting thing to me (as a former AFSC program office guy) is this:
1. No fly off for the TFX/F-111, which had some problems and despite being designed to fulfill two very different USAF/USN missions ended up being used for a smaller range of missions than the F-4.
2. No fly-off for the F-15, an uncompromising air to air superiority fighter. Result probably was the most successful fighter since WW2, which also developed into an outstanding attack aircraft.
3 Fly off conducted for the A-10 and A-9 and the result was a terrific ground attack aircraft.
4. Fly off for the F-16/F-17 and the result was we bought BOTH of them, the F-17 being the prototype for the F-18. This reminds me of the P-35/P-36, in which we ended up buying both of them but the P-36 proved to be better while the P-35 was but a stepping stone to the P-47.
4. They vowed they would go back to fly offs for the ATF and both the F-22 and F-23 prototypes were built. But the F-22 proved to be too expensive to buy enough aircraft to get the job done and so expensive to operate that they are eagerly awaiting the F-47. And of course, as usual, there are those who say the F-23 should have won.
5. Fly off with the Boeing X-32 and Lockheed Martin X-35.
5. No fly off for the F-47.
So, are fly offs a good idea or not? Or is it better to buy paper airplanes? The results are mixed, to say the least.