Back in the day, U.S. fighter planes were designated by P-(number,) e.g. the P-38, P-47 and P-51 of WWII fame. god knows why. But then they started being called the F-(number) such as the F-86 Sabre, F-100 Super Sabre, F-101 Voodoo, etc.
But eventually I guess they got tired of high numbers and went back to zero, so at some point F-numbers seem to have started over.
Wasn’t the F-21 the IAI Kfir, used for aggressor training?
I have heard that the F-11x numbers were used for captured Russian aircraft used in aggressor training, and that F-117 was selected for the stealth fighter to deflect public attention. Everyone seemed to have made up their minds that it was the F-19 and that it looked a certain way, so I imagine reference to an F-117 wouldn’t draw so much attention.
For the F-117, they went back to the older numbering system that had been abandoned in the '60s because the numbers were getting so damned high…the F-111 being the last of these designations. Unfortunately, the current generation of fighters (starting with the F-4 Phantom II) doesn’t quite fit into the available spaces in this numbering scheme…so I suspect the Pentagon merely got annoyed by the press labeling it the “F-19” and designated it the F-117 just to thumb their noses at the know-it-alls. This would explain why the F-117 is the only break in the current pattern.
BTW - the F-17 Cobra was a failed Northrop prototype that was purchased by McDonnel-Douglas, redesigned and improved, and became the F-18 Hornet.
Crusoe is right about the Kfir being the F-21 and a limited number being used for Aggressor training. I’ve never heard of F-11x numbers being used for captured Russian aircraft…that would seem to be a greater source of confusion than just giving them callsigns.
“P” was for “Pursuit”, but nobody called 'em “Pursuit Planes” so the powers-that-be changed the designation in the very late '40s to “F” for “Fighter”. It was at this point that the P-51 (still in service at the time) became the F-51, the P-80 became the F-80, etc…
One of the F-117 squadron commanders in the Gulf War gave a talk about it at our company, and was asked this very question. Nobody seems to be really sure, implying it fell through the bureaucratic cracks somehow.
Anyway, the F-117 designation was used for radio communications at Edwards and elsewhere, as crusoe suggests, while the program was still “black” Earlier numbers were indeed used as codes for planes whose possession by the US was intended to be secret. The pilots themselves called it “the black jet” to each other.
The F-19 official designation was set aside for the plane when it became public. However, since the curtains were pulled back a little earlier and perhaps more hastily than expected, the official designation somehow didn’t get assigned properly, and the F-117 code name became so public so quickly that USAF just kept it.