After years of gossip and rumors, on November 10, 1988, the existence of the Lockheed "stealth fighter" was finally officially revealed by the Defense Department. It turned out to be an attack aircraft rather than a fighter, since it apparently has no air-to-air capability. At the same time, it was also revealed that its designation was F-117. It seems that the F-117 designation has nothing to do with the old fighter sequence which ended at F-111, in spite of rumors that the Soviet fighters under test at Groom Lake conceal their real identity by using call-signs such as F-112, F-113, and so on. During its development and test phase, the Lockheed "stealth fighter" was known strictly under its project name of Senior Trend, and never carried any designation at all, certainly not a designation of F-19. Although the real origin of the F-117 designation is still not known with certainty, it seems to have been derived from the strict security restrictions that were in place at Groom Lake during the flight testing--pilots flying the Senior Trend test aircraft were not allowed to tell anyone what type of aircraft they were flying, and so whenever asked to fill out routine forms that requested identification of the aircraft type they flew they would fill in the meaningless number 117. When the first manual for the Senior Trend aircraft appeared, it had F-117 printed on its cover. Since it would cost too much to have the manual reprinted, the designation later became official.

It is now known that the designation "F-19A" was officially skipped at Northrop's request. Since the F-5G turbofan adaptation of the F-5F was basically a completely new design, the company wanted to have a new designation assigned to it. The next designation in line would be F-19, but Northrop preferred an even number because the Soviet competitors in the export fighter market of the early 1980s all used odd numbers, and Northrop wanted to stand out from these. So the official "confusion with MiG-19"-story isn't all that far from the truth, although it is certainly rather misleading. It is unlikely that anybody would ever confuse an "F-19A" with a MiG-19, especially because the latter was already obsolete. The F-20A designator was approved despite official recommendation by the USAF Standards Branch (at that time responsible for nomenclature assignments) to follow the regulations to the letter and use "F-19A" for the redesignated F-5G. Presumably this change would also make for better advertising copy--"The Northrop F-20: First of a new generation of fighters", for example.

A similar sort of thing happened during World War 2 when the designation P-74 (and perhaps P-73 as well) had been deliberately skipped at the request of the Fisher Body Division of General Motors who wanted their new heavy escort fighter to carry the designation P-75 for advertising reasons.

Mmm, accurate models produced from a crashed plane. Last time I saw a crashed military aircraft it would have been difficult to accurately model it unless i got a meccano set and threw all the bits in a pile...