'F-110' (which seems to have been an early designation for the F-4)
<Anorak Mode> ON
The F-110A was the USAF's initial designation for the F-4C before the unification of the USN and USAF designation systems, in, IIRC, 1962ish. Thus, the next project was F-111....
Depending on who tells the story, the USAF either produced a land-based optimised fighter, or buggered about with a perfectly good aeroplane because it had to be "better" (read: different) to the USN's version. Again, IIRC, there were surprisingly large differences between F-4B and F-110A and RF-110A - the USAF ones had different wheels and tyres, for example.
<Anorak Mode> OFF
S41