ORAC,.
Thanks for the response - it's always good to exchange views.
It looks as if the USAF is following the USN path and getting more life out of the F-16 as the F-35 deliveries have slipped. I would note that previous attempts to get more airframe life out of the F-16 fleet have not been a roaring success, and the RFP stuff you kindly supplied indicates a possible max of about 490 F-16s affected. The F-15X is still a proposal from Boeing, no sign of the USAF going there yet.
Yes, I'd absolutely agree that a 'clean sheet of paper' design for a USAF replacement for the F-15 and the F-16 would have been very different to the F-35A. Whether it would have been affordable as a separate programme is another matter. The USAF is just as good at 'gold plating' a requirement as any other Air Force.
I would offer the thought that the F-35 family has a little more commonality than some people think. Avionics and weapons systems are massive cost drivers for combat aircraft, and these systems are (I am led to understand) almost completely common across the three fleets. There are also common items across the main engines, another big cost driver. Ditto many of the aircraft systems components in the fuel, hydraulic, thermal management and electrical systems, as well as life support and escape. Also training and support programmes. And the fact that a single line is assembling and delivering all three variants.
Best regards as ever to the smart people managing the transition from one fleet of aircraft to another.
Engines