SteveO said:
In hindsight I think if the STOVL requirement had been kept out of the JSF program the USAF and USN could have got themselves a much lower risk, higher performance design that could have provided the cost savings they hoped for.
It might possibly have looked like the sleeker MDC/NG/BAE concept with an off the shelf F119 engine and 3D thrust vectoring nozzle. It would have been interesting if the airforce and navy could have agreed on a single variant rather than seperate CTOL and CV variants ;D
A pure ASTOVL airframe and engine design could still have shared many systems.
You've got to keep in mind how this all came about. Congress in 1994 thought it would be a good idea for one plane to perform similar missions for the three air arms, and ordered ASTOVL to be merged into JAST. During the '90s a number of engineers salivated at the prospect because it would be a great engineering exercise. The then current Administration liked the idea because it would set a good schedule to "triangulate". Specifcally, they could further cut the number of F-22s, while simultaneously proclaim they were moving forward on a superior strike aircraft but structure the schedule so that the big money would have to come in the next Administration.
As so often becomes the case in these kind of joint exercises, the mandate evolved into, "Build what USAF wants, and any changes the other services need will have to be variations on that". USAF had mixed feelings about the program in the sense they wanted the plane to be good, but not too good lest it threaten the F-22.
So this question might be asked another way as well: What would the Marines' Harrier replacement been like if they hadn't been forced into JAST? Now, the F-35 will meet their basic requirements because what they were looking for was a STOVL CAS machine, and a STOVL F-35A meets the bill, in fact does more than they need They're fully on board because they knew by riding along they could get what they wanted without having to take all the incoming fire themselves. Still, given what they wanted the plane to do, had they been allowed to go their own way one has to wonder if they would have cared that much about supersonic performance or even much stealth...