Very true, S82 – and what is now unusual about the F-35 is the duration of concurrency, with (correct me if I am wrong) nine LRIP lots. That will result in a lot of non-standard aircraft. Some can be retrofitted economically, but I expect that we’ll see a lot of jets like the Block 20 F-22s, confined to test and training and not economically attractive to fix.

Nic – Don’t use facts on the JSF fankiddies, it gets them all upset.

We have yet to see when the JSF reaches IOC and how “mature” it is. At that point, the fans can declare victory, but not seven years away from IOC – not given the program’s record.

Also, the program did not “decide” when IOC should be – that declaration and the standards for it are set by the operational commanders.

Nor was JSF initial planning affected by experience with the F-22 – at the time that the SDD contract was awarded, everyone was blithely predicting full AA capability at IOC followed by a rapid series of Global Strike upgrades, and the true believers thought that would lead directly to an FB-22.

I don’t think there is any threat to already-budgeted F/A-18s. The fulminating politicians are trying to stall any plan that cuts back on any F-35 variant. Banning additional Hornet orders leaves the Navy with no options except the F-35.

Interesting question – because when you think about it, LPI is fundamental to air-to-air stealth.

We don’t know that much about LPI techniques, although the paper cited above is interesting.

We don’t know how much today’s achievable LPI compares with the hopes and plans of 1985.

We do know, however, that fighters have become more difficult radar targets since 1985 – which is apt to make LPI more difficult insofar as it implies using the minimum energy on target.

Targets have become more difficult because of:
– Frontal sector X-band RCS reduction
– Much improved passive EW with greater bearing accuracy
– Cooperative passive tracking that can provide very rapid location
– More directional and more responsive active EW enabled by phased arrays and DRFM

Did the standards for LPI established in the ATF program take account of all those developments?

By the way, F-35A/B wingspan is set by LHA/LHD deck parking limits, weight constraints (no fold) and commonality.

“The F-22 and PAK-FA are quite different from the J-20, in that both have extensive cambering of their upper fuselage surface (the PAK-FA through the LEVCON). The J-20 doesn’t, and uses the longitudinal vortices induced by a sharp AoA over the LERX to create lift.”

Interesting point, Amiga. Where does the JSF fit in that picture? Because once you start looking at net vs. gross wing area (measured with root chord and root-to-tip distance) the A/B are not exactly over-endowed with wing.

Geogen –

There were a few people who suggested in the late 1990s that there should at least have been a formal evaluation of an approach that would have emphasized commonality at the parts level (avionics/cockpit, subsystems, engine core, structural technology, LO materials) but that would have different versions. (It’s how Airbus creates different types.)

Nobody listened, and the people who did not listen fell into three groups. There were the “don’t upset the applecart” types who worried that any wavering would result in another complete replanning of tacair re-equipment that would take years.

There were the optimists who really thought that you could meet the cost and schedule goals of the late 1990s.

And I’m sure there were those who knew damn well that those goals were ultra-optimistic but knew that by the time the first two groups recognized the truth, it would be too late.

Another problem, by the way, was that an approach with two or more configurations would immediately show how much STOVL cost.

BTW The P1216 design is ultracool, but its exhaust is emphatically not.

+1 Amiga500

“Blocker” is perhaps the wrong word for what you need to substitute for full LOS-blockage serpentine ducts.

You don’t need to block the compressor face or even absorb much radiation. The goal is to make sure that no signal gets to the face and scatters out of the inlet without bouncing off the duct walls. What you need is more of a deflector.