Originally Posted by LO
The IHPTET T/W goal was 20:1, which is 2x better than we do today (F414/EJ200 are close) and 3x better than the F135.
I was pretty close to IHPTET at the time and it was recognized that it would, in the appropriate cycle, provide you with the dry thrust needed for non-afterburning VL (the use of A/B having been recognized as a nonstarter by then.)
The ATFE was always aimed at 10:1, but that didn't take a 2D nozzle into account, which is why the F119 is relatively heavy. If the F135 was a 10:1 engine it would weigh 4000-4300 lb (depending on whose thrust figures you believe) but it weighs 6500+ lb (says P&W). That's a lot for a length of straight jetpipe and some thermal-management kit.
The pratt provided 6500+lb weight figure for the F135-PW-600 (the version for the F-35B) includes the lift fan, roll posts, driveshaft, and 3BSM.
The F135-PW-100 and F135-PW-400 don't have all that extra junk (they are comparable to traditional jet engines with some stealth radar/ir features added and in your words are the jet engine core with a "length of straight jetpipe and some thermal management kit"). The weight for the F135-PW-100 is around 3,750 lbs. This would put the thrust to weight ratio of the actual F135 engine at around 11.467.
If you are comparing a F135-PW-600 to a legacy engine it is an apples to oranges comparison because legacy engines don't have all the STOVL equipment.