It's too big.
That might be the case. But why transition from the XA100/101 which was sized for the F-35A/C to something that was supposedly sized for NGAD? If F-47 performs well with a derivative engine why not just continue with the XA100/101 under NGAP and get an engine into production quicker?
I doubt very much that both XA102 and XA103 will be taken thru EMD. The quote was “two developed and operational prototypes prior to down select”. EMD will follow to create the production A102 or A103.
Like they did with the YF119/YF120.
Regarding:
This is what Sneden has said about what else is being developed under NGAP:
It would appear that these are smaller pieces of tech that can be used to upgrade existing engines to varying degrees.
They are the only two primes capable of building advanced fighter engines. Even if one does not get the contract, it makes sense to share the know how first so that both players are kept competitive in engine development. This helps stabilize the industrial base and allow future competitions from both players.
Because the "F-22 sized" F-47 doesn't need 2x42klb engines, it only needs 2x35klb. The "F-111 sized" NGADs needed 2x42klb engines.
It appears that parts of NGAP may have been backfitted/tested on F110 already, for FAXX. For the "derivitive engine" that we all assumed had to be F110-based.
There are three technologies cited as making NGAP "next generation":
One hopes it's not limited to "F-22 sized" else range is going to be a problem.
I think it's pretty well established that the F-47 is F-22 sized.
I don't think being "F-22 sized" in terms of takeoff weight necessarily means range problem IMO, given advances in airframe design.
I think it's that the MTOW hasn't really changed but for the F-22 it only reaches MTOW with 4x 600gal fuel tanks under the wings while F-47 is ~85klbs without external tanks.
I wonder if Boeing is planning to use the 'topological optimization' technique (it's a buzzword in 3d Printing) to significantly reduce the volume of internal airframe load bearing structures without compromising on structural integrity). A Google gemini query does reveal Boeing investigations in topological optimization, though of course not for the F-47.
That's a given and has been said as much before afaik although not directly naming any tech terms.
Right but if, "has to fit in a HAS designed in the 70s" is still a requirement that's going to limit you. We don't want a Fat Amy 2.0.
====================================================================================================
Parameter F-15C (F100-PW-220) F-22A (F119-PW-100) F-47 (AETP / 6th Gen)
====================================================================================================
Development Period / EIS 1970s–1976 1990s–2005 2020s–2030s
Engine Type Turbofan (2 streams) Turbofan with TVC Adaptive Turbofan (3-str)
Dry Thrust (per engine) ~65.2 kN (14,650 lbf) ~116 kN (26,000 lbf) ~135–145 kN (30.3-32.6k lbf)
Afterburning Thrust (1x) ~105.7 kN (23,770 lbf) ~156 kN (35,000 lbf) ~195–210 kN (43.8-47.2k lbf)
Total System Thrust (2x) 211.4 kN (47,540 lbf) 312.0 kN (70,000 lbf) ~390–420 kN (87.6-94.4k lbf)
Engine TWR ~7.8 : 1 ~9.0–10.0 : 1 ~12.5–14.0 : 1
SFC (Cruise) ~0.72–0.78 lb/(lbf·h) ~0.62–0.68 lb/(lbf·h) ~0.45–0.52 lb/(lbf·h) (-30%)
Turbine Inlet Temp (T3) ~1400–1450 °C ~1650–1700 °C ~1950–2100 °C
====================================================================================================Knee jerk? I'm old enough to remember the ATF program. Long before they rolled out the prototypes they were testing prototype engines, radars, IRST, etc. There were programs to advance the state of the art for sensors and computers. So far for F-47 (let alone F/A-XX) we're not seeing any of that.
That we know of, or more accurately - that's been reported on anyway. @quellish might know. I remember years ago it was already reported that long lead items (of which engines were one of them) were being developed. Just not which specifically.
That was caused by the length limit of the Navy gator-freighter elevators. Else the F-35s would have been a lot longer for better fineness.
You mean for F-47? Probably about the time someone ran the first cost estimates for an F-111 sized monster (50tonne MTOW) with a pair of F135s or XA100/101s.
F-4 wasn't "USAF main fighter" by design (they didn't even spec one, they spec'd TACOM fighter-bomber, which was the F-105 and then F-111).
I mean, never has a new fighter jet been smaller and lighter than the previous one. So why is this being claimed for the F-47?
Cost
| Aircraft | First Flight | Unit Cost | DoD Budget | Cost as % of DoD Budget |
|---|---|---|---|---|
| F-102 | 1953 | $1.18M | $41.2B | 0.0029% |
| F-106 | 1956 | $2.95M | $40.6B | 0.0073% |
| F-15 | 1972 | $27.9M | $77.7B | 0.0359% |
| F-22 | 1990 | $137.5M | $299.3B | 0.0459% |
| F-47* | 2025 | ~$300M | ~$850B | 0.0353% |
(c)
Given that ADCOM got absolutely nothing - here's your answer. And F-22 is yet another step back in terms of optimization for interceptor profiles. Which doesn't mean that either isn't capable of doing interceptor mission - they are, given their great performance and powerful sensors. They can. Just much worse than an optimized design would("190 IMI doing work of 270 F-15s, better"); a difference with a purpose-built design is greater still.
Both BA and LM have their own proprietary airframe optimization programs and techniques. They are quite in-depth. I would assume that NG has something similar.
More than likely would be flying/testing with surrogate (dummy) panels for any items on the OML and mass simulators for internal items. B-21 did exactly that (and could still be doing so) while certain components were still in late-stage development. No need to have them all ready for initial flight testing when you're more focused on envelope expansion and systems checks.
I realize what caused the F-35 length issue. But the HAS requirement caused the ATF restrictions. If you keep those restrictions but increase the weight another 10k. . . Fat Amy 2.0. If it's not a requirement then no problem, they can make it as long as they need to.
Ever heard of inflation?
IIRC, the X-44 MANTA, the stretched, tailless-delta F-22 variant would still fit into the HAS.
