F-15X: USAF Seems Interested

And I think your milcon estimate is understated.

And I think your milcon estimate is understated.

Could be. It's just total AF MILCON in the SAR (TY$) / total Air Force quantity.

I'm happy to have other estimates.

What is the per-base cost?

Tail numbers 4001 thru 4195 include the first 8 flight test aircraft. 187 production configuration F-22A aircraft.

I have to ask, is F119 bigger than the F110 and won’t fit in an F-15? I thought I read some time ago F119 barely fits.

Yes, the F119 is significantly larger than the F100 and F110 engines installed in the F-15 variants, and is mounted differently. It would take a major modification to the rear fuselage to fit the F119, and center of gravity would also a significant issue to resolve.

Lets go through it, call it the "F-15MAX" and just sell the flight control software that fixes the Center of Gravity as future Downloadable content while we park the fleet?

Here are the SAF/FM milcon docs just for FY19 and 20.

https://www.saffm.hq.af.mil/Portals/84/ ... 173403-060
https://www.saffm.hq.af.mil/Portals/84/ ... 120911-810

Eielson F-35 milcon in FY17 was $295M — https://www.saffm.hq.af.mil/Portals/84/ ... 102005-467

Miramar was $200M for starters w another $250M slated for other improvements shortly to follow.

https://www.secnav.navy.mil/eie/Documen ... iramar.pdf

[qoute=“XanderCrews”] Lets go through it, call it the "F-15MAX" and just sell the flight control software that fixes the Center of Gravity as future Downloadable content while we park the fleet?[/quote]

What do you think - should we keep the F119 vectoring nozzles, or should we go with a lighter round F100 style nozzle?

It's questionable if the F-15EX will survive the coming Defense Budgets after the "Coronavirus". So, forget about future versions of the Eagle.


"IMHO"

What do you think - should we keep the F119 vectoring nozzles, or should we go with a lighter round F100 style nozzle?

Exactly what I was thinking, the TVC nozzles are part of the F-119's design. I got into a discussing with someone saying that the F-119 does not produce 35K of thrust because square nozzles are known to reduce thrust rates by up to 14%.

after some digging, I found that PW called the TVC nozzles "standard" on the F119 meaning that all tests were probably done with the square nozzles. furthermore, the YF-119 prototype also had square nozzles and 35k of thrust was a requirement for the ATF program.

So this leads me to believe that simply swapping out the TVC nozzles for regular round ones may not be as easy as we think and may require extensive testing. It will be better to use the F-135 engine, already in production, has round nozzles by default.

The F119 and/or F135 wouldn't fit. Nor, is it ever going to happen.........

The F119 and/or F135 wouldn't fit. Nor, is it ever going to happen.........

Thats right, I was also thinking why? why not go with advanced derivatives of the F100 or F110? The F-15EX will probably be assigned to Guard units for your routine Russian bear intercept.

Is it to improve performance? If you want performance, send a Raptor, it'll make short work of the occasional phonebooth fights that may happen, if the Raptor is not available go with the F-35A,

I understand that the F-15 is no longer as respected as it once was when it comes to max performing the jet and any improvement is welcome, but theres only so much you can do with 1960's aerodynamic technology, at the end of the day the F-15, even this new EX variant will be the 3rd line of defense after the Raptor and F-35 respectively.

What do you think - should we keep the F119 vectoring nozzles, or should we go with a lighter round F100 style nozzle?

Exactly what I was thinking, the TVC nozzles are part of the F-119's design. I got into a discussing with someone saying that the F-119 does not produce 35K of thrust because square nozzles are known to reduce thrust rates by up to 14%.

after some digging, I found that PW called the TVC nozzles "standard" on the F119 meaning that all tests were probably done with the square nozzles. furthermore, the YF-119 prototype also had square nozzles and 35k of thrust was a requirement for the ATF program.

So this leads me to believe that simply swapping out the TVC nozzles for regular round ones may not be as easy as we think and may require extensive testing. It will be better to use the F-135 engine, already in production, has round nozzles by default.

The engine has had square nozzles all the way back to the first PW5000.

Actually, this first development PW5000 (i.e. XF119) ground test engines ran with a round nozzle - it was on the cover of Aviation Week back in the day. But that was just for convenience, since the 2D nozzles took a long time to get working - especially with the change from a thrust reversing requirement initially in Dem-Val that went away for the flight demonstration and the subsequent EMD development of the production F119.

Also, don’t believe the Russian propaganda that the 2D nozzle reduces thrust by 14%. There are a lot of challenges in minimizing air leakage on a 2D nozzle that can impact thrust, but a properly designed and built 2D nozzle has minimal thrust impact, and having full control of the divergent part of the nozzle has great benefits beyond giving thrust vectoring capability.

Actually, this first development PW5000 (i.e. XF119) ground test engines ran with a round nozzle - it was on the cover of Aviation Week back in the day. But that was just for convenience, since the 2D nozzles took a long time to get working - especially with the change from a thrust reversing requirement initially in Dem-Val that went away for the flight demonstration and the subsequent EMD development of the production F119.

The PW5000 got a 2D nozzle pretty early. There were pictures of it on the test bench.

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Thats right, I was also thinking why? why not go with advanced derivatives of the F100 or F110? The F-15EX will probably be assigned to Guard units for your routine Russian bear intercept.

Is it to improve performance? If you want performance, send a Raptor, it'll make short work of the occasional phonebooth fights that may happen, if the Raptor is not available go with the F-35A,

I understand that the F-15 is no longer as respected as it once was when it comes to max performing the jet and any improvement is welcome, but theres only so much you can do with 1960's aerodynamic technology, at the end of the day the F-15, even this new EX variant will be the 3rd line of defense after the Raptor and F-35 respectively.

Every generation we hear the same thing. When the F-15 and F-16 started to come into service. We heard the F-4 Supporters beating the drum beat for upgraded F-4's instead of new Eagles and Vipers. (sorry Fightning Falcons)

Wasn't a good idea then and isn't a good idea now........

That said, nothing wrong with upgrading older aircraft as a stop gap until newer ones come online. Honestly, this is the problem with the F-15EX. As you could easily just upgrade the existing F-15C's or even better F-16C's.

Every generation we hear the same thing. When the F-15 and F-16 started to come into service. We heard the F-4 Supporters beating the drum beat for upgraded F-4's instead of new Eagles and Vipers. (sorry Fightning Falcons)

Wasn't a good idea then and isn't a good idea now........

Well to me it depends on what the "new generation" is. The F-15 was better than the F-4 in all aspects of the A-A mission, from long range intercept to ACM.

On the Flip side the DDG-1000 was not better than the Arleigh Burke in BMD and deep water combat operations so they scrapped it and went with upgraded Burke's instead.

From what I read the Virginia class is actually a cheaper and a bit less capable version of the sea wolf class, at least the early models. maybe the newer flights have reached the sea wolf's capabilities.