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F-X: Multirole from the start?

isayyo2

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Many have read the quote "Not a pound for air to ground" from the F-15 program office during the 70s, though most of us here know the F-15 has always had a latent A-G capability. Paul's post in 2008 shows a few advanced load-outs that MDD whipped up before the F-15E. So, what-if TAC held more sway during the F-15s development to keep it as a true F-4 replacement? A mach 2.5 dual crew fighter-bomber, designed to carry Maverick, HOBOS, Paveway etc in addition to the F-15s air superiority role with TISEO and VTAS.

Would it be too ambitious and face delays, forcing further F-4 modernization?
How would its multirole capability effect the LWF development?
Would it be forced on the Navy?
 

apparition13

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Or -

USAF gets an F-111 mk2, this time without Navy input, a 60k pound strike aircraft that is a follow on to the F-111. Which still leaves them without a real fighter, so with the threat of the F-14 being forced on them they go along with the fighter mafia and wind up with an air superiority optimized F-16. Which would need BVR capability, and would eventually likely get some air to ground as well, but it would be F-15s replacing F-4s and A-7s instead of F-16s, with the F-16s taking over all the air superiority squadrons. Personally I like the idea of the replacement for the F-106 being an interceptor variant of the F-16xl.

It might also make the F-16 less attractive to allies since it would be more of a fighter an less of a multi-role aircraft. Without the air superiority F-15, the F-14 and Mirage 4000 might have a niche as well. I can see F-14 to Japan, and Mirage 4000 to Saudi Arabia. Without the multirole F-16, the F-17/F-18L might get a look, or perhaps Mirage or Saab could fill that void.
 

isayyo2

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Perhaps I should have been more clear in my initial post; I wasn't looking for a totally new clean sheet design to replace the F-15, but more so if every F-15 was a twin seater with multirole capabilities equal or greater to the F-4E it replaced. That way every F-4 crew could transition into a new machine, but keep the Pilot-WSO synergy developed over Vietnam and not have the Air Force retrain many hundreds of WSOs into new roles.
 

TomS

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So, look at what it took to make the F-15 into a viable strike aircraft.
  • A bunch of structural redesign, some of it using materials technology that wasn't well established when the A model was built.
  • Improved radar, again using technology that didn't really exist in the 1970s
  • More powerful engines to offset the increased weight associated with the structural changes. And the F-15E is still not as nimble in air combat as the A or C, nor as fast in a straight line.
Trying to replicate the E's capabilities in the 1970s with a minimum change to the F-15 likely ends up with an aircraft that is significantly slower and less agile than the F-15A that was actually built. Given the pain the USAF had suffered trying to dogfight the F-4 against Soviet contemporaries, and the anxieties it had about encountering higher-performance Soviet types like the MiG-25, that's a non-starter.
 

isayyo2

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So, look at what it took to make the F-15 into a viable strike aircraft.
  • A bunch of structural redesign, some of it using materials technology that wasn't well established when the A model was built.
  • Improved radar, again using technology that didn't really exist in the 1970s
  • More powerful engines to offset the increased weight associated with the structural changes. And the F-15E is still not as nimble in air combat as the A or C, nor as fast in a straight line.
Trying to replicate the E's capabilities in the 1970s with a minimum change to the F-15 likely ends up with an aircraft that is significantly slower and less agile than the F-15A that was actually built. Given the pain the USAF had suffered trying to dogfight the F-4 against Soviet contemporaries, and the anxieties it had about encountering higher-performance Soviet types like the MiG-25, that's a non-starter.
Definitely won't disagree on engine performance, but I am going to push back on your "viable" comment.
The A-D models have A-G built into their designs, certainly not for the low-level F-111/A-6 role but it's been well demonstrated by the Israelis. Again, I'm asking about a Phantom replacement for the fighter-bomber role with Mavericks, iron bombs, and Pave Spike pods, all in service gear; the beefed up F-15E could come into service too for their unique interdiction role. The rudimentary capability was there I assure you, it wasn't funded and rarely if ever trained with stateside.

https://flic.kr/p/24E97da
1396429638965-1.jpg

scan0076-2.jpg
 

kaiserd

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The issue is that the F-15 (like the F-16) were both (initially anyway) largely optimised for air combat but always had latent potential for air to ground roles.

In particular this was always baked into the McDD F-15 design (the nature of the fighter requirements it had to fulfill were always likely to generate substantial air to ground payload/range potential/ capabilities).

The changes from YF-16 to F-16A probably reflect a more substantial change to facilitate multi-role capabilities but again it’s not like the F-16 was ever intended as a short range light weapon load interceptor/ fighter that wouldn’t have substantial potential in the air to ground role (the LWF could be seen as intended as a higher performance longer range heavier weapon load F-5, which already was carrying bombs and considered for air to ground roles).

And when the F-15 was entering service the F-111 was still in production for the USAF in the deep strike role (last F-111F 1976?), plus recently entered service F-4s, A-7s, etc. operating in the air to ground roles (plus the US airforce had to protect and pay for the LWF that be came the F-16, plus the A-10).

Hence early developments to make use of the F-15s potential in the air to ground role just weren’t a priority, only when thoughts turned to a F-111 compliment/ replacement (and bluntly fuelled by early Reagan administration moves to have money splurged on so many new defence programs) did the Strike Eagle program really get going.
 

overscan (PaulMM)

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There are two aspects to the answer. The first is the F-15 had to be air to air optimised to distinguish it from the F-4 F-111 and A-7 for political, procurement and funding purposes (as kaiserd says). A multirole F-15A would overlap with those aircraft and duplicate existing aircraft capabilities with no obvious advantages over them in the strike missions. The second is that the F-15 struggled to meet the cost targets and cut various nice-to-have air-to-air capabilities such as ATAR IRST, HMS, radar track-while-scan modes to become (just about) affordable. There was also lot of urgency in getting it into service quickly to counter the perceived Foxbat threat. Adding in ground mission capabilities would simply have increased costs and delayed the program. There was a tacit understanding in the Air Force and McDonnell-Douglas that the F-15 could do that job eventually, and indeed that's what happened down the track, when the older strike aircraft got old enough to replace, and avionics technology had advanced to allow more reliable and multipurpose avionics.
 

Pioneer

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Many have read the quote "Not a pound for air to ground" from the F-15 program office during the 70s, though most of us here know the F-15 has always had a latent A-G capability. Paul's post in 2008 shows a few advanced load-outs that MDD whipped up before the F-15E. So, what-if TAC held more sway during the F-15s development to keep it as a true F-4 replacement? A mach 2.5 dual crew fighter-bomber, designed to carry Maverick, HOBOS, Paveway etc in addition to the F-15s air superiority role with TISEO and VTAS.

Would it be too ambitious and face delays, forcing further F-4 modernization?
How would its multirole capability effect the LWF development?
Would it be forced on the Navy?
I appreciate it's 'Alternative History' that you propose, but I'm thinking that if the 100% Air Superiority stipulation was dropped for multi-role from the get-go, the FX would have remained bigger, heavier and more expensive than what it sensibly got reduced to, when the likes of John Boyd got involved

View: https://youtu.be/oC6bF4f2iiU

View: https://youtu.be/i5c3yMy-llA



Regards
Pioneer
 
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isayyo2

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Thanks @Pioneer

I would not be surprised to meet Col. Boyd's E-M theory and retain the F-4s fighter bomber mission the F-X would evolve into some Su-27/A-5 sized beast with after-burning TF-33s; which imo would be pretty slick too but ridiculously expensive. :cool:
 

Pioneer

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Thanks @Pioneer

I would not be surprised to meet Col. Boyd's E-M theory and retain the F-4s fighter bomber mission the F-X would evolve into some Su-27/A-5 sized beast with after-burning TF-33s; which imo would be pretty slick too but ridiculously expensive. :cool:
In all due respect - an afterburning TF-33 engines? I'm certain by the USAF/Pentagon/Military Industrial Complex mindset, I think the FX in any guise was going to involve a new engine. I also envisage a two-seat aircraft at least the size/weight of the MiG-25 Foxbat.

Regards
Pioneer
 

isayyo2

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Thanks @Pioneer

I would not be surprised to meet Col. Boyd's E-M theory and retain the F-4s fighter bomber mission the F-X would evolve into some Su-27/A-5 sized beast with after-burning TF-33s; which imo would be pretty slick too but ridiculously expensive. :cool:
In all due respect - an afterburning TF-33 engines? I'm certain by the USAF/Pentagon/Military Industrial Complex mindset, I think the FX in any guise was going to involve a new engine. I also envisage a two-seat aircraft at least the size/weight of the MiG-25 Foxbat.

Regards
Pioneer
Just thinking of something nutty that could put out 30k wet haha
 

overscan (PaulMM)

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Multirole fx would have similar thrust to the f-15 - without strong air air emphasis thrust weight ratio would be lower. It would have a much higher bypass ratio for fuel efficiency - 2:1 was mentioned.
 

Pioneer

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The changes from YF-16 to F-16A probably reflect a more substantial change to facilitate multi-role capabilities but again it’s not like the F-16 was ever intended as a short range light weapon load interceptor/ fighter that wouldn’t have substantial potential in the air to ground role (the LWF could be seen as intended as a higher performance longer range heavier weapon load F-5, which already was carrying bombs and considered for air to ground roles).
From what I've read over the years - well decades, the transition from the YF-16 as a 110% clear weather air superiority fighter to F-16A as a multi-role was:

-The 'Sale of the Century' European/NATO competition to replace the Lockheed F-104 (the European's wanting a multi-role jack of all trades fighter;

-The USAF seeing the true world leading capability of a cheaper, lighter and smaller YF-16 threatening their golden golden calf - the F-15 Eagle. So by using a sly of hand and political hearings, they promoted the F-16 as a multi-role fighter to replace it's F-4E Phantom II's as the bomb truck of the USAF, leaving the F-15 Eagle as their principle air superiority fighter.
This way the USAF would appease it's political masters directive of 'you will except the winner of the LWF/ACF competition!', while protecting its Golden Calf in the process. One should remember, the USAF never wanted the LWF/ACF - period.

Regards
Pioneer
 
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overscan (PaulMM)

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I'd dispute that characterisation - you are buying the Fighter Mafia party line there. The Mafia regard the F-16 as a terrible corruption of their wonderful idea, rather than the most successful fighter design of the the last 40 years. If it had stayed a day fighter with no radar, it would probably never have sold to anyone.
 

Pioneer

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I'd dispute that characterisation - you are buying the Fighter Mafia party line there. The Mafia regard the F-16 as a terrible corruption of their wonderful idea, rather than the most successful fighter design of the the last 40 years. If it had stayed a day fighter with no radar, it would probably never have sold to anyone.
My dear overscan, in all due respect, I'm a supporter of the Fighter Mafia and many of the principles they stood for and advocated. I think their work and concerns have been vindicated in the likes of the F-22 and F-35 debacles. Maybe if there wasn't such an assertive effort to undermined their concerns and efforts by the Pentagon and the Military Industrial Complex as a whole, the US Military might have had cost effective and efficient replacements in sufficient numbers for the F-15, F-16 and F/A-18 and A-10 two decades ago. Instead they've had to fall back on yet another incarnation of the F-15 (F-15EX) and continuously evolve the F-16, which again is probably a testimony to the Fighter Mafia in itself.
As emphasised by:
"The United States Air Force announced the need for a new multi-use fighter jet to replace its aging F-16 fleet, while stressing that it would not feature the same high-price tag and technological prowess of the F-35.".
Ironically, one could almost say this program of necessity is what the Fighter Mafia saw and did with the LWF(ACF) and NACF programs, as a consequence of the F-15 and F-14 spiralling costs and technological problems.
Personally, I don't think the USAF and USN really know what it wants Vs what it needs and can afford.

Regards
Pioneer
 
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