Multi-Role fighter (MR-X) F-16 Replacement ("4.5 Generation Fighter")

As they´re thinking/talking about a clean sheet (4.5 generation) replacement for the F-16, to complement ( = not have to utilize) the F-35 on the (much) less demanding missions where stealth is not required, like in conflicts with (somewhat) 'permissive' airspace and/or the homeland defense mission, something like a KF-21 (first block) pops to my mind.
They don´t want the operating and maintenance costs that come with the (stealth-requirements of) the F-35 , but certainly they still want advanced radar, sensors, awareness, weapons, etc. When you then decide not to go forward with the latest/new variants of existing designs (because those have no or not enough open architecture or can´t be updated enough to what you really want) and you decide to proceed with a clean sheet design, you might want one which doesn´t have the advanced skin and/or coatings and internal weapons-bay of the F-35 but you might still want to make use of the opportunity to have a reasonable degree of stealth-shaping incorporated into your new design, just for in case you´d later want or would need to upgrade the result of your clean sheet design for use in scenarios/operations/conflicts which you didn´t have in mind at first.
So you might want to go with something alike a 'KF-21' design, which does not come with the extravagant costs of an F-35 but which nevertheless offers the option to change it into a more advanced version (with e.g. an internal weapons bay and possibly other enhancements) over a relatively short time-period without having to start from scratch again. Unless you have nothing much more then something like Irak/Afghanistan-conflicts and air-policing scenarios in mind, then I guess something resembling a 'Boeing/Saab F-7' would do just fine.
Just my 2 cents.
 
ALIS (or rather some kind of prognostic maintenance system) is something you'll want to keep, you just need to have it executed better, ideally by it being a repeatedly competed system that the government owns the rights to.

As for DAS; while there'd be room for cost and schedule savings by not having the F-35 DAS's fancier software features, I don't think you'd save much money by making the sensors themselves less capable, particularly with how IIR sensors are trending lower in cost and reduced cooling requirements. It'd also be nice to have the fancier DAS functions available as a software-only growth option.
My point rather comes down to having less complex architecture, especially on the software side of things. My opinion is rather concerning the risk management of the development program, as avoiding those aforementioned/avionics of equivalent complexity would probably mean less debugging process. A conventional MAWS in that sense is way more simpler in terms of its architecture compared to the DAS which is deeply rooted and integrated to the CNI and EW suite of the F-35 capability-wise.

(not sure what you're referring with IWB though - are you talking about the wing being integral to the fuselage?)
Internal weapons bay;)

The F414 might not have much life left by the time an MR-X is procured;
Still, SH will fly for decades to come when the MR-X is going to be introduced (early-mid 30's) and there are other foreign aircraft like Gripen E. KF-21, Indian MWF and AMCA Block 1 which would use the F414 so I'm not really concerned about its service and maintenance constraints. Though yeah, I was not aware that the F135 was already down-rated. In that case, using a single F135 would provide sufficient thrust + would be less maintenance cost and more efficient as well.

It's not cheap enough; I'm also not sure it offers the same level of open architecture avionics as the USAF is interested in pursuing (though you could always retrofit such a capability). When the USAF talks about the MR-X being cheap, they're talking about how in 2018, Mattis set an 'affordability constraint' on the USAF that apparently requires the USAF F-35A fleet in 2036 (it's a kind of baseline year for this affordability analysis) to cost $4.1 million per tail, per year (https://www.gao.gov/products/gao-21-505t).

I'm not sure why they set that figure as the requirement, but if we use the 250 flight hours per year that the Pentagon uses in their sustainment cost estimates, that works out to a required CPFH of $16,400. I don't have CPFH figures for the Super Hornet (there are reimbursable CPFH figures, but they're not comparable in this context), but if an F-16C/D costs ~25k/hr and Boeing was advertising the F-15EX's low sustainment costs at $28k/hr, I don't think a Super Hornet is going to reach the $16.4k/hr constraint, let alone be far enough below that to offset the F-35A's CPFH.
Whoa, that's quite some requirement if it really is the case. I would rather agree with your points of it being misunderstood or understood correctly but will be removed. I will lean towards the latter. In terms of the open architecture, I would really like to know what this core difference between the MR-X and redesigned legacy fighters would be. Limitations in Plug-and-Play and OFP updates on the fly comes into my mind, although I'm not sure if that's completely impossible to implement on the legacy fighter jets.
 
Yes. Unless the KF-21 happens to have more extravagant ownership costs. :rolleyes:

Well, I used the term 'extravagant' costs mostly with the missions they apparently envisage for their clean sheet F-16 replacement in mind.
I can´t see a less advanced 'KF-21 block 1 style' medium-sized design costing more to the USAF to buy, operate and maintain (in such missions) then an F-35, unless the design and/or the program is flawed and/or if they end up only buying 'a handful'.
If cost difference with F-35 (for such missions) would be thought to be minimal, I assume they woudn´t be thinking about starting a clean sheet non-stealth optimized design and to use/keep the F-35´s mostly for missions into highly contested airspace.
Of course a whole new design program has it own (big) costs, but there must be some good reason they are (seriously) considering starting a clean sheet. The cost of the start of a(nother) complete new program (in about 8 years or so), is one reason I´m also thinking about the possibility of something like (not much more then) a 'clean sheet' F(T)-7 low-cost fighter.

What the actual KAI KF-21 (program) in Korean hands will end up costing, is another matter.
 
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Something I (almost) forgot:
Potential for future US export of such a clean sheet F-16 replacement to countries who can´t afford (enough) F-35´s, who want to complement their F-35s with another still (optionally-)manned fighter (here too for lower demanding missions), or who don´t need F-35´s (or future Tempest´s & FCAS´s). NGAD most probably won´t be exported and I can imagine the same for F/A-XX, so what (very fresh thing) would otherwise be left for US-export starting in the 2030s on the (optionally-)manned fighter market besides F-35 and F-15EX ...
 
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Yes that's a big part of the problem, the receding effect: US allies that are not committed to the F-35 effort are left without any ideal solution from the US post F-16.
When I look at the T-7 program, that bears many similarities, I wonder if there isn't a solution there.
 
My point rather comes down to having less complex architecture, especially on the software side of things. My opinion is rather concerning the risk management of the development program, as avoiding those aforementioned/avionics of equivalent complexity would probably mean less debugging process. A conventional MAWS in that sense is way more simpler in terms of its architecture compared to the DAS which is deeply rooted and integrated to the CNI and EW suite of the F-35 capability-wise.
It'd be worth noting that the F-35's mission systems integration isn't too bad; it definitely could have been done more cleanly, but they did do some very good things like make the sensor fusion system (which is then what weapons targeting, EW, etc primarily draws from, rather than individual systems) sensor agnostic. So long as sensors output data of some "VSIM" standard, the fusion system will work with them. That standard is Lockheed proprietary though to my knowledge, so it'd be nicer if the likes of DARPA and the services were able to establish something more universal with sufficient breadth / flexibility to match proprietary solutions. And of course besides the sensor fusion, the sensors like DAS do also have to output video to the HMDS system, PCD electronic units, etc (likely via the ICP); they also have some programming of their own like the "You Are The One" algorithm that determines if you're the target of a missile launch (that probably runs on the ICP and is then output to the ASQ-239, etc).
Internal weapons bay
Ah, obvious in hindsight; and yeah I don't think an IWB would be a good choice for a low-cost platforms.
Still, SH will fly for decades to come when the MR-X is going to be introduced (early-mid 30's) and there are other foreign aircraft like Gripen E. KF-21, Indian MWF and AMCA Block 1 which would use the F414
I wasn't aware that the latter 2 were planning on using the F414 (also forgot at the time the KF-21 was planning to use them). Between the Gripen E, KF-21 and MR-X it'd probably be a viable engine, but yeah, a single engine might be best for low-cost. Depending on how big of a jet and how low-cost we're talking, a single F414 might do the job. I'm not sure the F135 would be viable past the 2030s as while the B-21 might use some F135-related engine, and some F-35 users might not transition to adaptive cycle engines, I wouldn't expect F135 production to last long enough.
In terms of the open architecture, I would really like to know what this core difference between the MR-X and redesigned legacy fighters would be. Limitations in Plug-and-Play and OFP updates on the fly comes into my mind, although I'm not sure if that's completely impossible to implement on the legacy fighter jets.
From an avionics perspective the only real difference between a clean sheet MR-X and an overhauled legacy fighter with regards to achieving open architectures would just be to do with SWAP; you have more options for avionics if you design a jet to have better electrical and thermal capacity, both of which can be problematic to retrofit into a small airframe like the F-16 (without grafting on things like dorsal spines, etc that decrease performance) and can complicate maintenance. There could also potentially be intellectual property rights issues with certain airframes if any past contracts made the jet's manufacturer (or the current 'caretaker' company) the sole entity responsible for systems integration, whereas with a clean sheet you can write new contracts that increase competition opportunities by signing certain rights over to the Pentagon.
Otherwise with either clean sheet / legacy design, the idea is to create a system that's as modular as possible, allowing for sensors to be more plug & play without also having to sacrifice things like high-end sensor fusion, etc. That way sensors, EW systems, displays, core processors, etc can all be competitively chosen and integrated with a smaller budget and tighter schedule. There's a been a number of jets with "open architecture" systems in the past, but they've generally come with considerable caveats. The F-22 for example was advertised as having an "open systems architecture", but from what I've heard from people that've worked with it, the F-22's sensor fusion system is far more intertwined and hard to add new sensors to than the F-35's.
 
Yes that's a big part of the problem, the receding effect: US allies that are not committed to the F-35 effort are left without any ideal solution from the US post F-16.
When I look at the T-7 program, that bears many similarities, I wonder if there isn't a solution there.

In the 60's a choice existed between F-104G, Phantom and F-5.

In the 80's: F-15, F-16, F-18 (and even F-20, and Iran got Tomcats, too)

Nowadays: F-35, F-35, F-35 and F-35...
 
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Yes that's a big part of the problem, the receding effect: US allies that are not committed to the F-35 effort are left without any ideal solution from the US post F-16.
When I look at the T-7 program, that bears many similarities, I wonder if there isn't a solution there.

In the 60's a choice existed between F-104G, Phantom and F-5.

In the 80's: F-15, F-16, F-18 (and even F-20)

Nowadays: F-35, F-35, F-35 and F-35...

The F35 over-promised and under-delivered.

What the Air Force is saying is they cannot afford to operate as many F35s as they project they will need.

Either the cost of operating the F35 needs to come down or they will need to buy a different aircraft that they can afford to operate in the required numbers.
 
The price will only come down when numbers are higher if memory serves correctly.
 
The price will only come down when numbers are higher if memory serves correctly.
Yeah, I think the AF should and would at least wait for the FRP to come through and see how it affects other costs. Question is, if the FRP would be delayed any further?
 
The F35 has taken the US back to the early 1970s when the F4 Phantom had become the dominant fighter bomber type for the USAF, USN and Marines.
The F15 and F14 were arriving as "hi-end" fighters. By the 1980s they had been joined by far greater numbers of F16s.
The F18 was developed into a replacement for F4, A7 and then in the 90s for the A6 and F14.
This suggests that additional types will evolve to supplement the F35 and eventually replace it.
The F22 would have replaced F15s and possibly F14s if the Cold War had continued. The F35 would then have replaced F16s and F18s.
 
Let's say MR-X goes through. Where would they be able to cut corners?
Main things that come to mind
1. Agility: In the future air combat environment with 15G+ drones, missiles and other weapons will be designed to hit targets of that performance range. The need for energy to maneuver, the air frame strength and aerodynamics means a meaningful defensive advantage from this is going to be very expensive and be fairly marginal in effectiveness.
2. Radar: With mixed formations there is no need for the entire fleet to have high performance radar able to search for 5th and 6th gen aircraft at effective ranges.

Some other thoughts
3. One can probably move payload and most openings to the top of the aircraft to enable VLO against ground radars while being cheap. Weapons release would be: do a barrel roll ;D

Ultimately I don't think a cut cost aircraft can compete air to air fully against a 5/6th gen, and the primary mission this class of airframe will be ground attack and conduct air combat only when using combined arms tactics.

----
Though this is ignoring the general change in combat environment with large scale adaption of tactically relevant UAVs. Just what kind of mission and tactical environment demands a human crew on the airframe, and to do what task exactly?
 
Leaving aside for the moment things like Agile Falcon and NATF, there would have been programs such as the USAF's Multi-Role Fighter, the USN's A/X (or possibly the A/FX if the A-12 program had still collapsed in this timeline), and DARPA/USN's ASTOVL or else potentially the alternative of a revived P.1216 or similar. There might have also still been something like CALF (Common Affordable Lightweight Fighter) in this timeline as well. In our timeline, CALF evolved from ASTOVL.

0227161022a-1-jpg.551402

(h/t XP67_Moonbat)

lockheed-rockwell-afxstealthattack-jpg.18545

(h/t Rafael)

mdd-calf-astovl-jpg.84029

(h/t flateric)
 
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Perhaps an F-16 replacement is another F-16?

Like the F4 before it, I see no reason why the F16 should not carry on being upgraded and built rather than re-inventing the wheel. It is still better than the Mig 29 and J-10.
 
Perhaps an F-16 replacement is another F-16?

Like the F4 before it, I see no reason why the F16 should not carry on being upgraded and built rather than re-inventing the wheel. It is still better than the Mig 29 and J-10.

I still think that the whole idea behind this is to get LM to make the F-35 cheaper, so threatening to cut the F-35 buy in order to procure a different type doesn't work if that other type is also made by LM . . .

cheers,
robin.
 
Perhaps an F-16 replacement is another F-16?

Like the F4 before it, I see no reason why the F16 should not carry on being upgraded and built rather than re-inventing the wheel. It is still better than the Mig 29 and J-10.

I still think that the whole idea behind this is to get LM to make the F-35 cheaper, so threatening to cut the F-35 buy in order to procure a different type doesn't work if that other type is also made by LM . . .

cheers,
robin.
I thought the thing was that the 35 is too good to bring to the table in a low intensity fight. Again another pearl necklace too expensive to actually wear out and about.
 
Perhaps an F-16 replacement is another F-16?
If they reach their goal of $25k/hr by 2025 for the F-35, it'll be the same or slightly cheaper than the legacy fleet of F-16C/Ds in CPFH. How much a brand new F-16V Block 70/72 costs per flight hour though I have no idea.

Edit: Also the USAF wants its F-35 fleet to reach $4.1m per tail per year; I don't think F-16s would be cheap enough to offset the $6.25m per year that even $25k/hr @ 250hrs/year would result in.
 
The F-35 is already insanely cheap.
It is also a cost saving platform by being able to fly without all the supporting aircrafts required by other airframe.

The problem of cost is ill-defined and the Gao did a poor job not putting that in parallel in their evaluation reports.
 
Perhaps an F-16 replacement is another F-16?

Like the F4 before it, I see no reason why the F16 should not carry on being upgraded and built rather than re-inventing the wheel. It is still better than the Mig 29 and J-10.

In addition to the pressure on Lockheed angle, I see two more compelling reasons to leave the F-16 behind.

First, the US ability to design new airplanes and UAVs depends upon designing new airplanes and UAVs. Keeping with old designs freezes the aerospace industry in a 1980s apart from a few boutique programs that take decades long, etc. Airplane design is an art, not a science, and artists only improve by practice.

Second, it is highly probably that the F-16 does not have the internal power and cooling capability to manage modern electronics. If advanced dual-stream engines become widely available by 2030 timeframe, the MR-X replacement will likely want to use a (possibly de-rated) version of the dual-stream engine to leverage existing R&D.

A possible 4.5 gen is: new (possibly shrunken for NGAD?) GE engine, the best bits of the F-35 combat system, but re-done in a loosely-integrated open architecture, and a modern transonic fighter airframe. Nothing fancy by the standards of 2030, but requiring a new build.
 
The F-35 is already insanely cheap.
It is also a cost saving platform by being able to fly without all the supporting aircrafts required by other airframe.

The problem of cost is ill-defined and the Gao did a poor job not putting that in parallel in their evaluation reports.
F-35 may be cheap to buy given the capabilities it offers, however, it's very expensive to operate per flight hour.
I will be curious to see the difference between the cost to fly an F-35 an F-16 a T-7 Red Hawk for 1 hour.
 
Easy:
1. Live, execute the mission= cheap and sustainable
2. Live (maybe), mission goals often unreachable = unsustainable
3. Die, compromise the mission, endanger rescue forces = where was that 1 trillion $ coin?
 
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The F-35 is already insanely cheap.
It is also a cost saving platform by being able to fly without all the supporting aircrafts required by other airframe.

The problem of cost is ill-defined and the Gao did a poor job not putting that in parallel in their evaluation reports.
F-35 may be cheap to buy given the capabilities it offers, however, it's very expensive to operate per flight hour.
I will be curious to see the difference between the cost to fly an F-35 an F-16 a T-7 Red Hawk for 1 hour.
I wonder how many T-7s and F-16s an S-400 site could shoot down in an hour.
 
I wonder how many T-7s and F-16s an S-400 site could shoot down in an hour.
Assuming a battery has three launchers of six (18 missile) with a 90% function rate then 17 aircraft per hour. If you shoot two missiles per engagement then 8-9 aircraft. The per hour is what gets you. It is not a simple task to reload an S-400. It takes a bit of time (as in more than an hour I suspect).
 
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Assuming a battery has three launchers of six (18 missile) with a 90% function rate then 17 aircraft per hour. If you shoot two missiles per engagement then 8-9 aircraft. The per hour is what gets you. It is not a simple task to reload an S-400. It takes a bit of time (as in more than an hour I suspect).
I think they typically have more like 48 - 64 missiles per battery on 4-round TELs. (Some have more.)
 
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Most of the time when I see S400s set up in satellite shots its four launchers with four tubes, but I think the system is capable of scaling to much larger numbers of launchers and also there are short ranged missiles for S400 that pack four to a tube, like MIM-104 PAC 3. So it would depend the specific arrangement and loading of the battery, as well as reload times. But I think the short answer is "enough to make it too expensive".
 
Assuming a battery has three launchers of six (18 missile) with a 90% function rate then 17 aircraft per hour.
Wat?..

S-400 doesn't have 6 missiles on the launcher, it doesn't typically utilize three TELs per battery and it sure as fuck don't take AN HOUR to reload.
View: https://youtu.be/tRjZBdq4zvk
 
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Some correction...
One battery of S-400 usually consists of 8 TELs, sometimes reinforced by four additional, thus 12 in total.
One S-400 regiment usually has two batteries.
And one regiment usually has two loading vehicles 22T6...

So in total one battery will usually have 32 ready missiles, potentially up to 96 (with four reinforcing TELs dedicated to 9M96). But having only one reloader per 12 vehicles will indeed make full reload cycle a LONG one.
 
MR-F/MR-X effort probably aborted:
The MR-F first showed up in planning documents in 2021 that indicated the Air Force was looking to an F-16 successor in the mid-2030s. The documents suggested the aircraft sought would not be intended as an all-up, very stealthy jet, but what Chief of Staff Gen. Charles Q. Brown Jr. characterized as a “fifth-gen-minus” fighter, for which affordability, and not necessarily high-level survivability, would be a key requirement.

Former head of Air Combat Command retired Gen. James “Mike” Homes suggested that an armed version of the Boeing T-7 trainer could be adapted to such a role and also serve as an export fighter for partner countries lacking the funds or expertise to operate and maintain a more complex aircraft.

But “I have nothing in the mix with requirements from ACC to pursue that,” Bailey said of the MR-F and T-7 derivative.

 
MR-F/MR-X effort probably aborted:
The MR-F first showed up in planning documents in 2021 that indicated the Air Force was looking to an F-16 successor in the mid-2030s. The documents suggested the aircraft sought would not be intended as an all-up, very stealthy jet, but what Chief of Staff Gen. Charles Q. Brown Jr. characterized as a “fifth-gen-minus” fighter, for which affordability, and not necessarily high-level survivability, would be a key requirement.

Former head of Air Combat Command retired Gen. James “Mike” Homes suggested that an armed version of the Boeing T-7 trainer could be adapted to such a role and also serve as an export fighter for partner countries lacking the funds or expertise to operate and maintain a more complex aircraft.

But “I have nothing in the mix with requirements from ACC to pursue that,” Bailey said of the MR-F and T-7 derivative.

It was a concept that was ill-fated from its inception, as a lot of us in the forum argued. It was trying to replae the F-16...with a F-16, kinda. Since they are upgrading 600+ units into C/D Block 70/72, it would be wiser to wait for a F-35 Milestone C, although no one knows when that will come, but probably before 2030. Most importantly, if they've got any funds to spend on a watered down F-35 or a beefed up F-16, better use that fund on NGAD since no MR-F will be of any use in the Indo-Pacific. Especially when they say that even the F-35s are not going be enough in the future.
 
I think any chance that program had of being carried out died after Feb 24th. There's no need for another second tier aircraft; the Pacific theater is the focus.
 
The time to have done a non fifth generation F-16 replacement was the 90s. An upgraded F-16 is more capable then a T-7 upgrade, leave that to the export market.
 
I think the comparison with an armed T-7 is a non sense. The competition should be evaluated as being, the F-35 on one side, and the various 5th Gen like projects like the KFX.

When AMCA, TFX, KFX (and Plan B?) will be fielded in service, what room would be left for a classic F-16? F-16 doesn't have the range, the load out and the speed/performance ratio of an f-15EX.
 

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