NGAD / F/A-XX - General Discussion and Speculation

[quellish]

So, you're arguing that the J-20 isn't a "stealth" aircraft?

I guess we have 2010 again.

But on a different note, how does this relate to the topic at hand? Shouldn't this go into the J-20 thread? I brought the aircraft up as it served as an example of a jet with canards which design aimed for a significant reduction of it's signature for radar. You continued because...?

It’s very relevant.

There is:

Reduced Observables

Low Observable

Very Low Observable

Extreme Low Observable

Each of these encompasses a specific range of signature values. Some or all of them might be called “stealth”. The actual values used for each by the US DoD are considered sensitive.

Comparing a LO aircraft to a VLO aircraft, or just calling them both “stealth” makes little sense I see people do it all the time. The F-18E has signature reduction measures applied. Does that mean it should be compared to the F-117 as “stealth”?

 

[Seragina]

Looks like this is just unnecessary nitpicking on details that don't matter for most people's random conversations. We can discern stealth evaluation or classification into two general groups:

1. If it has feature that reduces its radar signature compared to a version without then it qualifies as being stealthy. Example being the SR-71. This would be what most people refer to without any deeper thought.

2. Would be detailed technical classification for the level of stealth as outlined by quellish which would also be useful for radar design. I don't think most people care but still will throw around with a similar mindset as in 1. But alas I suppose plenty would like to go into detailed discussion here.

 

[quellish]

Looks like this is just unnecessary nitpicking on details that don't matter for most people's random conversations. We can discern stealth evaluation or classification into two general groups:

1. If it has feature that reduces its radar signature compared to a version without then it qualifies as being stealthy. Example being the SR-71. This would be what most people refer to without any deeper thought.

2. Would be detailed technical classification for the level of stealth as outlined by quellish which would also be useful for radar design. I don't think most people care but still will throw around with a similar mindset as in 1. But alas I suppose plenty would like to go into detailed discussion here.

Well that is just the problem here.
Details and technical discussions should be why you're here.

If you are looking for fanboy "it has serrations, therefor it is stealth" discussions there are thousands of other sites on the internet that cater to that. SPF is not one of those sites. Historically this has been a place for deeper discussion and research - that is what makes SPF valuable.

 

[Tomboy]

If you are looking for fanboy "it has serrations, therefor it is stealth" discussions there are thousands of other sites on the internet that cater to that. SPF is not one of those sites. Historically this has been a place for deeper discussion and research - that is what makes SPF valuable.

J-20 has a lot more than serrations buddy

 

[Training_Dummy]

Putting the pieces together, Boeing’s AII-X likely demonstrated:

- Novel control effectors leading to lower observability and
- probably tailless supersonic flight, potentially supercruise, maybe even at a higher speed than F-22
- enhanced power generation
- rapid manufacturing using mass production
- AESA or other sensors integral to parts of the airframe structure
- a freaking laser

 

[Seragina]

Well that is just the problem here.
Details and technical discussions should be why you're here.

If you are looking for fanboy "it has serrations, therefor it is stealth" discussions there are thousands of other sites on the internet that cater to that. SPF is not one of those sites. Historically this has been a place for deeper discussion and research - that is what makes SPF valuable.

Perhaps the forum should create more separation & thematically specific threads for each topic like:
1. News only
2. Program speculation & discussion only
3. technical speculation & discussion only
4. artists speculation & discussion only
That might work better and more obvious where things should be going, but frankly, diversions will always happen.
Since we are at it introduce title tags, too, that create consistancy: like "title [News]"

 

[Seragina]

Putting the pieces together, Boeing’s AII-X likely demonstrated:

- Novel control effectors leading to lower observability and
- probably tailless supersonic flight, potentially supercruise, maybe even at a higher speed than F-22
- enhanced power generation
- rapid manufacturing using mass production
- AESA or other sensors integral to parts of the airframe structure
- a freaking laser

I think the USAF was more concerned about performance and the aircraft engineering/design/subsystems as a whole was done within the new open framework the military wanted to have.
The demonstrators weren't completed final designs so they only have to show they have the key points of interest addressed or included to some useful extend.

 

[Hydroman]

Well that is just the problem here.
Details and technical discussions should be why you're here.

If you are looking for fanboy "it has serrations, therefor it is stealth" discussions there are thousands of other sites on the internet that cater to that. SPF is not one of those sites. Historically this has been a place for deeper discussion and research - that is what makes SPF valuable.

True quellish, example, Tacit Blue, B-2 and B-21 all designed for VLO across a wide frequency range (hence shaping, materials and coating evolution). I would assume some level of active signature management as well which has evolved as well throughout the years.

 

[quellish]

I think the USAF was more concerned about performance and the aircraft engineering/design/subsystems as a whole was done within the new open framework the military wanted to have.
The demonstrators weren't completed final designs so they only have to show they have the key points of interest addressed or included to some useful extend.

There were 5 key technologies to be demonstrated.
Boeing did well on those 5 and others that were mostly gravy to DoD.

Mmmm. Delicious gravy.
There are posts within this thread that touch on this gravy. Good luck finding them within all the toxic fanboy speculation!

 

[quellish]

J-20 has a lot more than serrations buddy

Mmmmmk. This is the last discussion of stealth and this specific program i will ever have on this forum, including documents. Not worth my time.

If anyone asks for photos, documents, references, or opinions referencing any of these things I will just point them here.

 

[Scott Kenny]

That is a fair question. F-47 powered by interim F119 engines would be unlikely be able to provide the full avionics cooling required for full mission capability. Based on the NGAD engine size discussion, F119s would probably be able to demonstrate the airframe flight envelope on flight sciences test aircraft, but would be doubtful as interim engines for early production aircraft or even production representative test aircraft. You do have two engines with HPC discharge bleed capability (possibly twice current Single engine F135 bleed flow), but would be unlikely be able to fit fan duct ECS coolers like the F135 and wouldn’t be able to simulate the third stream duct cooling potential.

I'm honestly expecting EMD F-47s to be powered by F110-GE-132s, not F119s. Well, except for whichever test airframes get to do the supercruise tests. Those would get F119s.

Assuming a situation like the OG F-14A, -B setup, where the first ~70 airframes have the interim engines and then the rest of production gets the actual intended engines, then the -C adds some new avionics and capabilities, etc...

It’s very relevant.

There is:

Reduced Observables

Low Observable

Very Low Observable

Extreme Low Observable

Each of these encompasses a specific range of signature values. Some or all of them might be called “stealth”. The actual values used for each by the US DoD are considered sensitive.

Comparing a LO aircraft to a VLO aircraft, or just calling them both “stealth” makes little sense I see people do it all the time. The F-18E has signature reduction measures applied. Does that mean it should be compared to the F-117 as “stealth”?

Well, since I doubt you're going to reply after your last post, I'm going to park some aircraft where I think they fit and let the forum argue about it.

RO: SR-71, Super Hornet, Rafale
big jump
LO: F-117
another big jump, and I feel F-35 is probably here, not in VLO
VLO: F-22, TACIT BLUE, B-2
not as big a jump as between LO and VLO
ELO: Maybe the B-21? B-21 is either here or in the "gap" between VLO and ELO.

I'm expecting FAXX and F-47 to land in VLO, maybe in the gap between VLO and ELO if the definition is narrow enough. I am expecting at least F-22 levels of RCS for FAXX and F-47, if not an order of magnitude smaller RCS. Yes, I'm aware that would make the F-47 or FAXX RCS about the size of a mosquito. If someone was being really cheeky, we'd use that name even though BAe picked up the remains of De Haviland.

 

[sublight_]

RO: SR-71, Super Hornet, Rafale
big jump
LO: F-117
another big jump, and I feel F-35 is probably here, not in VLO
VLO: F-22, TACIT BLUE, B-2
not as big a jump as between LO and VLO
ELO: Maybe the B-21? B-21 is either here or in the "gap" between VLO and ELO.

You can see B-21 on VHF.

 

[Seragina]

big jump
LO: F-117
another big jump, and I feel F-35 is probably here, not in VLO
VLO: F-22, TACIT BLUE, B-2
not as big a jump as between LO and VLO
ELO: Maybe the B-21? B-21 is either here or in the "gap" between VLO and ELO.

This is not about how much of a fraction is being returned but the total amount returned.
So if two designs ends up returning as much energy as an equivalent sized RCS area then both get the same rating regardless. Even if one of them is acutally phsically much larger than the other and returns a much smaller fraction.

 

[overscan (PaulMM)]

It’s very relevant.

There is:

Reduced Observables

Low Observable

Very Low Observable

Extreme Low Observable

Each of these encompasses a specific range of signature values. Some or all of them might be called “stealth”. The actual values used for each by the US DoD are considered sensitive.

Comparing a LO aircraft to a VLO aircraft, or just calling them both “stealth” makes little sense I see people do it all the time. The F-18E has signature reduction measures applied. Does that mean it should be compared to the F-117 as “stealth”?

For the sake of discussions, even if the real range of values is sensitive and unknown, we would need some ballpark ideas.

The values here are my guesses only.

Reduced Observables
>0.5 m² (or one order of magnitude reduction in RCS)
B-1, AGM-86
Low Observable < 0.05 m²
Storm Shadow
Very Low Observable < 0.005 m²
F-117, F-35, F-22, B-2
Extreme Low Observable < 0.0005 m²
B-21

 

[Scott Kenny]

This is not about how much of a fraction is being returned but the total amount returned.
So if two designs ends up returning as much energy as an equivalent sized RCS area then both get the same rating regardless. Even if one of them is acutally phsically much larger than the other and returns a much smaller fraction.

Correct.

I'm saying that F-22, TACIT BLUE, and B-2 all have about the same RCS area, that F-35 is bigger than those, and B-21 is smaller.

 

[sublight_]

For the sake of discussions, even if the real range of values is sensitive and unknown, we would need some ballpark ideas.

The values here are my guesses only.

Reduced Observables
>0.5 m² (or one order of magnitude reduction in RCS)
B-1, AGM-86
Low Observable < 0.05 m²
Storm Shadow
Very Low Observable < 0.005 m²
F-117, F-35, F-22, B-2
Extreme Low Observable < 0.0005 m²
B-21

If the categories include multiple spectrums then B-21 is not going to be in the extreme category.

 

[Ainen]

You can see B-21 on VHF.

If the categories include multiple spectrums then B-21 is not going to be in the extreme category.

This is kind of statement that ideally requires some basis. Not specific documents (we're not on warthunder forum), but either studies or at least explanation.

 

[F119Doctor]

Since the B-21 is a larger airframe, it should be better in the lower frequencies than fighter / attack airframes like the F-117, F-22, and F-35. Smaller airframes are inherently more detectable by lower RF frequencies, which are very difficult to use for precise detection and beginning a kill chain anyway

 

[donnage99]

Correct.

I'm saying that F-22, TACIT BLUE, and B-2 all have about the same RCS area, that F-35 is bigger than those, and B-21 is smaller.

The RCS of f-35 is better than f-22 in certain aspects (could be angles or/and frequencies) and worse in some other aspects. That in no way implies a false equivalence that both are equal in stealthiness. Maybe it's all political BS. But officials at different time during the f-22 vs f-35 budget war both claimed that f-22 was stealthier and that f-35 was stealthier. I'm guessing they were all half truths and oversimplification of the word "stealthier". F-35 was probably better in some regards and vice versa. It depended on what your political agenda was at the time to claim one way or another

Remember F-22 stealth was not emphasized against ground radars as much, a point Boeing guys emphasized during their pitch of A/F-X. The aft section of Boeing A/F-X pitch was supposed to be stealthier

 

[overscan (PaulMM)]

If the categories include multiple spectrums then B-21 is not going to be in the extreme category.

You have no idea what the B-21 RCS will be in VHF band. Northrops XST design was something 100 times lower VHF RCS than Lockheeds XST (which is why they got given TACIT BLUE) The idea that long wavelength radars can easily detect all stealth aircraft rests on the assumption they are all working like the F-117 did.

 

[quellish]

You have no idea what the B-21 RCS will be in VHF band. Northrops XST design was something 100 times lower VHF RCS than Lockheeds XST (which is why they got given TACIT BLUE) The idea that long wavelength radars can easily detect all stealth aircraft rests on the assumption they are all working like the F-117 did.

It also assumes they are fighter sized.
A large aircraft has more opportunities for signature reduction in lower bands.

 

[sublight_]

You have no idea what the B-21 RCS will be in VHF band. Northrops XST design was something 100 times lower VHF RCS than Lockheeds XST (which is why they got given TACIT BLUE) The idea that long wavelength radars can easily detect all stealth aircraft rests on the assumption they are all working like the F-117 did.

Whats the wing chord of the B-21? I am sure they'll be able to notice it in the lower VHF bands. And when I say multi spectrum I am talking about the inclusion of IR and UV. If the "extreme" category doesn't include these, then there is a further "unmentionable" category.

 

[quellish]

Whats the wing chord of the B-21? I am sure they'll be able to notice it in the lower VHF bands. And when I say multi spectrum I am talking about the inclusion of IR and UV. If the "extreme" category doesn't include these, then there is a further "unmentionable" category.

 

[donnage99]

If the categories include multiple spectrums then B-21 is not going to be in the extreme category.

I can't imagine your disappointment when Northrop did a full brief of all the classified and propriety stealth advancements in IR and "lower VHF bands" the last quarter of a century since the B-2.

 

[yeetmahboi]

You can see B-21 on VHF.

You can see anything with a radar, duh. It's material, it's there. It's the processing system that has to contend with what the flip is that blip doing.

 

[sublight_]

I can't imagine your disappointment when Northrop did a full brief of all the classified and propriety stealth advancements in IR and "lower VHF bands" the last quarter of a century since the B-2.

We're pretending multistatic passive sensors don't exist? Ok, cool.

 

[Seragina]

Lets get into the science. It's frankly, pretty basic and no real complex math involved. Only some minor conversions and rewritting are necesssary. So here's my two cents.

Well, based on scattering the smaller the ratio of body-size to wavelength the larger the gab between signal maxima and minimum, hence, it becomes possible to finetune for a lower return:
(quick and dirty edit of a wavelength scattering plot with additional notes; for a better one see RCS at wikipedia)


Since Decibel is a logarithmic 10 scale (similar to Richter scale) the calculations are a bit different. But it's still a scale so it's "easy" to allocate the areas:


The "Reduced Observable" range is rather open to arbitrariness due to narrowness and proximity to today's convential dessign.
It's the wave bands that's troublesome with scalealignment and where it becomes a more nuanced technicality.

 

[donnage99]

We're pretending multistatic passive sensors don't exist? Ok, cool.

Ok let me fix my original statement for you:

"I can't imagine your disappointment when Northrop did a full brief of all the classified and propriety stealth advancements in IR, "lower VHF bands", and against multistatic passive sensors the last quarter of a century since the B-2."

What else would you like to add?

 

[EmoBirb]

I think we kinda lost sight of the thread topic.

Isn't there general stealth thread where this stuff would be more useful and in the proper place?

 

[insidersource]

Some speculation and questions for the members here.

What level of commonality do people expect between the F-47A and F-47B?

Do you think the the Navy aircraft will have a larger wing like the F-35C or will it be like the Rafale with a shared wing?

Do you think they will have the same size weapon bay?

What will the engine options look like? Will the USAF have a high cost, high performance and high maintenance engine and the Navy has a low cost, low performance and low maintenance engine?

My thoughts.
The F135 engine costs around $20 million each. The XA102 and XA103 for the USAF aircraft might cost $30 million each and push close to 40,000lb of thrust. A 2000 hour TBO seems reasonable due to the extreme performance. The USAF then selects one winner out of the XA102 and XA103.

The F110 engine costs around $8 million each
The conventional engine for the Navy might cost $10 million each. Based off the existing F100 and F110 family and push closer to 35,000lb thrust. 6000+ hour TBO due to the Navy durability requirement. The Navy picks one winner out of the evolved F100 and F110.

This would allow the same shared airframe to meet both USAF and Navy requirement. The flyaway cost of the Navy aircraft then costs $40 million less just from the engines. The 6000+ hour TBO of the Navy ngines significantly reduce the Navy's operational costs compared to the USAF variant. The Navy needs 500-600 aircraft to replace the Super Hornet.

This following question would now be getting asked. Would it be better to keep both the XA102 and XA103 as the only engine options for both services? The competition could reduce the engine cost and improvement reliability. Let's say this allows the cost to come down from $30 million to $20 million due to increased production rate. Lets say the time between overhauls goes up from 2,000 hours to 4,000 hours. The Navy gets a significant performance boost for a small cost increase. The USAF gets a significant cost saving while keeping the same performance.

I'm leaning towards the Navy getting an adaptive engine for the F-47B despite all the years of saying otherwise.

 

[quellish]

Some speculation and questions for the members here.

What level of commonality do people expect between the F-47A and F-47B?

Zero. There is no F-47B.

You keep posting as if the Air Force NGAD and Navy F/A-XX are the same or closely related… then talk about how different they are.

The Navy program is very, very different than the Air Force program. For example, the Air Force program is very dependent on other components the Navy does not have.


There are components of the NGAD family of systems that are quite mature and advanced today that the forum and “aviation media” have not discussed. Because the “aviation media” repeats the forum, and the forum has been repeating the “aviation media”.

 

[Seragina]

They are supposely modular, assuming they can exhange core fuselage and wings for future iterations. So there could be any number of combination. But ultimately and for convenience they probably will be differentiated by visible wing planform.

 

[Reddington777]

Relevant to this discussion is this tidbit from an USAF brochure talking about the future vision for NGAD from 2016:

"As the pace of technological advancements continue to increase the Air Force must
leverage experimentation and prototyping to more rapidly infuse advanced technologies into the
force. Additionally, the Air Force must reject thinking focused on “next generation” platforms.
Such focus often creates a desire to push technology limits within the confines of a formal pro-
gram. Such efforts should be accomplished within the S&T portfolio and proven through effec-
tive prototyping, harvesting when mature to a sufficient level for transition. Pushing those limits
in a formal program increases risk to unacceptable levels, resulting in cost growth and schedule
slips. This put such programs at risk of cancellation due to their nearly inevitable underperfor-
mance, and results in delivery of capabilities “late to need” by years or even decades."

It's doubtful to me that the F-47 is going to have variants until the changes made to it are at a "sufficient level for transition". In the future, we ought to start doing away with the whole idea of "a new variant for a new tech package". Instead, most of the upgrades and changes to the aircraft may or may not even be visible on the outside anymore unless it's a planform change.

 

[Scott Kenny]

Some speculation and questions for the members here.

What level of commonality do people expect between the F-47A and F-47B?

Do you think the the Navy aircraft will have a larger wing like the F-35C or will it be like the Rafale with a shared wing?

Do you think they will have the same size weapon bay?

You're thinking that both USAF and USN will be flying F-47, like how there's F-35A and -C?

No. The program requirements are not compatible.

USAF wants a replacement Raptor. Heavy on the air-to-air capabilities, with whatever air-to-ground physically fits in the bays a pleasant bonus (1000lb JDAM has the same "box size" as an AMRAAM-C). I doubt the F-47 is spec'ed to be capable of taking 2000lb ordnance or B61 nukes. I'd hope it is spec'ed to carry 14ft long and 20" square weapons (ie, 2000lb size), but I doubt that it is. While the USN wants a long range stealthy strike fighter, which means significantly deeper and longer bays than the F-22 has, and/or much more fuel than an F-35C.

The USN has landing approach speed limits that the USAF does not have (at all).

The USN is also willing to accept somewhat lesser stealth in exchange for carrier compatibility, while the USAF has been pushing for the most stealth they can get since the 1970s.

It's doubtful to me that the F-47 is going to have variants until the changes made to it are at a "sufficient level for transition". In the future, we ought to start doing away with the whole idea of "a new variant for a new tech package". Instead, most of the upgrades and changes to the aircraft may or may not even be visible on the outside anymore unless it's a planform change.

Not to mention that a lot of what used to be version differences due to completely new radars etc are going to be able to be software updates.

 

[insidersource]

You're thinking that both USAF and USN will be flying F-47, like how there's F-35A and -C?

Yes, or even better like the Rafale C and M.

No. The program requirements are not compatible.

Do you know the requirements? Do you think they have vastly different combat radius?

While the USN wants a long range stealthy strike fighter, which means significantly deeper and longer bays than the F-22 has, and/or much more fuel than an F-35C.

So you are saying the USAF aircraft will need smaller weapon bays compared to the Navy aircraft? It is worth noting the F-35B has smaller weapons than the other family members.

Why do you think the weapon bay size differences could be achieved with a design with very high commonality?

The B-1B usually carries a fuel tank in one of its three weapon bays because it usually doesn't need such large payload volume. There are plenty of ways to trade payload volume for extra fuel.

The USN has landing approach speed limits that the USAF does not have (at all).

We see the USAF F-47 rendering showing canards. The Rafale has proven that a delta canard design can supercruise and still have a lower landing approach speed for the carrier. The Rafale doesn't even need to increase the wing area for the carrier version unlike the F-35C. The Rafale manages modest supercruise with a lower thrust to weight and lower tech engines compared to the F-22. The high output XA102/XA103 engines and slightly reduced weight of a land based version will provide great supercruise performance in a shared design.

Aerodynamics have improved significantly over the last few decades.

The USN is also willing to accept somewhat lesser stealth in exchange for carrier compatibility, while the USAF has been pushing for the most stealth they can get since the 1970s.

The Navy can perform a reduced maintenance schedule on the stealth coatings. They then get lesser stealth at lower maintenance cost. The same basic design can then be shared.

 

[Q-nimbus]

https://www.dreamlandresort.com/area51/groom_photos_2025-08.html

There are some new incredibly detailed photos of Groom Lake courtesy of our friends at Dreamland Resort.

What was of particular interest to me is that you can clearly see two F18’s under a shelter.

Now why would the Navy be present at Groom Lake…

 

[dark sidius]

Is it a sign of FA/XX demonstrators flying at Groom ?

 

[Reddington777]

You're thinking that both USAF and USN will be flying F-47, like how there's F-35A and -C?

Yes, or even better like the Rafale C and M.

No. The program requirements are not compatible.

Do you know the requirements?

JFC. You just won't let this idea go. Forgive me for sounding rude but you really do embody your username to the max - your source is just inside your own head. That's it.

If you are going to question other people, then provide your own, non-cherry picked sources that don't conflict with each other. Not just a disney level of fairy tale weaving with conjectures that run headlong against literally all the reporting that's been made with regards tot he two programs. It's gotten to the point that I feel like I'm reading elden ring fan theories.

Let me answer your conjectures with the words of Admiral Cheever's interview with CSIS only 11 days ago:

00:20:20 Interviewer:
...Um what do you see as the most critical requirements for the sixth generation fighter for the Navy? And then do you envision that um we're gonna you may not know maybe still too early to tell but um an approach similar to what we did with the F-35 where you know the Air Force and the Navy and the Marine Corps all have derivatives of that aircraft or do you see going a totally different direction for the sixth generation fighter for the -

00:20:49 Adm. Cheever:
...Yeah I think for sixth generation I see a maritime version of the aircraft that's that starts at the carrier is made for the carrier and is a complete carrier version. Uh and then I uh it will be uh replacing both the Super Hornet and the Growler.

In case Cheever's word mincing is still lost on you - he is referring to "version" in reference to sixth generation. If it were a derivative, why doesn't he just say "yes it is" ???????????????????????????????????

And like I said in the huge post in the other thread - the navy has repeatedly, publicly emphasized that the F/A-XX has nothing to do with the F-47 be it engines, roles, or for the political purpose of keeping the program. With the information we know right now, everything points to a separate aircraft. Not a derivative.

Even if you turn out to be right in the future, absolutely no one owns you an apology either, because at this point in time, drawing the conclusions you want to draw with the information publicly available makes damn near zero sense.

 

[quellish]

Now why would the Navy be present at Groom Lake…

Why wouldn’t they be? It’s a national facility. They also have a presence at TTR, which is currently closed.

 

[Scott Kenny]

Yes, or even better like the Rafale C and M.

That's what I thought.

Do you know the requirements? Do you think they have vastly different combat radius?

To some degree. Look at the program names to start with. Next Generation Air Dominance versus Fighter/Attack-XX. Now look at what aircraft are being replaced. F-15C/Ds and F-18E/F/Gs.

USAF was also talking about basing beyond the second island chain, which means a combat radius over 1000nmi/1900km.

So you are saying the USAF aircraft will need smaller weapon bays compared to the Navy aircraft?

Not "need" so much as "does not have a requirement for" the larger weapons bays of the Navy aircraft.

I'd hope that either Boeing or USAF would have left bay volume for packing a large number of bombs as a "Strike NGAD" to replace the Strike Eagle because otherwise you replace the Strike Eagles with B-21s.

Why do you think the weapon bay size differences could be achieved with a design with very high commonality?

An airframe like the Su57, with either 1 super-long bay or 2 separate bays, would allow for carrying what I expect the USN to be requiring without needing a super wide weapons bay section. (I'm assuming the same weapons load requirements as the old ATA A-12 Avenger.)

Whereas the USAF requirements could probably be handled by stretching the bay section of an F-22 by 2 feet.

We see the USAF F-47 rendering showing canards. The Rafale has proven that a delta canard design can supercruise and still have a lower landing approach speed for the carrier. The Rafale doesn't even need to increase the wing area for the carrier version unlike the F-35C. The Rafale manages modest supercruise with a lower thrust to weight and lower tech engines compared to the F-22. The high output XA102/XA103 engines and slightly reduced weight of a land based version will provide great supercruise performance in a shared design.

I strongly suspect that the only shared features of the two designs are avionics and maybe control surface actuators.

The Navy can perform a reduced maintenance schedule on the stealth coatings. They then get lesser stealth at lower maintenance cost. The same basic design can then be shared.

That's not at all how that works.