Possible configuration of the Boeing F-47 NGAD

[Scott Kenny]

Friendly bet Scott Kenny regarding the F-47:
Combination of NATF-23 and X-36. Maybe not a full diamond wing but blended into the forward, lifting body fuselage, close-coupled canards, no vertical tails, at least three elevons and possibly thrust vectoring, can't wait to see more actual images at some point.

Deal. Loser buys the first round of beverages!

 

[Scott Kenny]

Yes, same here, though I expect the wing to be more delta than lambda to carry fuel for a Pacific range.

I'm leaning more towards B-21 shape, fuel in the inner portion, but delta is possible (see the Chinese).

 

[FlyGuy369]

And that's when we get this

 

[Low IQ Techie]

Actually, they said it's 46 in (1.1684 m) in diameter:

117cm dia. means 17% more wider & higher than F-22's F119,
1.17^2 almost 37% more inlet area, means more air mass flow
& length also increased by 17% then volume/weight would increase by 1.17^3=1.6 or 60% more.
That's like 17% more XYZ scaled up F-22 for a brief idea.

The expectations seems for the new ones for the F47 to be a bit smaller (as in shorter). Intake size might increase a bit, though.
Very likely. Stealth needs to be compact and reduce surface area which also is the same as wet area, hence, less drag.
My take on the rendered design seems to have the cross section area reduced to ~94/95%.

For VCE, a 3rd channel air flow should increase diameter. If outer channel dia. is restricted, so is inner channels, means impact on thrust.

For flight at differnt speeds & altitudes, the area of intake, engine inlet & exhaust are related mathematically, IDK exactly how. Those propulsive efficiency formulas & equations are too much for me to handle.

How can a 6gen jet have :
- more weapons
- more fuel
- more range
- more speed
BUT engines smaller than previous ones?

If you reduce CS by 4-5%, then volume has to be compensated by increasing length, impacting area required for intakes, inlets, as i showed in diagram few pages back.

 

[Seragina]

Why do you say that?

Complexity naturally increases "failure points".

If we are talking only about radiation mitigation. Then it would come down to skin thickness or shielding thickness if you will. That's why the F22 is heavier than the F15 even though volume wise they are close. You would think thicker is better but it's not that simple.
There's a limit to mass attenuation coeffient (absorbtion) that can be achieved and even then scattering can still result in a lensing effect (buildup). Because of that your calculations always end up with an underestimated rate. That's why real world measurement is always required for verification. And we aren't even going into "streaming" yet.

 

[Kat Tsun]

I fully expect that Boeing's design looks like a cross between the X-36 and Bird of Prey, scaled up to twin engines.

And that LockMart's design looked like the FB-22/X-44.

Ye given McDD and Boeing's history, it has the potential to be either the prettiest or the ugliest plane ever made, there is nothing in between.

 

[Seragina]

For VCE, a 3rd channel air flow should increase diameter. If outer channel dia. is restricted, so is inner channels, means impact on thrust.

Nah, more channel doesn't increase inlet size because the core (combustion chamber) is always much smaller. After all the air is compressed before being burned.

For flight at differnt speeds & altitudes, the area of intake, engine inlet & exhaust are related mathematically, IDK exactly how. Those propulsive efficiency formulas & equations are too much for me to handle.

That's why you should normalize it to sea level. For the F22 I think it was around 250 kg.
The problem here is we don't know if VCE and thrust increase given is normalized or not. This isn't your ordinary engine. The papers seems to give only a 10% increase for this technology. So the other missing 10% might indicate a need to increase air flow, hence, intake area.

How can a 6gen jet have :
- more weapons
- more fuel
- more range
- more speed
BUT engines smaller than previous ones?

If you reduce CS by 4-5%, then volume has to be compensated by increasing length, impacting area required for intakes, inlets, as i showed in diagram few pages back.

Look at my posted schematics. Counting pixels the CS was reduced to about 91.4% right after the intake section.
The saved space is due to the intake ducts no longer present or rather only 33% left for my design idea ofhaving it split up.

The removed fuel volume is compensated by incresing wing area which is required due to increased weight (payload+more fuel: a vicious cycle) and body length (longer IWB).

What I've not mentioned yet are the options for reducing intake duct volume.
Aside from DSI there are three more:
1. A slit design. It's the simpless of all but it seems to require an increase in "incoming" length at the lip. So not ideal for a small craft. I like it best due to simplicity eventhough I'm not certain about all the parameters that make it work yet.
2. A skrew duct. It reduces length dramatically due to the nature of round surfaces being large. Frankly, for the same reason it's undesireably wide and wiggling around. And imho the unused space is wasted and unuseable.
3. A similar design to above but applied to an ordinary duct. My bet is on this design.

I'll post a revised sketch sometime later for an evolved redesign but still losely based on the rendered design/source from the video.

 

[Sferrin]

And that's when we get this

Please. I'm eating lunch.

 

[Training_Dummy]

I thought the benefit of the third stream from adaptive engines was a) higher bypass for cruise efficiency b) power generation c) cooling and for less conventional things like fluidic thrust vectoring or novel control effectors. Given the rumors the first spiral of F-47 won’t have a three stream engine, we probably have to wait some time for the more fully realized version (hopefully not as long as Block 4 F-35!).

 

[bring_it_on]

Given the rumors

What are the sources of those rumors? Do they point to any specifics about what other configurations the first operational F-47's will have?

 

[Training_Dummy]

Point taken about the quality of the rumors and there has been a lot of noise with minimal powerplant info for F-47. That said, someone smarter than me pointed out GE and PW have not even built full XA102 and 103 demonstrators, to say nothing of testing and validation, implying F-47 IOC is a lot father out that the optimists believe or there is an interim powerplant (and what this means for the nozzle and other fluidic schemes like active flow control as integral effectors or not).

From what I have gleaned, and indicated in the post, such reports are a headscratcher for me given how integral VCE are to a lot of the more advanced FATE/ICE/JAST type notional concepts that NGAD presumably draws from.

Also posts like this
Post in thread 'USAF/USN 6th Gen Fighters - F/A-XX, F-X, NGAD, PCA, ASFS News & Analysis'
https://www.secretprojects.co.uk/th...-ngad-pca-asfs-news-analysis.3536/post-599055 keep me guessing to be honest.

 

[Scott Kenny]

Ye given McDD and Boeing's history, it has the potential to be either the prettiest or the ugliest plane ever made, there is nothing in between.

I cannot find any faults in this logic.

I'm hoping X-36+BoP, because at least that's attractive to me.

 

[Kat Tsun]

And that's when we get this

This isn't even the ugliest speculation I've seen.

Put the intakes on the bottom like YF-23 and it'd actually look alright.

 

[flateric]

This is not 'speculation'

 

[bring_it_on]

implying F-47 IOC is a lot father out that the optimists believe

I don't think there are any dates or even a range of specifics shared about when the F-47 is expected to IOC (from a programmatic perspective). Early to mid 2030s is certainly possible. As has been mentioned by others here before, engine development is expected to be the long tent in the pole that might push this to the mid 2030s instead of early 30s or 2030 as was originally envisioned.

I have no idea whether NGAD would use an interim engine and whether that will be pursued through IOC and not just to advance the program through early testing. But, if someone is going to make that claim (and I know where those are coming from), then it better be backed up by some evidence..the way things work now days is that these fairly weak rumors get circulated and repeated and before we know are indistinguishable from actual known information on the program..

 

[Low IQ Techie]

Nah, more channel doesn't increase inlet size because the core (combustion chamber) is always much smaller. After all the air is compressed before being burned.

That's why you should normalize it to sea level. For the F22 I think it was around 250 kg.
The problem here is we don't know if VCE and thrust increase given is normalized or not. This isn't your ordinary engine. The papers seems to give only a 10% increase for this technology. So the other missing 10% might indicate a need to increase air flow, hence, intake area.

Be it any size engine, if we wan't a VCE in same engine volume, it can be made by dividing the same inlet dia. into 3 co-axial sections.
But it should SIGNIFICANTLY INCREASE dry/wet thrust & reduce SFC (Specific Fuel Consumption).
Just 10% more thust is not enough as per 6gen capability specs.

The latest Civil engines like GE9X, etc are proof of massive size increased due high BPR=10, OPR=60-61 resulting in high economy. Obviously fighter engines can't be made like that.
KE = 0.5 x M x V^2
If Air Mass Flow is 2x then KE is 2x, some more BPR.
but if Velocity is 2x the KE is 4x, but that needs more fuel burning.
So to make 4x KE w/o more fuel burning, 4xM is needed= 4x inlet area (more BPR) = 2x inlet dia.

Example, if F119's dry/wet thrust of 116/156 KN needs to be increased by 50% to 174/234 KN primarily by Air Mass Flow, then inlet area may need increase by 50% or diameter by square-root(1.5)=1.2247 or 22.47% >> 122cm.

Look at my posted schematics. Counting pixels the CS was reduced to about 91.4% right after the intake section.
The saved space is due to the intake ducts no longer present or rather only 33% left for my design idea ofhaving it split up.

The removed fuel volume is compensated by incresing wing area which is required due to increased weight (payload+more fuel: a vicious cycle) and body length (longer IWB).

What I've not mentioned yet are the options for reducing intake duct volume.
Aside from DSI there are three more:
1. A slit design. It's the simpless of all but it seems to require an increase in "incoming" length at the lip. So not ideal for a small craft. I like it best due to simplicity eventhough I'm not certain about all the parameters that make it work yet.
2. A skrew duct. It reduces length dramatically due to the nature of round surfaces being large. Frankly, for the same reason it's undesireably wide and wiggling around. And imho the unused space is wasted and unuseable.
3. A similar design to above but applied to an ordinary duct. My bet is on this design.

I'll post a revised sketch sometime later for an evolved redesign but still losely based on the rendered design/source from the video.

AFAIK,
> For rotary turbo engines, the inlet air speed has to be subsonic even at aircraft's supersonic speeds.
> The Afterburner shock-diamonds means supersonic exhaust, but still the inlet air has to be subsonic, which is done in 4gen jets by moving inlet lips, ramps & in 5gen jets by convergent-divergent ducts.
> The shape/angle of inlet give idea about aircraft's supercruise/max speeds, as they interact with sonic shock waves.
> When it comes to Air Mass Flow the smallest CS perpendicular to air flow is taken, not area of angled wedge inlet lip or outermost edges. So imagine a wedge intake like F-14/15/Su-3X with frontal CS as 1x1=1sqm, angled wedge edge area as 3 sqm, then 1x1 sqm matters.

Compared to original F-22 for example, a SLIT like narrow intake might look like following:
IDK if any X/Y jet with such intake.



What do mean by SKEW duct?

 

[Training_Dummy]

I don't think there are any dates or even a range of specifics shared about when the F-47 is expected to IOC (from a programmatic perspective). Early to mid 2030s is certainly possible. As has been mentioned by others here before, engine development is expected to be the long tent in the pole that might push this to the mid 2030s instead of early 30s or 2030 as was originally envisioned.

I have no idea whether NGAD would use an interim engine and whether that will be pursued through IOC and not just to advance the program through early testing. But, if someone is going to make that claim (and I know where those are coming from), then it better be backed up by some evidence..the way things work now days is that these fairly weak rumors get circulated and repeated and before we know are indistinguishable from actual known information

Sir, this is an Internet forum.

 

[bring_it_on]

Sir, this is an Internet forum.

I get that. Let's get back to this when we actually come across some hard evidence as to what powerplant the F-47 is likely to have when it enters service (and when that milestone is required to be achieved).

 

[dark sidius]

This style is interesting

 

[FlyGuy369]

I get that. Let's get back to this when we actually come across some hard evidence as to what powerplant the F-47 is likely to have when it enters service (and when that milestone is required to be achieved).

Best evidence I have on any king of three stream engine tech are these. PW & GE. None of them say "F-47" but for the sake of "possible configuration", these are good crumbs.

 

[dark sidius]

Best evidence I have on any king of three stream engine tech are these. PW & GE. None of them say "F-47" but for the sake of "possible configuration", these are good crumbs.

USAF want to keep the design secret surely until the roll out.

 

[dark sidius]

Rodrigo Avella speak about round inlet , it seem this one model have it.

 

[Jackonicko]

I assume that may have been Lockheeds approach, probably which was also favored by Kendall. The tailless deltafied F-22 we all have come to associate with NGAD over the years, the shape Lockheed Martin teased in all sorts of artwork and videos. Clearly evolutionary.

Now Boeing however, as far as the rumors go, which are also somewhere in the NGAD thread, presented a more revolutionary rather than evolutionary design. And while Lockheeds designs from the F-22 to the F-35 were very iterative (I'd also argue the F-117 already introduced some of the design characteristics, but maybe I'm reaching here), when we look at Boeing/MDDs X-36, Bird of Prey and X-32...well we see that Boeing is very daring, very sci-fi, very revolutionary in how they approached low observable aviation so far.

So I can definitely see dihedral, canards, even the gullwings based on that. I don't think it will be a J-36 style tailless delta arrowhead type design, I think that was probably Lockheeds losing bid.

This is all speculation. There's no evidence that Kendall was referring to Lockheed's design, nor that he 'favoured' it. We know that Kendall was familiar with both designs. We can infer that he knew that Boeing was the preferred choice when the programme was paused, and that he was referring to the winning NGAD design, or perhaps to both, but almost certainly NOT to the losing LM design.

And we know that senior officials have effectively discounted the Oval Office reveal CGIs, and that Kendal described the F-47 as having an “aircraft configuration itself [that] is going to be [a] pretty direct descendant of F-22.”

That may be inconvenient for those who have produced artwork of more exotic designs with canards and dihedral, or to those who have their own pet theories, but I'd say that a direct quote from the SECAF who presided over NGAD until the pause should carry a fair bit more weight than speculation based on CGIs which we know to have been deliberately misleading, especially when they lead us to conclusions that are more stable and less stealthy that we'd expect.

 

[EmoBirb]

That may be inconvenient for those who have produced artwork of more exotic designs with canards and dihedral, or to those who have their own pet theories, but I'd say that a direct quote from the SECAF who presided over NGAD until the pause should carry a fair bit more weight than speculation based on CGIs which we know to have been deliberately misleading, especially when they lead us to conclusions that are more stable and less stealthy that we'd expect.

I think most of us (people that speculate) look less towards the renders, which are very bare. More so we look at previous Boeing VLO efforts like the Bird of Prey, X-32 or X-36. And it may be coincidence that the very bare bones renders presented reflect some aspects of these, but maybe it's not.

A "clear descendant of the F-22" can mean many things, it could only refer to its role and performance goals. But maybe it's layout, maybe not. I personally doubt that Boeing would somehow come up with an iterative evolution of a 30 year old aircraft developed by their bitter rival in the industry. As for Kendall, I have many things to say about him and what anything he said is worth. But that's not for this forum whatsoever so I keep it to myself.

 

[Scott Kenny]

I get that. Let's get back to this when we actually come across some hard evidence as to what powerplant the F-47 is likely to have when it enters service (and when that milestone is required to be achieved).

While the USN has explicitly rejected 3-stream engines in FAXX (at least for first production run), USAF seems to be holding strong for the Adaptive engines in the F-47.

This is all speculation. There's no evidence that Kendall was referring to Lockheed's design, nor that he 'favoured' it. We know that Kendall was familiar with both designs. We can infer that he knew that Boeing was the preferred choice when the programme was paused, and that he was referring to the winning NGAD design, or perhaps to both, but almost certainly NOT to the losing LM design.

And we know that senior officials have effectively discounted the Oval Office reveal CGIs, and that Kendal described the F-47 as having an “aircraft configuration itself [that] is going to be [a] pretty direct descendant of F-22.”

That may be inconvenient for those who have produced artwork of more exotic designs with canards and dihedral, or to those who have their own pet theories, but I'd say that a direct quote from the SECAF who presided over NGAD until the pause should carry a fair bit more weight than speculation based on CGIs which we know to have been deliberately misleading, especially when they lead us to conclusions that are more stable and less stealthy that we'd expect.

1) remember that there was an F-15 version with Canards, the STOL/Maneuverability Test Bed, and IIRC it was seriously proposed as the replacement for C/D models.

2) "configuration" can cover a lot of ground. I'm taking it to mean "twin engine, 6+2 AAM capacity, and highly maneuverable"

 

[djfawcett]

While the USN has explicitly rejected 3-stream engines in FAXX (at least for first production run), USAF seems to be holding strong for the Adaptive engines in the F-47.




1) remember that there was an F-15 version with Canards, the STOL/Maneuverability Test Bed, and IIRC it was seriously proposed as the replacement for C/D models.

2) "configuration" can cover a lot of ground. I'm taking it to mean "twin engine, 6+2 AAM capacity, and highly maneuverable"

I am taking "configuration" as some derivative or iteration of the X-44. From a certain individual who is a liaison between a certain company and congress, Kendall had a preference for the Lockheed low risk approach. One can possibly understand now why Kendal punted. Nothing like Trump telling him post employment - - to "kiss my big backside."

 

[Scott Kenny]

I am taking "configuration" as some derivative or iteration of the X-44. From a certain individual who is a liaison between a certain company and congress, Kendall had a preference for the Lockheed low risk approach.

Which is certainly what I expected the LockMart NGAD proposal to look like anyways.

And if you're trying for a quicker development cycle, low risk is better. Especially if you're doing high risk things in other places in the development, like government-owned designs and MOSA.

One can possibly understand now why Kendal punted. Nothing like Trump telling him post employment - - to "kiss my big backside."

Yep!

 

[joshjosh]

And we know that senior officials have effectively discounted the Oval Office reveal CGIs, and that Kendal described the F-47 as having an “aircraft configuration itself [that] is going to be [a] pretty direct descendant of F-22.”

That may be inconvenient for those who have produced artwork of more exotic designs with canards and dihedral, or to those who have their own pet theories, but I'd say that a direct quote from the SECAF who presided over NGAD until the pause should carry a fair bit more weight than speculation based on CGIs which we know to have been deliberately misleading, especially when they lead us to conclusions that are more stable and less stealthy that we'd expect.

Here's what Frank Kendall said on the Defense & Aerospace podcast on March 26th:

Question:
I've got a couple of questions to ask, but I want to start and pull in Andrew what you said and Frank what you said and draw off of something that John Jumper told us a couple of weeks ago. He said, when people think about this plane, it is not an F22 replacement and don't think about it as an F22 replacement. Think about it as a penetrating quarterback to control battle space forward even if the airplane has potent other capabilities, right? Frank, how would you best define or describe the airplane for folks who are looking at this as kind of the Super Fighter and the next generation F-22 when it seems like what all three of you are saying is "don't think of it as a one for one F22 replacement," It is kind of a different platform. And if So, what makes it different?
Frank Kendall:
I would think of it as both, OK? Although the quarterback roll came during my tenure as Secretary of the Air Force with the introduction of the idea of uncrewed collaborative combat aircraft. The original requirements were essentially for an F-22 replacement, and that's essentially the design we have. But the aircraft, like the F-35, like 4th generation aircraft like the F15 or the F16, will be capable of controlling uncrewed collaborative combat aircraft, "loyal wingmen," and operating the way that John Jumper suggested. So while the aircraft configuration itself is going to be pretty direct descendant of F-22, more recently that role's been expanded so that it can do other things, particularly control CCAs as well.
Andrew Hunter:
I would add to that that the conception of the architecture for the program—and I know architecture is a word that can sometimes make people go to sleep, but bear with me for a second—you know, the architecture for the program, the Advanced Mission Systems Government Reference architecture is that not only the sensors on NGAD platforms can talk to each other, similar in many respects the way that F-35 can talk to each other, but that same architecture supports sensors on other platforms. And so it's kind of starting with a network first approach, vice of a, you know, alone and unafraid fighter kind of an approach.

I think it's pretty clear that Kendall and Hunter were saying that the F-47 would be a large, heavy, stealthy, very capable, penetrating air superiority platform, like the F-22. They were responding to the question about whether the F-47 wouldn't really be a "fighter" but more of a drone quarterback with capabilities disaggregated to the drones it controls. Kendall and Hunter were saying that it would be both a very capable platform by itself, but also able to natively control CCAs for additional effect.

They were not saying it would have a planform similar to the F-22. An aircraft with an exotic planform, canards, or whatever else you can think of could still fit the description given by Kendall and Hunter.

 

[Scott Kenny]

I think it's pretty clear that Kendall and Hunter were saying that the F-47 would be a large, heavy, stealthy, very capable, penetrating air superiority platform, like the F-22.

At least in my mind, the F-22 isn't a "heavy fighter". I mean, if we're saying the F-15 is a heavy fighter because it's a twin engine and carries 4+4 AAMs then yes it's a heavy fighter, but my mind goes to "F-111" when I hear "heavy fighter".

 

[joshjosh]

At least in my mind, the F-22 isn't a "heavy fighter". I mean, if we're saying the F-15 is a heavy fighter because it's a twin engine and carries 4+4 AAMs then yes it's a heavy fighter, but my mind goes to "F-111" when I hear "heavy fighter".

"Heavy" is my editorialized characterization of the F-22. We could just say this instead:

I think it's pretty clear that Kendall and Hunter were saying that the F-47 would be a very capable penetrating air superiority platform, like the F-22.

 

[EmoBirb]

At least in my mind, the F-22 isn't a "heavy fighter". I mean, if we're saying the F-15 is a heavy fighter because it's a twin engine and carries 4+4 AAMs then yes it's a heavy fighter, but my mind goes to "F-111" when I hear "heavy fighter".

I'd argue the F-22 is a heavy fighter. Large, heavy, top of the line, twin engine fighter. Same with the Su-57 and J-20 (or the F-15, Su-27 and J-11 before them).

The F-111 was a fighter bomber I'd argue, like the Su-24, Su-34 or Tornado.

 

[Scott Kenny]

I'd argue the F-22 is a heavy fighter. Large, heavy, top of the line, twin engine fighter. Same with the Su-57 and J-20 (or the F-15, Su-27 and J-11 before them).

The F-111 was a fighter bomber I'd argue, like the Su-24, Su-34 or Tornado.

Right, but there's "twin-engined fighter" like Legacy Bug (23klbs empty), Rafale (23.4klbs empty for the -M), or Typhoon (24,250lbs empty); and then there's F14s (43,750lbs empty/74,300lbs MTOW), F-111Bs (46,100lbs empty/88,000lbs MTOW) or MiG-31s (48,100lbs empty/102,000lbs MTOW) today. I'm going to ignore the "tiny twins" like F-5s, F-CK-1s, and M346s, those are glorified trainers at best.

For that matter, an F-15C has an empty weight of 29,000lbs while a Tomcat has a 43,750lb empty weight. F-111B was talking about an Empty Weight of 46,100lbs. Super Bugs are 32klbs empty. The F-18L would have weighed in about 20klbs empty. MiG-29 is ~24,250lbs empty.

Now. F-22 is 43klbs empty, J-20 is ~37.5klbs empty, Su-57 is ~40.8klbs empty, FC-31/J-35 is ~38.6klbs empty, KF-21 is 26klbs empty and is an extreme outlier on the small end that I'm not comparing in this paragraph. So yes, the F-22 is the heaviest of the existing "fifth generation fighters" but only by about 5500lbs empty weight. At MTOW? Well, F-22 is 83.5klbs, J-20 is 81.6klbs, and Su-57 is 77.2klbs (I don't have an MTOW for the J-35). So the F-22 is still the heaviest MTOW, but only by 6300lbs when compared to the lowest MTOW in the group. It's really close to the same as the J-20, a 1900lb difference. So all the major twin engine "Fifth Generation Fighters" are pretty close to the same weight, both Empty and MTOW.

Expected weight increase from 4th Gen to 5th Gen.

• F-16C-50/52 is about 18.9klbs empty and F-35 is 29.3klbs empty, a ~55% increase in empty weight. However, the F-16 only carries 7000lbs of fuel internally, while the F-35 carries 18,000lbs of fuel, roughly 2.5x more fuel.
• F15C versus F-22 is 29k versus 43k, a ~48% increase, but the F-22 also carries about 4500lbs/33% more fuel (18klbs versus 13.5klbs).
• Su-27 is about 36.1klbs empty, while the Su-57 is 40.8klbs and the J-20 is 37.5klbs empty (I'm assuming that the J-20 is more closely related to the Flanker than the Fulcrum). That's a 13% weight increase for the Su57 and a 3.8% increase for the J-20. I suspect that a big part of that is the relatively small increase in internal fuel that the planes have. A Flanker has 20.7klbs internal fuel, while the Su-57 has 22.7klbs internal fuel, and the J-20 has 26klbs internal fuel.
• The interesting size comparison is the KF21 versus Hornet, Legacy and Super. KF21 is only 26klbs empty while an F-18L was about 20klbs empty and a Super Hornet is 32klbs empty. That's a 30% weight increase compared to the Legacy Bug and an 18.875% reduction compared to a Super Bug, a very small increase in weight for a design that supposedly includes volume for an internal bay already plus ~2500lbs/22% more internal fuel.

So, I'm saying that I expect a Fifth Generation "front line fighter" like the F-22, Su-57, or J-20 to weigh about 25%-50% more than their previous generation that they're replacing, depending on just how much more internal fuel you're adding.

I think for Jets I'm calling a Heavy Fighter in the 4th-5th-6th generations "something with over a 100,000lb MTOW," like the MiG-31 and almost guaranteed like the J-36. And like the F-111A/C/D/E/F/G and FB-111. Tomcat and F-111B Sea Pig are big powerful fighters, but don't make the MTOW cut. Definitely using 100k MTOW for 5th and 6th generation aircraft as "heavy fighter", we can argue how low the MTOW cutoff should go for 4th Generation.


==========================

Or, for prop-plane comparisons, the P-38 (12.8klbs empty/21.6klbs MTOW) versus F7F Tigercat (16.3klbs empty/25.7klbs MTOW) versus P-61 (23.5klbs empty/36.2klbs MTOW). Not an entirely fair comparison, as the P-38 was designed in the late 1930s (first flight in 1939) while the Tigercat was designed during the war (first flight in 1943) as was the P-61 (first flight in 1942). So the P-38 is relatively undergunned as a heavy fighter or zerstorer with 4x .50cal and only 1x 20mm. A radar-free Tigercat and a P-61 have the same armament: 4x .50cal and 4x 20mm (radar replaces the .50cals in the Tigercat). They even have the same engines, a pair of R2800s, though the P-61 makes 150 more horsepower per engine and has 4-bladed props instead of 3-bladed props. A P-38 makes 1600hp per engine, while the F7F makes 2100hp per and the P-61 makes 2250hp per engine. The 1000 extra horsepower with only ~4000lbs extra weight makes the F7F massively outperform the P-38.

But the P-61 empty weighs more than a P-38 does at MTOW! The P-61 weighs 44% more than an F7F empty, 41% more at MTOW. Now, that's a Heavy Fighter!

 

[F-14ATomcat]

A model of what i think F-47 might look like

 

[Scott Kenny]

A model of what i think F-47 might look like



View attachment 769876


View attachment 769878
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View attachment 769890

I think I agree with the "engines above the wing spar" design you've got here. That would allow for the inlet trunks to go up and over the top of the weapons bay, and allow for a 12ft or even 15ft side bay for AMRAAM/JATM or SiAW.

 

[F-14ATomcat]

I think I agree with the "engines above the wing spar" design you've got here. That would allow for the inlet trunks to go up and over the top of the weapons bay, and allow for a 12ft or even 15ft side bay for AMRAAM/JATM or SiAW.

I think use the engine nacelle to hinge a flap and the nozzle with a hinged part working as a vertical rudder would allow a cleaner wing, basically I think the YF-23 is the best concept for a 6th generation fighter

 

[Hydroman]

A model of what i think F-47 might look like



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I'm impressed with the new, low-cost, high strength paper composite material.

 

[Jackonicko]

The word configuration has a pretty specific meaning. And he said:

"The aircraft configuration itself is going to be pretty direct descendant of F-22..."

He didn't say concept, he didn't say role, he said configuration. And then used the word descendant.

He didn't say: "that the F-47 would be a very capable penetrating air superiority platform, like the F-22."

He didn't say: "twin engine, 6+2 AAM capacity, and highly maneuverable"

You might: "personally doubt that Boeing would somehow come up with an iterative evolution of a 30 year old aircraft developed by their bitter rival in the industry."

Arguably that's exactly what they did with MQ-28, and some of the Boeing CGIs are not a million miles from the F-22's configuration.

And other official sources have basically rubbished the official F-47 artist's impressions, making them an unreliable basis for what the actual aircraft will look like - especially when it comes to wing dihedral and canards, I'd maintain.

 

[quellish]

I think it's pretty clear that Kendall and Hunter were saying that the F-47 would be a large, heavy, stealthy, very capable, penetrating air superiority platform, like the F-22.

Where did they say it would be large or heavy?

 

[joshjosh]

The word configuration has a pretty specific meaning. And he said:

"The aircraft configuration itself is going to be pretty direct descendant of F-22..."

He didn't say concept, he didn't say role, he said configuration. And then used the word descendant.

Configuration does not mean planform. He was responding to a question about whether the F-47 would even resemble a traditional fighter, what with its large radar, maneuverability, AAMs, active self protection, and other features we typically associate with fighter jets today. His response was that yes, it would it some way resemble the fighter jets we know today, rather than just being a "drone controller." Kendall was not saying that the planform of the F-47 would resemble that of the F-22, and to claim as much is a stronger claim than what I have made; and not, I believe, a claim with textual evidence from this particular Kendall conversation.

 

[red admiral]

Configuration does not mean planform

In aircraft design, then configuration definitely means gross external shape (planform included in this) as well as internal layout of major items like engines, payload bays, ducts, landing gear etc.

But we have no idea whether Sec. Kendall was using the word in this sense

When talked about as configuration as descendent from F-22 then the likes of Cummings' NGAD concept for AvWeek fits in this. Major internal layout is like F-22. Wings/Empennage are different.