Lockheed Martin F-22A Raptor

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I hope it goes well, the concept IS the ideal. What happens in the real world is the test.
 

BDF

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About the only thing the F-22 has over an F-35 is kinematic performance. An F-35 is superior in most any other measurable way. I think a much better short term option would be to stretch out and re-engine the F-35 to optimize it as an interceptor. That would be far easier to do than redesigning the F-22 and re-establishing a product line. The F-35A suffers from poor aerodynamics driven by the length limitations of the USMC; if you stretched the fuselage out you could achieve much better top speed and acceleration even with the current engine. It already is a borderline supercruise design.

But I still think focusing on NGAD is the best option of all.
Kinematics are very important though. The Raptors speed/altitude advantage and the ability maneuver in those regimes is a significant advantage. Had the opportunity to have lunch with a F-15 IP when I was in Portland a few weeks ago. He's also qualified as a A-A mission commander and has participated in several LFEs with both the F-22 and '35. I asked about the viability of the F-35 as being the primary air superiority machine since I've heard this idea quite often. His perspective is that its a great all around jet but he felt that the mission set still requires a machine that specializes in that capability. He was obviously limited in what he could discuss but was adamant that there are capabilities the F-22 has that the F-35 cannot match that are important to the high end A-A fight. He was a funny guy and his final comment on the subject was "it's a great jet but there's a reason why we call it fat Amy!" It was a interesting convo to say the least!

Anyway to make the changes you suggest would be expensive, take time and probably only marginally better if better at all than the F-22 and almost certainly inferior to the NGAD concepts. I'm all for buying a ton of F-35s, especially now, but keep the Raptor going until the NGAD replaces it.
 

Acatomic

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@BDF

There was an article I read a couple years ago with a retired US airforce general or something, that said the same thing: one F-35 couldn't replace one F-22 due to kinematics, but, he went on to say, you could leverage F-35's sensor fusion and network centric capabilities to make up for poor kinematics. In that case you would need 8 F-35's to replace 2 F-22's and that's why it's important for the air force to get all of the planned F-35's (1763).

I'll try to find the article and post it here.
 

Josh_TN

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The F-35 does bring a lot to the table in terms of ISR, even for air to air. But yeah, cruising at 50k feet at Mach 1.7 without reheat is pretty unparalleled in terms of engaging a target. I'm not trying minimize that, I'm just saying that refurbishing an F-22 is such an involved process you might as well build a new aircraft anyway. I'm sure they will see continued use until at least NGAD delivering a product, whenever that occurs. Hopefully that program isn't too ambitious; the B-21 program seems to be settling for modest goals and established technology and reaping the rewards in terms of program cost and time frame.
 

gtg947h

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That a redesign of a known plane and known production line costs as much as the development of new technology and solutions that need to be tested and validated from zero cannot be sustained in view of how development and industrialization of complex systems work. Development starts from virtually "zero certainty" and progresses slowly through iterative processes into ever higher levels of knowledge of the system parts and their interaction in ever more complex modes and scenarios. When a plane has been tested for more than 10 years and operated for 15 like the F-22, everything is pretty much known and modifications can be made where just a small proportion of the relevant elements change and most of their interactions are known.
The problem is that a lot of the F-22 data is not known, by this point. Suppliers are out of business. Institutional knowledge is gone. Tooling (which is important, but not the be-all end-all of producing aircraft) is of uncertain status. Many systems components just can't be found any more--the equipment that produced them is gone. Some materials--alloys, adhesives, composite fabrics, and more--may not be available any more. Many of the drawings probably exist only on paper/mylar, or in obsolete CAD files that can't be read directly any more.

There's a heck of a lot more to it than "just dust off the blueprints and make more parts". You really would have to reverse-engineer quite a bit. You'd have to find new suppliers and qualify brand-new systems even if they just do the same things the old ones did. You'll need to requalify your processes, especially things like composite curing, chemical and heat treatment, etc. You need to generate all-new manufacturing orders and production setups; the old stuff (if you can even find it) is written for the old production line that's gone now.

At that point you're at a significant fraction of the time and money it takes to make something brand new. Would you spend $20,000 repairing a 15 year old car, if you could buy a new one for $25,000?
 

BDF

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@BDF

There was an article I read a couple years ago with a retired US airforce general or something, that said the same thing: one F-35 couldn't replace one F-22 due to kinematics, but, he went on to say, you could leverage F-35's sensor fusion and network centric capabilities to make up for poor kinematics. In that case you would need 8 F-35's to replace 2 F-22's and that's why it's important for the air force to get all of the planned F-35's (1763).

I'll try to find the article and post it here.
It was in referencing to attacking a SAM site. It wasn't in reference to the A-A domain.
 

LMFS

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The skin coatings can and AFAIK have been applied in some sense, but one of the key maintenance drivers with previous stealth aircraft's skins embedded into the composite with the F-35, so to get the same resilience against delamination you'd need to replace all the composite panels on the F-22, and that could possibly involve redesigning some access panels, sensor apertures, etc if the F-35's composites are thicker than the F-22's or vice versa.
Then redesign those panels and apertures, where is the problem?
Ultimately, if NGAD doesn't go terribly wrong, what will be the point in keeping the F-22 fleet?
If you don't upgrade the F-22 now, you will not have B plan in case NGAD goes wrong. And besides, what you learn for the F-22 can be of great use for the NGAD. This is again the basics of risk management, not that anybody in command seems to care.
At that point you're at a significant fraction of the time and money it takes to make something brand new. Would you spend $20,000 repairing a 15 year old car, if you could buy a new one for $25,000?
Because of that logic some people with dubious interests neglect the most basic support measures for planes in operation, so that in the future it is easier to discourage modernization programs from threatening juicy funding for high risk, alternative free ones. The same MO that lead to the current failed programs, applied all over again for the same reasons and with the same apparent "popular" support is something difficult to understand.
 

Josh_TN

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The skin coatings can and AFAIK have been applied in some sense, but one of the key maintenance drivers with previous stealth aircraft's skins embedded into the composite with the F-35, so to get the same resilience against delamination you'd need to replace all the composite panels on the F-22, and that could possibly involve redesigning some access panels, sensor apertures, etc if the F-35's composites are thicker than the F-22's or vice versa.
Then redesign those panels and apertures, where is the problem?
Ultimately, if NGAD doesn't go terribly wrong, what will be the point in keeping the F-22 fleet?
If you don't upgrade the F-22 now, you will not have B plan in case NGAD goes wrong. And besides, what you learn for the F-22 can be of great use for the NGAD. This is again the basics of risk management, not that anybody in command seems to care.
At that point you're at a significant fraction of the time and money it takes to make something brand new. Would you spend $20,000 repairing a 15 year old car, if you could buy a new one for $25,000?
Because of that logic some people with dubious interests neglect the most basic support measures for planes in operation, so that in the future it is easier to discourage modernization programs from threatening juicy funding for high risk, alternative free ones. The same MO that lead to the current failed programs, applied all over again for the same reasons and with the same apparent "popular" support is something difficult to understand.

Why do you think rebuilding the F-22 production line would have less risk than NGAD? It’s a locked in vendor that holds the source code and would have all of the same risks as building a new aircraft, with basically no benefit. You seem to think that an F-22 rebuild would be devoid of risk despite the fact that it would be a brand new production line like a new aircraft.
 

gtg947h

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The skin coatings can and AFAIK have been applied in some sense, but one of the key maintenance drivers with previous stealth aircraft's skins embedded into the composite with the F-35, so to get the same resilience against delamination you'd need to replace all the composite panels on the F-22, and that could possibly involve redesigning some access panels, sensor apertures, etc if the F-35's composites are thicker than the F-22's or vice versa.
Then redesign those panels and apertures, where is the problem?

Where is the problem? The problem is that "just" redesigning the F-22 to use the F-35 skin materials means basically a complete redesign of the structure. You can't "just" substitute a different material with different physical properties. Best case, the material is basically equal in strength and stiffness to the old stuff and you see no thickness change. Then, you get to redo all of your loads analysis and your fatigue testing and your loads flight testing, recertify the LO properties, develop a new database of acceptable repairs, and stand up new manufacturing instructions specific to F-22 parts.

If you get any thickness change, now you're either altering the outer mold line of the aircraft (which means redoing your aero testing, your LO testing, and more), and/or you're having to redo all the internal structure to shrink it a bit and maintain that OML. And then you get to do all that testing and analysis work mentioned in the best case scenario.

If there's any significant differences in material properties, you get to have even more fun and pretty quickly you're going down the road of making a brand-new airplane design that just happens to look like an F-22 on the outside. And you still have to test it.


Few people not involved in things like this really understand what goes on to actually making them happen. Most people seem to think all the money goes into design... but a substantial part of the development funds go into testing and proving that your design does what you say it does and that you can build it repeatably, and doing all of the associated paperwork and tracking of your processes.
 

LMFS

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Why do you think rebuilding the F-22 production line would have less risk than NGAD? It’s a locked in vendor that holds the source code and would have all of the same risks as building a new aircraft, with basically no benefit. You seem to think that an F-22 rebuild would be devoid of risk despite the fact that it would be a brand new production line like a new aircraft.
It is obvious that it would have way less risks, because it has already been done. As to the vendor thing, defence is not market economy since there is only one buyer and the issues are of existential relevance for the state. USAF establishing the prices of the F-35 lots for Lockheed should have made it clear for the ones still in doubt. Once US government gets serious about the issue (think of a war), Lockheed and the rest of involved vendors would get those lines operating again in a matter of months. I should not need to argue that US government has full authority on US based companies, even more on those working in strategic branches.
Where is the problem? The problem is that "just" redesigning the F-22 to use the F-35 skin materials means basically a complete redesign of the structure. You can't "just" substitute a different material with different physical properties. Best case, the material is basically equal in strength and stiffness to the old stuff and you see no thickness change. Then, you get to redo all of your loads analysis and your fatigue testing and your loads flight testing, recertify the LO properties, develop a new database of acceptable repairs, and stand up new manufacturing instructions specific to F-22 parts.

If you get any thickness change, now you're either altering the outer mold line of the aircraft (which means redoing your aero testing, your LO testing, and more), and/or you're having to redo all the internal structure to shrink it a bit and maintain that OML. And then you get to do all that testing and analysis work mentioned in the best case scenario.

If there's any significant differences in material properties, you get to have even more fun and pretty quickly you're going down the road of making a brand-new airplane design that just happens to look like an F-22 on the outside. And you still have to test it.
You don't know what the difference in properties and thickness of those panels is, and the improvement in technology in the time passed most probaly allows to fine tune the materials as required or even get better properties than the original ones. The tasks you mention are logical and still a fraction of the problems you will find with a completely new plane with new technologies. Somehow with NGAD everything will be 100% rosy despite that never been the case with such programs, but with a simple modernization of the F-22 everything will be as bad as it could and then some more, that is not technically serious. You say a change of some mm in the size of the plane demands to do the whole design again, right? How do CFTS get applied to planes then, instead of designing new platforms?
Few people not involved in things like this really understand what goes on to actually making them happen. Most people seem to think all the money goes into design... but a substantial part of the development funds go into testing and proving that your design does what you say it does and that you can build it repeatably, and doing all of the associated paperwork and tracking of your processes.t
That is precisely the issue, that I do have experience in development and program management, and many of these "worst practices" and "risk augmentation" measures used by US MIC would be considered outright negligence in any serious industry. A clean slate design has orders of magnitude more uncertainty that a modification of an existing design. That is a fact, sorry about it.
 

Firefinder

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That is precisely the issue, that I do have experience in development and program management, and many of these "worst practices" and "risk augmentation" measures used by US MIC would be considered outright negligence in any serious industry. A clean slate design has orders of magnitude more uncertainty that a modification of an existing design. That is a fact, sorry about it.
Good then here is a thought exercise.

Imagine coming back to a program you finish ten plus years ago. Its been dead that entire time with no one making sure it stays properly update with the current stuff. And you lost the notes three computers ago, and all the other support gear is long gone. And dont thinking about asking your former coworkers, they are either dead, blacklisted, to busy or trash their own notes long ago.

Exactly how easy will it be for you to get back in the saddle and get this barely a zombie of a program alive again?

It be a PITA that drive you to drink wouldn't it?

Now take that but you are on a different program that YOU HAVE NO CLUE ABOUT with only the handful of notes cause they are black out by some hyperactive squirrel with a marker years ago if not out right lost in the mess that is the archive. Oh and a bunch of critical materials are no longer even made being replace with something different years ago so now you have to mod the design around that before doing you own mods. But first you have to figure out how the design actually works, the stresses and the like, cause the last guy to know was killed two years ago. And the only other living one is blacklisted for selling secrets.

Basically you are told that you have make the FA22 Raptor a thing with only what you already know about it.

Starting fresh starting to look far better isn't it?

Cause the second one is how making the FA-22 Super Raptor will be like.
 

TomcatViP

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Everything is doable in that domain as much as you have time and knowledge.

The paradox here is to have to invest significant amounts of money for something that would be outclassed in the next 20 years.
It won't bother much the USAF if that was about the a-10 but their Raptor is a key component in air dominance and that is paramount in the US strategic thinking.

Last but not least, those Raptors are probably not lost and could fill key allies defence needs in a synergistic improvement of our overall defense.
 

Firefinder

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Last but not least, those Raptors are probably not lost and could fill key allies defence needs in a synergistic improvement of our overall defense.
Sad thing is that the Raptor is far more likely to get a F14 Tomcat type of send off. Straight to the shredders, cause the thing is still one of the more advance planes out there and I cant see Congress going back on the NOT FOR SALE discussing they made over a decade ago.

Also have some more information on the whole retirement plan and the issues the Air Force has with the Raptor

Seems like the plan is to hopefully have the NGAD up and running by the end of the decade but there are plans to keep the Raptor running up to 2040 if needed. WIth the Raptor retirement in lockstepped on the NGAD planes development.

Also I am surprise A2A mag depth was consider an issue, A2G I can understand cause the F22 was design as a fighter first, but A2A? Must be the new A2A missiles getting bigger then expected or something...
 

LMFS

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Good then here is a thought exercise.
The way you put it the plane could not be even operated by now, but the fleet has been going repairs, low level structural modernizations, SW and coatings upgrades already, that I remember, so I don't think the situation is as catastrophic as you describe it. The Raptor was commissioned little ago, designed at a time where computers were already used and if the case is that all documentation was lost the way you describe it, then I would be rather seeing it as a problem of high treason more than a development issue. BTW something along those lines was needed to restore the production of the Tu-160, which was actually done with documentation on paper so long ago that most people were physically not among us any more. It was a big effort, but the platform was worth it. In a second post you rightly describe the F-22 as one of the most advanced planes to the point that US may still not clear it for export. I can tell you the money of the sale of the planes which are considered "non viable" for US by the end of this decade would be more than enough to make the modernization program profitable again, since such high end platforms are an absolute premium for any state and countries like Japan, KSA and several others would pay a fortune for them. Foreign countries would get a sanitized version with modern detuned avionics and updated F119 engines, while USAF would get the full package with adaptive engines and any other top of the line systems that would be ongoing testing for the NGAD. And with such a plane in the fleet, the following benefits would be achieved for the NGAD program:
> No vendor can hijack the program, because the USAF can simply ditch them and use their up to date, 100% fleet compatible F-22, at an acceptable cost in terms of capability
> The program is hedged against unexpected change in the level and nature of threats and unexpected technical difficulties, and can be extended in the future without seriously compromising the defence of the country or demanding massive money injections like happened with F-35.
> The systems, technologies and doctrines intended for the NGAD can be tested in the intermediate step of the modernized F-22

This is how you go about risk mitigation on a complex, strategically critical, high risk program, if you are doing things the way they should be done and without questionable interests interfering.

Just wanted to touch upon the issue because I cannot technically agree on the narratives been spread to justify ditching the F-22. But ok, point made, so that's it from my side.
 

Jimmo952

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This retire the F22 thing is about the Airforce being willing to make hard choices to get what they want, which is NGAD.

Only time will tell if NGAD is worth it.
 

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Stumbled into this website and just passing it on... Can't get website link to work on my tablet- sorry

fullafterburner.weebly.com/aerospace/lockheed-f22-raptor-the-definition-of-stealth
 

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I have a what may be a rather silly naive question... Where is the gun camera located on the raptor? Is in on the nose beneath the canopy in what looks like it could be an optical sensor or is that part of the UV sensor sensor system? I don't see anything else anywhere else that looks like a camera.
 

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Anyone know how much time or range the F-22s spend in supercruise?
At what altitude? No one will answer that question but based on readings here and at f-16.net I think I recall only 150 miles for some mission profiles to maximize overall range. Its not exactly Firefox is it. It can probably run the tanks dry at m1.6 without hurting anything.
 

Dragon029

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There's no publicly available word on any limits the jet can spend in supercruise, but we do have this chart:

1624067568823.png

In that chart it's saying that an F-22 (without external fuel tanks) flying at subsonic speeds has a combat radius of 590 nautical miles, while "With 100 nm Supercruise" the combat radius drops to about 460 nautical miles, for a combat radius decrease of 130 nautical miles / a total range decrease of 260 nautical miles.

In my opinion this sounds like they're saying 100 nautical miles of supercruise in total, which would mean that an F-22 burns about 2.6x as much fuel supercruising / at full mil power than when subsonic cruising. That would therefore limit the F-22's maximum amount of supercruise flight (during a 1-way trip) to something in the ballpark of 300, maybe 350 nautical miles.

If I'm wrong about that initial assumption and the F-22 flies 100nmi in supercruise each way from the target (for 200nmi total) then it burns about 1.3x as much fuel, though frankly that seems unlikely as (ignoring the non-static and non-linear relationship of Mach and drag coefficient) drag increases with the square of airspeed, so supercruising at Mach 1.5-1.8 (the higher end being roughly 2x what it'd normally subsonic cruise at) should require something like 4x the thrust. The relationship between thrust and fuel consumption is also non-linear and but too complex for me to really take an estimate at, but it's fair to say that 2.6x the fuel burn is more realistic than 1.3x.
 

Bruno Anthony

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There's no publicly available word on any limits the jet can spend in supercruise, but we do have this chart:

View attachment 659223

In that chart it's saying that an F-22 (without external fuel tanks) flying at subsonic speeds has a combat radius of 590 nautical miles, while "With 100 nm Supercruise" the combat radius drops to about 460 nautical miles, for a combat radius decrease of 130 nautical miles / a total range decrease of 260 nautical miles.

In my opinion this sounds like they're saying 100 nautical miles of supercruise in total, which would mean that an F-22 burns about 2.6x as much fuel supercruising / at full mil power than when subsonic cruising. That would therefore limit the F-22's maximum amount of supercruise flight (during a 1-way trip) to something in the ballpark of 300, maybe 350 nautical miles.

If I'm wrong about that initial assumption and the F-22 flies 100nmi in supercruise each way from the target (for 200nmi total) then it burns about 1.3x as much fuel, though frankly that seems unlikely as (ignoring the non-static and non-linear relationship of Mach and drag coefficient) drag increases with the square of airspeed, so supercruising at Mach 1.5-1.8 (the higher end being roughly 2x what it'd normally subsonic cruise at) should require something like 4x the thrust. The relationship between thrust and fuel consumption is also non-linear and but too complex for me to really take an estimate at, but it's fair to say that 2.6x the fuel burn is more realistic than 1.3x.
Great stuff. But wouldn’t fuel consumption at 2.6x the Mach 0.9 rate make a full supercruise radius about 240nmi? 240x2.6~600

Also any idea what the fuel consumption is at full AB? To compare it to supercruise to see if supercruise is a more economical setting?

Sounds like the story where Lockheed told the AF, “we can give you stealth, supercruise and range!“ Pick any 2.

Does show how clean the F-22 airframe is compared to the F-15. Impressive.
 

_Del_

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Does show how clean the F-22 airframe is compared to the F-15. Impressive.
It's less about the aerodynamic qualities between the two, and more about the 30% routing factor attributed to the Beagles. Which in the real world still makes quite a difference and is impressive.
It's not the aerodynamic efficiency of the Raptor creating that difference in mission radius, though.
If you add that third back to the Beagle, the straight line range is going to favour the Beagle with tanks over the Raptor (the Beagle is also carrying two 2,000 lb LGB + four AMRAAM, and not the Raptor's two 1,000 lb LGB's, two AMRAAM, and two Sidewinders loadout in the graph). It'd be 750 straight line for Beagle in that configuration to 600 for the Raptor, or 300 miles farther traveled with bombs twice the size.

The advantage is in the mission planning being able to draw smaller threat bubbles around targets, and a much straighter run at altitude (HHHH profile) compared to a circuitous route by the HLLH Beagle making the mid portion of the flight down low.

It's misleading in some sense, but absolutely not in another sense. It's a very precise scenario depicted which requires a Beagle to avoid an integrated air defense -- which is a very real scenario in which a Raptor holds a significant advantage. The flip side is that the Beagle against a lower threat threshold is going to haul more iron to targets quite a bit farther away than a clean F-22 could.
 

Dragon029

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Great stuff. But wouldn’t fuel consumption at 2.6x the Mach 0.9 rate make a full supercruise radius about 240nmi? 240x2.6~600

Also any idea what the fuel consumption is at full AB? To compare it to supercruise to see if supercruise is a more economical setting?

Sounds like the story where Lockheed told the AF, “we can give you stealth, supercruise and range!“ Pick any 2.

Does show how clean the F-22 airframe is compared to the F-15. Impressive.
I believe you're correct with 240nmi; I was using a bit of a convoluted calculation.

As for max afterburner; the TSFC for the F119 at a supersonic cruising altitude and Mach is classified, but at least down at sea level and zero airspeed, most turbofan engines have a TSFC of roughly 2lb/lbf*hr. The F119's actual max afterburner thrust isn't public, and it too will vary based on airspeed and altitude, but if we take the sea level rating of "35,000+" lbf as just 35K (70K for 2 engines) then that equates to 2333lb/min fuel burn for the jet in total.

Because we're not talking about fuel burn per unit of time vs fuel burn per unit of distance, things get tricky because the time to accelerate to certain speeds affects things. To demonstrate that supercruise is still more economic however, I'll give afterburner the benefit of the doubt and say the jet has an average flight regime of Mach 1.8, at 50,000ft (for a TAS of 1032kts). I'm going to assume that the reserve fuel for the mission profile mentioned above is 2000lb and that the 6% routing factor still applies.

So with 16,000lb of usable fuel, we can use our afterburner for 6.9 minutes, which at 1032nmi/hr or 17.2nmi/min, divided by 1.06 for routing factor, gives it a total 100% max afterburner combat range of 112nmi or radius of just 56nmi.

Now again, these numbers aren't particularly accurate as the TSFC and thrust produced by the engine changes based on airspeed and altitude, but you can nevertheless see how extreme fuel burn rates get at max afterburner, and I think it's fair to say that even with the limited accuracy, supercruise is definitely a more economical settings. It just goes to show how powerful these jet engines can be, and it goes to show the ballpark advantage that supercruise gets you, at least on the F-22 (roughly double the time / distance spent at a significant Mach speed).

It's worth noting some other assumptions however - the 2.6x fuel consumption assumes that zero afterburner is used in that F-22 mission profile, getting it up to supercruise speeds. We also don't know what the average supercruise speed is; the max supercruise speed of roughly Mach 1.8 is awesome, but 100nmi doesn't leave you a lot of time to reach it, so the average supercruise speed might have only been something like Mach 1.4. The mission profile might also possibly not demand 100% mil power, but just whatever assumed throttle is required to achieve a top supercruise airspeed of Mach 1.5 (one of the early F-22 supercruise top speed claims before the USAF kept elaborating on just how fast it could go).

In any case, supercruise is definitely useful and more economical than afterburner, but it's certainly not something that's easy to sustain without serious range penalties.
 

Firefinder

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It's worth noting some other assumptions however - the 2.6x fuel consumption assumes that zero afterburner is used in that F-22 mission profile, getting it up to supercruise speeds. We also don't know what the average supercruise speed is; the max supercruise speed of roughly Mach 1.8 is awesome, but 100nmi doesn't leave you a lot of time to reach it, so the average supercruise speed might have only been something like Mach 1.4. The mission profile might also possibly not demand 100% mil power, but just whatever assumed throttle is required to achieve a top supercruise airspeed of Mach 1.5 (one of the early F-22 supercruise top speed claims before the USAF kept elaborating on just how fast it could go).
Then you have the reserve fuel for actually fighting and back up.

Either in getting posistion to launch a weapon to turning and burning dogfights or jinking and jiving around SAMS. Which supercruiser will be useful for short sprints in those situations. A few seconds at most, basically replacing the need for the afterburn for the most part.

Which is very handly maintance wise.
 

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Compared to Riccioni’s idea of a supercruise fighter with a .40 Fuel Fraction and time of at least 20 mins in supercruise, how close does the Raptor come to his definition?
Say flying at 1000mph for 20 mins total is about 340 miles with 170 miles each way. Raptor seems a bit short. The Raptor is also more capable than anything he planned.
 

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It's 100nm segment of the radius, i.e. its 330nm + 100nm sub + super combat radius on the now defunct official F-22 webpage that LM had up until a few years ago. I suspect that it's somewhat understated. There was an interview with a USAF GO who stated that in the anti-cruise missile mission, the F-22 could maintain M1.5 for 41 minutes vice 7 minutes for the Eagle (AW&ST June 12, 2006). This is somewhat backed up by a demonstration by HO Raptors around that time that went M1.5 from HO to the UTTR to drop JDAMs then recover at Hill AFB. HO to UTTR is 600nm.

I believe the ballpark figure for rough average Specific Range at M1.5 is around 0.045 to 0.0475 nm/lb of fuel. I believe that the SR is around 0.1 nm/lb at M 0.9. Using the rough 2/3rds rule of thumb, that would suggest cruise fuel of roughly 12Klbs. 150nm transit to and from the tanker tracks might enable the Raptor to go 150nm + ~200nm super in this case. The Raptor didn't meet the original ATF or even revised ATF supercruise spec but has way more supersonic persistence than anything else out there sans the Su-57 or J-20.
 

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The Raptor didn't meet the original ATF or even revised ATF supercruise spec but has way more supersonic persistence than anything else out there sans the Su-57 or J-20.
J-20 is kinda questionable here. It is neither aerodynamically refined to be noticeable nor big enough/has fuel fraction big enough/having engines advanced enough to be really noticeable over other heavy fighters. Internal weapons help with that but only to a degree.
 

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It's 100nm segment of the radius, i.e. its 330nm + 100nm sub + super combat radius on the now defunct official F-22 webpage that LM had up until a few years ago. I suspect that it's somewhat understated. There was an interview with a USAF GO who stated that in the anti-cruise missile mission, the F-22 could maintain M1.5 for 41 minutes vice 7 minutes for the Eagle (AW&ST June 12, 2006). This is somewhat backed up by a demonstration by HO Raptors around that time that went M1.5 from HO to the UTTR to drop JDAMs then recover at Hill AFB. HO to UTTR is 600nm.

I believe the ballpark figure for rough average Specific Range at M1.5 is around 0.045 to 0.0475 nm/lb of fuel. I believe that the SR is around 0.1 nm/lb at M 0.9. Using the rough 2/3rds rule of thumb, that would suggest cruise fuel of roughly 12Klbs. 150nm transit to and from the tanker tracks might enable the Raptor to go 150nm + ~200nm super in this case. The Raptor didn't meet the original ATF or even revised ATF supercruise spec but has way more supersonic persistence than anything else out there sans the Su-57 or J-20.
Based on the numbers you gave sounds like ~600 nmi RANGE at M1.5. M1.5 for ~40 mins is about 600 nmi as is ~.05 nmi/lb of fuel in supercruise. 12,000(.05)=600. 300 nmi supercruise RADIUS. Not too shabby.

Now it didn’t meet the specs which were iirc 400 nmi supercruise radius because they:
didn‘t want to keep adding fuel weight?
 

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There's no publicly available word on any limits the jet can spend in supercruise, but we do have this chart:

View attachment 659223

In that chart it's saying that an F-22 (without external fuel tanks) flying at subsonic speeds has a combat radius of 590 nautical miles, while "With 100 nm Supercruise" the combat radius drops to about 460 nautical miles, for a combat radius decrease of 130 nautical miles / a total range decrease of 260 nautical miles.

In my opinion this sounds like they're saying 100 nautical miles of supercruise in total, which would mean that an F-22 burns about 2.6x as much fuel supercruising / at full mil power than when subsonic cruising. That would therefore limit the F-22's maximum amount of supercruise flight (during a 1-way trip) to something in the ballpark of 300, maybe 350 nautical miles.

If I'm wrong about that initial assumption and the F-22 flies 100nmi in supercruise each way from the target (for 200nmi total) then it burns about 1.3x as much fuel, though frankly that seems unlikely as (ignoring the non-static and non-linear relationship of Mach and drag coefficient) drag increases with the square of airspeed, so supercruising at Mach 1.5-1.8 (the higher end being roughly 2x what it'd normally subsonic cruise at) should require something like 4x the thrust. The relationship between thrust and fuel consumption is also non-linear and but too complex for me to really take an estimate at, but it's fair to say that 2.6x the fuel burn is more realistic than 1
What happened to the 750nm atf requirement?
To me that chart tells me a beagle with 3 bags is hauling an assload of fuel for not much benefit.
 

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It's 100nm segment of the radius, i.e. its 330nm + 100nm sub + super combat radius on the now defunct official F-22 webpage that LM had up until a few years ago.
I don't follow your grammar there; what is the 330nmi (super or subsonic), why is 100nmi subsonic (when the chart above is saying 100nmi of supercruise) and what is the "super combat radius" you're adding to those numbers?

There was an interview with a USAF GO who stated that in the anti-cruise missile mission, the F-22 could maintain M1.5 for 41 minutes vice 7 minutes for the Eagle (AW&ST June 12, 2006)
If that's true (I don't have a subscription to access the archive) then a lot of the numbers surrounding the F-22's range must be wrong (a subsonic specific range of 0.1lb/nmi for example would yield a subsonic combat radius roughly 30% longer than the published figure); traveling ~66-75% faster while burning only ~100% extra fuel, especially when you're breaking the sound barrier and having to actually accelerate up to those speeds doesn't seem feasible.

What happened to the 750nm atf requirement?
The F-22 achieves that with a pair of bags.
 

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It's 100nm segment of the radius, i.e. its 330nm + 100nm sub + super combat radius on the now defunct official F-22 webpage that LM had up until a few years ago.
I don't follow your grammar there; what is the 330nmi (super or subsonic), why is 100nmi subsonic (when the chart above is saying 100nmi of supercruise) and what is the "super combat radius" you're adding to those numbers?

There was an interview with a USAF GO who stated that in the anti-cruise missile mission, the F-22 could maintain M1.5 for 41 minutes vice 7 minutes for the Eagle (AW&ST June 12, 2006)
If that's true (I don't have a subscription to access the archive) then a lot of the numbers surrounding the F-22's range must be wrong (a subsonic specific range of 0.1lb/nmi for example would yield a subsonic combat radius roughly 30% longer than the published figure); traveling ~66-75% faster while burning only ~100% extra fuel, especially when you're breaking the sound barrier and having to actually accelerate up to those speeds doesn't seem feasible.

What happened to the 750nm atf requirement?
The F-22 achieves that with a pair of bags.
 

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BDF

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It's 100nm segment of the radius, i.e. its 330nm + 100nm sub + super combat radius on the now defunct official F-22 webpage that LM had up until a few years ago.
I don't follow your grammar there; what is the 330nmi (super or subsonic), why is 100nmi subsonic (when the chart above is saying 100nmi of supercruise) and what is the "super combat radius" you're adding to those numbers?

There was an interview with a USAF GO who stated that in the anti-cruise missile mission, the F-22 could maintain M1.5 for 41 minutes vice 7 minutes for the Eagle (AW&ST June 12, 2006)
If that's true (I don't have a subscription to access the archive) then a lot of the numbers surrounding the F-22's range must be wrong (a subsonic specific range of 0.1lb/nmi for example would yield a subsonic combat radius roughly 30% longer than the published figure); traveling ~66-75% faster while burning only ~100% extra fuel, especially when you're breaking the sound barrier and having to actually accelerate up to those speeds doesn't seem feasible.

What happened to the 750nm atf requirement?
The F-22 achieves that with a pair of bags.

The website listed "Mission 1" combat radius with the objective and achieved in testing. I can't recall the exact objective but I want to say it was ~275nm subsonic segment plus a 100nm supersonic segment. The achieved was 310nm subsonic (I made a typo in my previous post) and 100nm supersonic segments. For a total combat radius of 410nm.

I'm not sure I'd agree that SR is around 0.07 nm/lb (30% less.) That F-22 slide shows roughly 590nm subsonic combat radius. A good rule of thumb for cruise fuel for making a rough combat radius calculation is 67% of max fuel (depending on the mission set but its a rough guide). In this case that's roughly 12,000lbs. 1180/12000 = 0.0983 nm/lb. A 0.07 nm/lb would require 16,850lb which would either require more fuel than the Raptor is said to have or eating into other sections of the fuel score. I don't think it's correct simply because standard VFR recovery reserves is 14% which gives you remaining fuel of 15,500lbs for everything else (STTO, Climb, Cruise, Combat & Descent.) I'm happy to be corrected (my recollection of that AvWeek article was in error) but I'm fairly certain that I'm in the ballpark. In anycase I come up with a 2.1:1 ratio of supersonic to subsonic cruise SR.
 
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Bruno Anthony

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It's 100nm segment of the radius, i.e. its 330nm + 100nm sub + super combat radius on the now defunct official F-22 webpage that LM had up until a few years ago.
I don't follow your grammar there; what is the 330nmi (super or subsonic), why is 100nmi subsonic (when the chart above is saying 100nmi of supercruise) and what is the "super combat radius" you're adding to those numbers?

There was an interview with a USAF GO who stated that in the anti-cruise missile mission, the F-22 could maintain M1.5 for 41 minutes vice 7 minutes for the Eagle (AW&ST June 12, 2006)
If that's true (I don't have a subscription to access the archive) then a lot of the numbers surrounding the F-22's range must be wrong (a subsonic specific range of 0.1lb/nmi for example would yield a subsonic combat radius roughly 30% longer than the published figure); traveling ~66-75% faster while burning only ~100% extra fuel, especially when you're breaking the sound barrier and having to actually accelerate up to those speeds doesn't seem feasible.

What happened to the 750nm atf requirement?
The F-22 achieves that with a pair of bags.

The website listed "Mission 1" combat radius with the objective and achieved in testing. I can't recall the exact objective but I want to say it was ~275nm subsonic segment plus a 100nm supersonic segment. The achieved was 310nm subsonic (I made a typo in my previous post) and 100nm supersonic segments. For a total combat radius of 410nm.

I'm not sure I'd agree that SR is around 0.07 nm/lb (30% less.) That F-22 slide shows roughly 590nm subsonic combat radius. A good rule of thumb for cruise fuel for making a rough combat radius calculation is 67% of max fuel (depending on the mission set but its a rough guide). In this case that's roughly 12,000lbs. 1180/12000 = 0.0983 nm/lb. A 0.07 nm/lb would require 16,850lb which would either require more fuel than the Raptor is said to have or eating into other sections of the fuel score. I don't think it's correct simply because standard VFR recovery reserves is 14% which gives you remaining fuel of 15,500lbs for everything else (STTO, Climb, Cruise, Combat & Descent.) I'm happy to be corrected (my recollection of that AvWeek article was in error) but I'm fairly certain that I'm in the ballpark. In anycase I come up with a 2.1:1 ratio of supersonic to subsonic cruise SR.
 

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BDF

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@Bruno Anthony

Not sure why you're reposting this as a response to what I said to Dragon. As I stated at the end of the last paragraph:

I'm happy to be corrected (my recollection of that AvWeek article was in error) but I'm fairly certain that I'm in the ballpark. In any case I come up with a 2.1:1 ratio of supersonic to subsonic cruise SR.
 

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@Bruno Anthony

Not sure why you're reposting this as a response to what I said to Dragon. As I stated at the end of the last paragraph:

I'm happy to be corrected (my recollection of that AvWeek article was in error) but I'm fairly certain that I'm in the ballpark. In any case I come up with a 2.1:1 ratio of supersonic to subsonic cruise SR.
Not sure if you read the article I originally posted. Not everyone has access to AvWeek archive so I screenshot relevant articles.
 

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there was some news earlier this week about Hawaiian F-22s being scrambled to intercept Russian aircraft.

Since Hawaii is really quite far from Russia, I am wondering what the flight path of these aircraft would be like.
would they depart from Kamchatka or something and fly for like 6-8 hours south then turn around after the interception?
 

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