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USAF/US NAVY 6th Generation Fighter Programs - F/A-XX, F-X, NGAD, PCA

bobbymike

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I know the story has been already told with the Tomcat, but a Super C (F-35) will probably meet most of the urgent needs post 30's.
Question for the aero-engineers out there. Take the F-35C and modify for two engines. Like a naval F-22? Total waste of time? Might as well develop a whole new airframe?
 

jsport

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I know the story has been already told with the Tomcat, but a Super C (F-35) will probably meet most of the urgent needs post 30's.
The test of the F-35 verses the A-10 displayed the F-35 can not fight low low altit w/ high weight external stores.
 

In_A_Dream

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Question for the aero-engineers out there. Take the F-35C and modify for two engines. Like a naval F-22? Total waste of time? Might as well develop a whole new airframe?
Since the United States military is fully committed to the F-35, it's best to pray the 6th gen carrier a/c will fulfill future needs.. The USG knew the threat China posed as far back as the 90s but instead chose to indulge in the Global War on Terror for close to 20 years. They made their bed, now they can lay in it.
 

TomS

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"Modify for two engines" = all new aircraft.
 

Dragon029

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You could reuse the same avionics and a good number of vehicle systems, but structurally you'd have to nearly start from scratch.
 

TomcatViP

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80klb of thrust is a lot for an airframe the size of a F-35.
I personally don't understand this quest for a second engine when one suffice and make for a more reliable propulsion unit.
Every fighter need more thrust however. I agree with that. But that will be third stream, a more efficient engine designed to be swap without any major rework.
To me a Super C would only be slightly longer to hall more fuel and/or offering more internal volume for weapons keeping the same enlarged wing. Max lift (bring back weight) would be increased with collapsible mustaches or other aero refinement.
 

GARGEAN

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Real Super C should be at least 1.2 times the size or just have new and bigger airframe. At the very least for mounting more internal weapons.
 

NeilChapman

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Question for the aero-engineers out there. Take the F-35C and modify for two engines. Like a naval F-22? Total waste of time? Might as well develop a whole new airframe?
Since the United States military is fully committed to the F-35, it's best to pray the 6th gen carrier a/c will fulfill future needs.. The USG knew the threat China posed as far back as the 90s but instead chose to indulge in the Global War on Terror for close to 20 years. They made their bed, now they can lay in it.
Pray as though everything depends on God. Work as though everything depends on you. My sense is that the work is being done.
Maybe a USAF solution will be first, though? We'll see.

Tech is changing so quickly, hypersonics, etc. SpaceX will likely have 1200 additional satellites up each of the next five years. SpaceX expects to have Starship on the moon be mid decade. That's 100 tons into space with each launch.

No one will be lying down. Too many exciting things happening.
 

jsport

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80klb of thrust is a lot for an airframe the size of a F-35.
I personally don't understand this quest for a second engine when one suffice and make for a more reliable propulsion unit.
Every fighter need more thrust however. I agree with that. But that will be third stream, a more efficient engine designed to be swap without any major rework.
To me a Super C would only be slightly longer to hall more fuel and/or offering more internal volume for weapons keeping the same enlarged wing. Max lift (bring back weight) would be increased with collapsible mustaches or other aero refinement.
understand maintainability, reliablity and thrust of a single engine in nexgen however two is faster:D Fuel efficiency would allow a longer legs and a large bay on craft the size of an F-14. Will mustaches give you the low low lift and control of a genuine swinger?
 

Colonial-Marine

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I don't know if variable sweep is really necessary (although it would definitely be really cool) but I do think a large twin-engine strike fighter is called for. Engine could be some AETP derivative roughly F119 sized.

I simply don't see how you could possibly turn the F-35C into that.
 

TomcatViP

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understand maintainability, reliablity and thrust of a single engine in nexgen however two is faster:D Fuel efficiency would allow a longer legs and a large bay on craft the size of an F-14. Will mustaches give you the low low lift and control of a genuine swinger?
You are right, modern Variable geometry will certainly be at best to offer the low lift that is needed.
 

kaiserd

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understand maintainability, reliablity and thrust of a single engine in nexgen however two is faster:D Fuel efficiency would allow a longer legs and a large bay on craft the size of an F-14. Will mustaches give you the low low lift and control of a genuine swinger?
You are right, modern Variable geometry will certainly be at best to offer the low lift that is needed.
One always wants “low lift”, the lower the better, apparently.....
Is this intended as a reference to low drag and/ or high wing-loading and/or low-gust response?
 

jsport

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understand maintainability, reliablity and thrust of a single engine in nexgen however two is faster:D Fuel efficiency would allow a longer legs and a large bay on craft the size of an F-14. Will mustaches give you the low low lift and control of a genuine swinger?
You are right, modern Variable geometry will certainly be at best to offer the low lift that is needed.
One always wants “low lift”, the lower the better, apparently.....
Is this intended as a reference to low drag and/ or high wing-loading and/or low-gust response?
higher lift at low altitude,,, jeepers creepers
 

kaiserd

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understand maintainability, reliablity and thrust of a single engine in nexgen however two is faster:D Fuel efficiency would allow a longer legs and a large bay on craft the size of an F-14. Will mustaches give you the low low lift and control of a genuine swinger?
You are right, modern Variable geometry will certainly be at best to offer the low lift that is needed.
One always wants “low lift”, the lower the better, apparently.....
Is this intended as a reference to low drag and/ or high wing-loading and/or low-gust response?
higher lift at low altitude,,, jeepers creepers
Swing wings don’t give higher lift at low altitude . They allow a combination of lower drag and higher-wing loading (hence lower gust-response) for low altitude high speed penetration (with wings swept back) than would would the case for a comparable fixed wing if you are looking to combine it with other performance parameters like short-field / short take-off and landing, and/ or high altitude sub-sonic cruise performance/ range (with wings swept forward). There are no absolutes in this; for example blown flaps on a fixed wing could give limit some of this performance (like the F-111 versus the TSR2, for example), while given a specific requirement (for example for the Tornado) the swing wing (despite the inbuilt weight penalty of the swing mechanism) can still be the most efficient solution.
 

jsport

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understand maintainability, reliablity and thrust of a single engine in nexgen however two is faster:D Fuel efficiency would allow a longer legs and a large bay on craft the size of an F-14. Will mustaches give you the low low lift and control of a genuine swinger?
You are right, modern Variable geometry will certainly be at best to offer the low lift that is needed.
One always wants “low lift”, the lower the better, apparently.....
Is this intended as a reference to low drag and/ or high wing-loading and/or low-gust response?
higher lift at low altitude,,, jeepers creepers
Swing wings don’t give higher lift at low altitude . They allow a combination of lower drag and higher-wing loading (hence lower gust-response) for low altitude high speed penetration (with wings swept back) than would would the case for a comparable fixed wing if you are looking to combine it with other performance parameters like short-field / short take-off and landing, and/ or high altitude sub-sonic cruise performance/ range (with wings swept forward). There are no absolutes in this; for example blown flaps on a fixed wing could give limit some of this performance (like the F-111 versus the TSR2, for example), while given a specific requirement (for example for the Tornado) the swing wing (despite the inbuilt weight penalty of the swing mechanism) can still be the most efficient solution.
Wider span the more lift at any altitude but the more wing the more drag.
 

Sundog

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The purpose of lift in cruise is to counteract the weight In cruise. If you want low lift, you had better have low weight. Aerodynamically speaking, VG would be optimum, but VG makes signature control more difficult and increases cost and complexity. While blown flaps on a fixed wing can help increase lift at low speeds, it still isn’t as good a solution as VG.

One of the reasons VG isn’t as in demand as it used to be is most recent aircraft have been designed to maximum Mach numbers around 1.8. That helps keep the materials standard, as opposed to the more exotic materials one has to use to deal with in the thermal environment above 1.8. That, plus no longer requiring high speed on the deck (High maximum q), means that VG doesn’t have as much of an advantage over a fixed wing design. Also, it should be noted that lift devices on high speed fixed wings have also improved over time, such as the advent of vortex flaps.
 

dark sidius

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F-15 EX have not a lot to see with next generation air dominance, more a back to past , is it an echec for the stealth technology in fact ? I have the feeling that we are not soon to see something realy new in the fighter game.
 
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bobbymike

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rooster

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2000 mile range sounds like a big plane like pca. Why can't the usaf and usn commonize like the f35?
 

VTOLicious

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2000 mile range sounds like a big plane like pca. Why can't the usaf and usn commonize like the f35?
Out of interest: Is the F-15E's 687nmi (1272km) combat radius including the CFT's?
 

dark sidius

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1 billion for USAF ngad its a good amount of money, surely some prototype will flying in a near futur with this level of funding.
 

jsport

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FleetDefense can be accomplished by short range USN only UCRAVS all other USAF USN missions overlap.
NGAD PCA are about politics unfortunately not the technology.
A real vision would be best for the most number of manufactures and the US industrial base writ large.
examples of possible optionally manned craft

1. LF/RF DEW fighter/gunship w/ Air Superiority capability
2. EW/Cyber W fighter w/ Air Superiority capability
3. Offensive/Defensive (Ground/Air) Cannon fighter w/ Air Superiority capability
4. ultra low altitude maneuver fighter/cruise missile def/penetrator w/ Air Superiority capability
5. ultra high altitude fighter/BMD/interceptor/penetrator w/ Air Superiority capability
6. UAS mothership (armed UASs don't return to the nest leading the adversary like that dumb Gremlins program) w/ Air Superiority capability
7. CAS medium altitude fighter/gunship
8. CAS low altitude missile & gunship fighter
9. FA-XX multi-purpose medium missile carrier w/ Air Superiority capabilityw/ Air Superiority capability
10. FB-XX bomber/cruise missile/hypersonic multi-purpose missile carrier
11. Penetrating Surveillance fighter w/a large top mounted AESA "canoe" and a bottom mounted AESA "canoe" wide area hyperspectral/IR/EO (even small IR event geolocation) w/ Air Superiority capability
12. Maneuverable VTOL w/ 4-6 person cabin for in extremis infil or exfil w/ limited CAS, BAI w/ Air Superiority capability
 

rooster

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2000 mile range sounds like a big plane like pca. Why can't the usaf and usn commonize like the f35?
Because they aren't flying the same mission.
To be simplistic, stealth, long range + supercruise are on order for both. With hobs missiles and an end of the turning airfight, why can't a common airframe with different avionics and perhaps wings work? Simplistically the tomcat could have served both branches, not ideal, but could have been done. How different are the missions?
 

Sundog

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2000 mile range sounds like a big plane like pca. Why can't the usaf and usn commonize like the f35?
Because they aren't flying the same mission.
To be simplistic, stealth, long range + supercruise are on order for both. With hobs missiles and an end of the turning airfight, why can't a common airframe with different avionics and perhaps wings work? Simplistically the tomcat could have served both branches, not ideal, but could have been done. How different are the missions?
Because the USAF, now, is usually looking for an aircraft that can super cruise deep into enemy territory, fight, then super cruise back. Whereas the Navy generally wants an aircraft that can fly to a specific point a couple of hundred miles from the carrier, then loiter, while making sure the air space around the carrier is secure. The ranges required are generally different as well. That means you have one aircraft optimized for supersonic cruise and one aircraft optimized for subsonic loitering with a supersonic burst capability. This results in aircraft in markedly different sizes and aerodynamic characteristics. Also, the USAF does not want the weight penalties that come with an aircraft designed for carrier ops.

This is why the USAF and the Navy have talked about sharing systems and possibly different versions of the same power plant, but that's it.

It's interesting that you referenced the Tomcat, because the Tomcat could not perform the Eagles mission and the Eagle couldn't perform the Tomcat's mission. In fact, when the USAF started developing the F-X (What became the F-15), they were originally VG designs. One of the reasons they switched to a fixed wing was they were afraid congress would be unable to tell the difference between the two and they would be ordered to buy the F-14, with all of it's inherent Navy limitations forced upon the USAF. The mission defines the aircraft, not the other way around.
 

totoro

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Out of interest: Is the F-15E's 687nmi (1272km) combat radius including the CFT's?
Don't know about F-15E, but here are some F-15C figures, which might help. USAF's figures from the standard aircraft characteristics document.
F-15C, with 4 sparrows, 2 Mk84 bombs and one centerline tank, retained:
Without CFT - radius 551 nm
With CFTs - radius 836 nm
 

dark sidius

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Its clear that the futur fighter will have adaptive engine, 1.4 Billion in 2021 for NGAD technology big part of money.
 

rooster

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2000 mile range sounds like a big plane like pca. Why can't the usaf and usn commonize like the f35?
Because they aren't flying the same mission.
To be simplistic, stealth, long range + supercruise are on order for both. With hobs missiles and an end of the turning airfight, why can't a common airframe with different avionics and perhaps wings work? Simplistically the tomcat could have served both branches, not ideal, but could have been done. How different are the missions?
Because the USAF, now, is usually looking for an aircraft that can super cruise deep into enemy territory, fight, then super cruise back. Whereas the Navy generally wants an aircraft that can fly to a specific point a couple of hundred miles from the carrier, then loiter, while making sure the air space around the carrier is secure. The ranges required are generally different as well. That means you have one aircraft optimized for supersonic cruise and one aircraft optimized for subsonic loitering with a supersonic burst capability. This results in aircraft in markedly different sizes and aerodynamic characteristics. Also, the USAF does not want the weight penalties that come with an aircraft designed for carrier ops.

This is why the USAF and the Navy have talked about sharing systems and possibly different versions of the same power plant, but that's it.

It's interesting that you referenced the Tomcat, because the Tomcat could not perform the Eagles mission and the Eagle couldn't perform the Tomcat's mission. In fact, when the USAF started developing the F-X (What became the F-15), they were originally VG designs. One of the reasons they switched to a fixed wing was they were afraid congress would be unable to tell the difference between the two and they would be ordered to buy the F-14, with all of it's inherent Navy limitations forced upon the USAF. The mission defines the aircraft, not the other way around.
I don't know what limitations the air force would have endured with a hypothetical tomcat instead of eagle in its ranks. Both were designed after lessons from Vietnam and the mantra of not a pound for air to ground.

The tomcat was a turkey because of engines and a poorly executed and complicated hydraulic system that made it a hangar queen. But had it been executed better, it could have met both services needs for air supremacy.

The phantom did fine serving in all 3 of our air forces.

So again, both services need a long ranged supercruiser with all aspect stealth that can either fly from runway or a catapult and provide air dominance. How are the requirements contradictory to each other? This isn't 1984 and budgets are limited. I think they could or should compromise and build a common platform.

Example: Northrop natf which has a model on a pole in St Louis. Looks like a fine aircraft for either branch. But I'm not a aeronautical engineer.

The f35 is what it is because of the marines and Britain's want for stovl. That really limited things with the f35 and made it chunky since all the weapons had to go into the sides and not in centerline weapons bay because of the lift fan variant of the jet.
 

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I don't know what limitations the air force would have endured with a hypothetical tomcat instead of eagle in its ranks. Both were designed after lessons from Vietnam and the mantra of not a pound for air to ground.

The tomcat was a turkey because of engines and a poorly executed and complicated hydraulic system that made it a hangar queen. But had it been executed better, it could have met both services needs for air supremacy.

The phantom did fine serving in all 3 of our air forces.

So again, both services need a long ranged supercruiser with all aspect stealth that can either fly from runway or a catapult and provide air dominance. How are the requirements contradictory to each other? This isn't 1984 and budgets are limited. I think they could or should compromise and build a common platform.

Example: Northrop natf which has a model on a pole in St Louis. Looks like a fine aircraft for either branch. But I'm not a aeronautical engineer.

The f35 is what it is because of the marines and Britain's want for stovl. That really limited things with the f35 and made it chunky since all the weapons had to go into the sides and not in centerline weapons bay because of the lift fan variant of the jet.
What it comes down to is you simply don't understand how aircraft are designed. It's that simple. The mission defines the aircraft, not the other way around.

The F-35 is a poor example because all of the services made massive changes to their original mission requirements to make one basic airframe compatible for all of the services. You will notice that it, just like the F-16, will be used more as a strike aircraft than the classic air superiority mission. It has a very good self defense capability, but since this programs inception decades ago, many have come to the conclusion that actually developing separate airframes for the different services using the same systems may have been the lower cost route to go.

Here's a good reference for you to educate yourself regarding mission profile definitions. Note, that's a link to a PDF.

BTW, your reference to the Northrop NATF was a good example of what I am talking about. You will note that it was a substantially different design, as in completely different, to their ATF airframe, the YF-23. This was due to the very different mission requirements for the two services.

The F-4 is something of an outlier, because both services were looking for an all weather missile interceptor to go against Russian bombers, so their mission requirements were in line with each other. However, the Air Force still paid a penalty in having the Phantom, by having to add a drag chute due to the naval landing gear requirements (MLG to CG geometry) and the heavier weight required to meet the Navy's requirements.

BTW, if you really want to learn about aircraft design, I can't recommend this book enough. Aircraft Design: A conceptual Approach by Dan Raymer. You can find a PDF version of an early edition online, but I recommend the book. Anyone interested in aircraft design should have this book on their book shelf.

I wish it had been available when I was studying Aeronautical Engineering. "Back in my day..." we only had the professors notes and snippets from various books to put the pieces together. There were Roskam's books (Too many errors to sift through, although I wish I could remember which volume had all of the engine decks in it). Having said that, you don't have to be an Aeronautical Engineer to understand the basic concepts in this, Raymer's, book. It's easily accessible to anyone, since it it's about the how of it more so then all of the mathematical details you get in specific Aero Engineering courses.
 
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There is a paradox today that makes airframe design much less costly than it was before, turning service request for modifications (given that they are extensive) nearly as expensive as designing two different airframe.

Back in the days of the Phantom, extensive design, integration and test work made easier to start with a shared base. Most design at the time were slight evolution of earlier airframe (see MCDD history of fighters for example).
 

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TAOG

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Lockheed shows their six generation fighter at AWS20.

7695e2e2ly1gcabr269cuj20mq0p00w7.jpg
 
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TAOG

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It looks similar to their 2017 model, where the PCA concept still existed.

7695e2e2ly1gcabr26kcaj20sg0g2tbi.jpg
 
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