USAF/US NAVY 6G Fighter Programs - F/A-XX, F-X, NGAD, PCA, ASFS news

If I were a betting man, I would say it’s shape looks like this:
 

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If I were a betting man, I would say it’s shape looks like this:
No need to bet as it's very old patch with a stylized NASA/Lockheed REVCON/IСE/FATE concept planform
 

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If I were a betting man, I would say it’s shape looks like this:
No need to bet as it's very old patch with a stylized NASA/Lockheed REVCON/IСE/FATE concept planform

Yep. I would expect something like Lockheed's ICE to be the basis for a full scale demonstrator.
There's been a large revival of work on it in recent years including the NATO AVT-239 Task Group
looking at active flow control effectors. Active control flow has been regarded as a good use
for the third stream in an adaptive engine.


ice-model.png

https://scholarworks.wmich.edu/cgi/viewcontent.cgi?article=5350&context=masters_theses
 

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Yep. I would expect something like Lockheed's ICE to be the basis for a full scale demonstrator.

IOW the manned component might very well end up looking like a flying masonry trowel. I do wonder if the inlets will still be mounted on the bottom or be moved to the top as some contractor/service images have suggested. I know that mounting the inlet on top is preferable LO wise but would be a PITA from airflow management on a fighter; even if AoA requirements are much less than today's jets.
 
Yep. I would expect something like Lockheed's ICE to be the basis for a full scale demonstrator.

IOW the manned component might very well end up looking like a flying masonry trowel. I do wonder if the inlets will still be mounted on the bottom or be moved to the top as some contractor/service images have suggested. I know that mounting the inlet on top is preferable LO wise but would be a PITA from airflow management on a fighter; even if AoA requirements are much less than today's jets.

IIUC, you want the inlets mounted as far back as possible on a supersonic tailless aircraft to accommodate the pitching moments from air mass flow
I think that tends to lead you to top mounted inlets.
 
I see there was an update added to the article & it does look very much like NG’s 6th generation concept.

As an aside I expect the Tempest design to evolve to lose the tails to bring it inline with this kind of NGAD design.

Update 21.30 GMT, Friday, Sept. 18, 2020.

After publishing the first version of this story, we have started receiving suggestions and comments from our readers. One in particular is worth a mention. Anastasis Tsilas noticed the story published by the U.S. Air Force on Instagram. The story has another hint whose shape *might* be hidden also in the 73rd birthday graphic.

The shape in the Instagram story immediately reminded us about the original graphic and a possible shape that appears to be hidden below the main one. Here it is.
 
@ Flyaway
If Tempest lost tails would it not lose its fighters maneuverability, a trade-off with stealth, depends on which you rate rate higher?
 
Air Force 73rd Birthday Graphic Features Rendering Of A Mysterious Next Generation Aircraft
If you look closely, it looks as if there are overlays of several aircraft on the same graphic (one is the obvious delta shape, the other looks sleeker).

73-USAF-poster-detail.jpg

From Flateric post on Facebook, comparison to Rodrigo Avella's FX Concept artwork. 119734571_10223117043776483_2171375486290956553_o.jpg

So the new "Digital Century series" is going to be based on DeviantArt and 3D printing meshes from Turbosquid, presumably.

Some possibilities

-@Rodrigo Avella did the artwork for the USAF poster
- USAF paid some swanky design studio who did pinterest search on "6th gen fighters" and stole @Rodrigo Avella 's artwork.
- @Rodrigo Avella got the contract for the NGAD :)
 
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[...]
- USAF paid some swanky design studio who did pinterest search on "6th gen fighters" and stole @Rodrigo Avella 's artwork.
[...]

Given the cut and paste with regards to the leading edges and wings, the cuts made to make the exhausts rectangular and the fact that someone took the time to hide the serial number that was on Rodrigo's aircraft, that's the most likely hypothesis unfortunately...
 
@ Flyaway
If Tempest lost tails would it not lose its fighters maneuverability, a trade-off with stealth, depends on which you rate rate higher?

Theoretically yes. Strictly my opinion but my impression is that while platform kinematics may still be useful and desirable, WVR "super maneuverability" will be decidedly less so. I believe that increased missile performance, improvements in sensors and vehicle software as well as DEWs will greatly reduced the need for the platform to maneuver; in fact hard maneuvers may be counter productive to survivability in this phase of an engagement. If I'm correct, I'm guessing that having good maneuverability at high altitudes and speeds will be the most desirable trait rather than slowing to a crawl and pointing the nose around in a phone booth.
 
Some possibilities

-@Rodrigo Avella did the artwork for the USAF poster
I guess there's nothing out of usual here (Lockheed hired Syd Mead etc). I have more exciting examples like Russian Andrey Zhirnov (you should know him for his art for many Zvezda moidel kits) making report on hypersonic strike cover for Mitchell Institute...
 
@ Flyaway
If Tempest lost tails would it not lose its fighters maneuverability, a trade-off with stealth, depends on which you rate rate higher?

Theoretically yes. Strictly my opinion but my impression is that while platform kinematics may still be useful and desirable, WVR "super maneuverability" will be decidedly less so. I believe that increased missile performance, improvements in sensors and vehicle software as well as DEWs will greatly reduced the need for the platform to maneuver; in fact hard maneuvers may be counter productive to survivability in this phase of an engagement. If I'm correct, I'm guessing that having good maneuverability at high altitudes and speeds will be the most desirable trait rather than slowing to a crawl and pointing the nose around in a phone booth.

The reason I definitely think the vertical fins will go from the Tempest design is on a fighter that’s a big target for shortwave raider I believe. Plus we know BAe through the Tranis program has been doing a lot of work on fluidic thrust vectoring.
 
@ Flyaway
If Tempest lost tails would it not lose its fighters maneuverability, a trade-off with stealth, depends on which you rate rate higher?

No, it would not lose it's maneuverability. In fact, it would increase it. As with the X-36, they found removing the vertical tails greatly increases roll rate. Which makes sense, since you have lowered roll damping as a result. The whole idea behind the ICE program was to maintain high performance without the vertical tails.
 
Yep. I would expect something like Lockheed's ICE to be the basis for a full scale demonstrator.

IOW the manned component might very well end up looking like a flying masonry trowel. I do wonder if the inlets will still be mounted on the bottom or be moved to the top as some contractor/service images have suggested. I know that mounting the inlet on top is preferable LO wise but would be a PITA from airflow management on a fighter; even if AoA requirements are much less than today's jets.

IIUC, you want the inlets mounted as far back as possible on a supersonic tailless aircraft to accommodate the pitching moments from air mass flow
I think that tends to lead you to top mounted inlets.

Maybe on an aircraft that isn't maneuvering. On a fighter, they usually want them farther forward. One reason is it increases internal volume on small volume limited airframes and, as Northrop found with their VATOL design, an inlet placed far back on the fuselage tends to ingest vortices with any sort of yaw at high alpha, which greatly reduces pressure recovery in the inlets. The greatest problem I see with forward mounted inlets is they increase side area ahead of the CM and also the drag from the duct could add to yaw instability at slight yaw angles, making a tailless control system work that much harder to keep the pointy end facing the right direction.

Having said all of that, both of LM's ICE designs had the inlets ventrally located near the nose. The USAF version had them just set back from the leading edge, I assume for pressure recovery at high alpha. The Navy version having them on the lower side of the fuselage, similar to the X-36, the design from which it was based.
 
The greatest problem I see with forward mounted inlets is they increase side area ahead of the CM and also the drag from the duct could add to yaw instability at slight yaw angles, making a tailless control system work that much harder to keep the pointy end facing the right direction.

You're right; the pitching moment is for non-maneuvering (mainly under acceleration) but the general directionally destabilizing moments
due to mass flow effects are avoided by placing the inlets aft of the c.g.

That's the argument made in "Effective Design of Highly Maneuverable Tailless Aircraft" where a Lockheed Martin fellow goes through a
thought exercise of making the F-22 tailless.
 
Chatted with some of the people who worked on Lockheed's ICE; to their knowledge there's no
full scale flight demonstrator but the USAF academy is flying subscale demonstrators and
some of the technologies explored in ICE have been taken up by other programs.
 
@ Flyaway
If Tempest lost tails would it not lose its fighters maneuverability, a trade-off with stealth, depends on which you rate rate higher?

No, it would not lose it's maneuverability. In fact, it would increase it. As with the X-36, they found removing the vertical tails greatly increases roll rate. Which makes sense, since you have lowered roll damping as a result. The whole idea behind the ICE program was to maintain high performance without the vertical tails.

The other point to remember is that BAE Systems have flown at least two UAVs (Demon and MAGMA) under the FLAVIIR initiative to test fluidic flow control in order to get rid of conventional flaps, and MAGMA also demostrated fluidic thrust-vectoring. Fluidic thrust vectoring in particular has direct applicability to removing the vertical tail.

In general the vertical tail is the most lose-able control surface on a modern aircraft, you can approximate its effects using the other control surfaces (as flying wings routinely do). The main use of the vertical tail inflight is instantaneous pointing of the nose, sustained turns about the yaw axis are done with a combination of pitch and roll, not yaw control. If you can use fluidic flow control or fluidic thrust-vectoring to take over pointing the nose, then there's no reason left to have a vertical tail.
 
The other point to remember is that BAE Systems have flown at least two UAVs (Demon and MAGMA) under the FLAVIIR initiative to test fluidic flow control in order to get rid of conventional flaps, and MAGMA also demostrated fluidic thrust-vectoring. Fluidic thrust vectoring in particular has direct applicability to removing the vertical tail.

MAGMA/Demon didn't make the cut in the NATO AVT-239 effort for a fighter; they went with ICE.

There are a number of issues for fluidic control, particularly in the high AoA regime. It really can't generate a moment quickly
enough to arrest even something like a gust at subsonic speeds; the B-2's high aspect ratio wings have that long moment arm
which lets you get away with yaw control.

IIRC, none of the NATO AVT configurations got much above 20 degrees which doesn't meet the
standard USAF definition for high AoA.
 
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I think he largely misses the point: the NGAD demonstrator was full scale.
And that's for a program with an overlapped AoA. So, to my mind, the NGAD demonstrator is more like JMR-TD
where the Army has been adamant that:

a. it's not a prototyping effort for FVL
b. it's not indicative of final FVL perf reqs
c. it's void where prohibited
 
There are a number of issues for fluidic control, particularly in the high AoA regime.

If you're at high-AOA, your vertical tail is largely masked anyway.

Which was part of the genius of Northrop's YF-23 design. Take a look; its unique tail design prevents it from being masked at high AoA.
 
There are a number of issues for fluidic control, particularly in the high AoA regime.

If you're at high-AOA, your vertical tail is largely masked anyway.
Not true at all. The VTs in the F-22 are doing God's work in coordinating high AoA nose pointing.
The TVC there is mainly preventing pitch up which unloads all of the other control surfaces.
 
Not true at all. The VTs in the F-22 are doing God's work in coordinating high AoA nose pointing.
The TVC there is mainly preventing pitch up which unloads all of the other control surfaces.

The TV also provides pitch trim at supersonic speeds, which creates less drag than having the horizontal tails trimming it.
 

That's a pretty good article by Steve Trimble, sticking to the facts :)

Except: No one called the AFTI efforts full scale demonstrators since they really weren't.
AFTI modded several aircraft into flying testbeds including that F-15B with the automatic
aerial cannon FCS.

And the Dem/Val birds were not competitive prototypes. AFAIK, the Dem/Val birds did not have to have any bearing
whatsoever on the production ATF configuration; the YF-23 certainly didn't but I'm sure it didn't hurt Lockheed
that they tried to make the YF-22 as close as possible to their final EMD proposal.

I tend to think the better analog might be JMR-TD where you have teams build full scale flight demonstrators which are
in some sense, deliberately disconnected from a formal TMRR effort.
 
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As just a "fanboy" I didn't understand this paragraph about retiring the 117:

“It was a bleeding-edge technology that was a unique, game-changing product in the field, which we fielded and operated for a specific amount of time and then moved on to another rapidly emerging technology that we just couldn’t adapt to that exact same platform,” Kelly says.

What other "rapidly emerging technology"?
 

That's a pretty good article by Steve Trimble, sticking to the facts :)

Except: No one called the AFTI efforts full scale demonstrators since they really weren't.
AFTI modded several aircraft into flying testbeds including that F-15B with the automatic
aerial cannon FCS.

Was that one really considered part of the AFTI program though? I thought the F-16 and F-111 were the only AFTI aircraft. :confused:
 
Was that one really considered part of the AFTI program though? I thought the F-16 and F-111 were the only AFTI aircraft. :confused:

Even with its limited application of control configured
vehicle technology, the AFTI/F-15 was highly successful in adding
to the advanced fighter technology base. By changing the control
laws in its control augmentation system, adding an ATLIS-II
electro-optical target tracker pod (78:169), and adding a special
interface unit to tie the flight and fire control systems
together, the AFTI/F-15 achieved a slight control surface
decoupling (96:26; 78:169). The AFTI/F-15 automatically fine-
tuned the fire control cues and decoupled flight control surfaces
(i.e., made them work independently), then limited maneuvers to
plus or minus 1 G during the final seconds of weapons delivery or
gun firing (96:26). This arrangement allowed air-to-air gunnery,
strafing, and bombing from unusual flight profiles (78:170). In
August 1982 the AFTI/F-15 completely destroyed with a two second
burst a maneuvering PQM-102 drone in a most difficult gun firing
condition (78:169-170; 96:26). (The PQM-102 was flying at 420
knots, in a 4 G right turn into its attacker, while the AFTI/F-15
was in a 3.3 G right turn at 400 knots, for a 130 degree aspect
attack at 1.7 kilometers (78:169).)

https://ia800109.us.archive.org/35/items/DTIC_ADA166724/DTIC_ADA166724.pdf
 
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AF CoS on NGAD:

NGAD: Breaking Records
Air Force acquisition chief Will Roper revealed at AFA’s virtual Air, Space & Cyber conference last week that the service has already flown a Next Generation Air Dominancedemonstrator aircraft, and it has broken “lots of records.” Asked to clarify if those records are in the area of program speed or physical performance, Brown said he would not “talk about that aspect.”

However, “I’ll just tell you that we’re able to do things differently and a bit faster than we have in the past,” he said. The NGAD program is “less about what we build, it’s how we build it,” and the goal is to “get it into the hands of the warfighter much faster, and this is a way that we can do that.”

Asked if he thinks the Air Force can afford Roper’s approach to buying new aircraft, which requires flipping the majority of spending from sustainment to design and procurement, Brown said yes, but USAF will have to change its business model to make it work.

“You want the cost of ownership to be roughly the same, but change the flow of that money, so maybe more up front,” Brown said. Using the Roper model will “accelerate change,” Brown said, by making the systems the Air Force does field more adaptive and more abreast of rapidly-changing technology. “It’s a different thought process,” he said.

“I want to … make sure we work industry,” he said, acknowledging that companies “have shareholders they have to worry about,” while Brown has to satisfy national security needs. The Air Force must “do this better so [industry has] a business model that’s sustainable.”
 
Ah yes the nub of the argument. The companies aren't making enough goodies to keep shareholders happy. An air force that buys a new fighter every 3 years is much more lucrative than one that buys a new fighter every 20 years. Is the MIC there to serve the armed forces or vice versa?

Trouble is what if it doesn't work out cheaper? There is a difference between knocking up a demonstrator and building a production ready aircraft. Prototypes historically never took long to build, neither did Y-series aircraft. But the trials and certification and training will still take time before you reach IOC. Roper is talking about rapid fleet changes, you might only just be getting the bugs ironed out of the F-37A before your churning out the F-38 and starting all over from scratch. Will constant churn be a good thing for the USAF? And to be fair it seems Congress has far more clout than the service itself about what types it ultimately operates and hangs on to.
 

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