Boeing F-15EX/QA and related variants

The airflow field at the back end of the F-15 with the closely spaced round nozzles and vertical stabilizers is very turbulent. This resulted in heavy wear and occasional liberation of the external flaps “ turkey feathers “ on the F100-PW-100 engines. The USAF was spending a lot of man hours and $$ maintaining them, and after performance testing showed virtually no drag increase, the decision was made to take them off on the -100 engine.

In the l997 time frame, GE paid for a service evaluation where two F-15E airframes at Nellis AFB had F110-GE-129 engines installed and were flown for approximately 18 months in that configuration. About 6 months in after a significant amount of maintenance on the nozzles, the external flaps were removed from those Service Eval -129 engines.

I don’t know when it occurred, but the USAF also removed the external flaps on the F101 engines on the B-1B, which is another installation with closely spaced round nozzles.

When the F100-PW-229 was developed, the external flaps were redesigned with a composite material construction and a revised mounting. Flight test determined that these external flaps would survive in the F-15 environment. The USAF decided to save the money and -229s for F-15E were delivered without the external flaps

Why have them installed on -129 engines in the F15EX? There are some signature benefits for covering up the hot internal nozzle parts. Has GE improved the design of the -129 external flaps since the 1997 version sufficiently to survive long term at the back end of the F-15? Time will tell.
 
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They probably have - most of the recent exports are powered by F110s (South Korea, Singapore, Saudi Arabia etc.) and they all have external flaps.
 
Does anyone know how many F-15C and D variants does USAF have with the upgraded (v)3 radar, as of today?
bonus question - is the entire D fleet scheduled to be upgraded to said radar?
 
 
Anybody knows why the aircraft re-installs the engine nozzle flaps?

GE-F129 Engine, which doesnt have PW engine's apparent problem with vibration AFAIK.
But, the F-16 use the F100-PW-229 with nozzle flap.
Because the vibration problem is specific to the F-15 Eagle.
Vibration problem? I thought they were just kept removed because the nozzles themselves required a lot of maintenance?
 
Interesting. They have a very small inventory of F-15E analogs (Ra’am?); I was under the impression that they felt the F-16 Sulfas handled the mission more cost effectively.
 
Interesting. They have a very small inventory of F-15E analogs (Ra’am?); I was under the impression that they felt the F-16 Sulfas handled the mission more cost effectively.

Seems that they have a specific deep hard-target penetrator weapon in mind that is probably too heavy for the F-16 and likely only fits on the F-15 centerline hard point.
 
Interesting. They have a very small inventory of F-15E analogs (Ra’am?); I was under the impression that they felt the F-16 Sulfas handled the mission more cost effectively.

Seems that they have a specific deep hard-target penetrator weapon in mind that is probably too heavy for the F-16 and likely only fits on the F-15 centerline hard point.

So Israel becomes the first export customer for the F-15EX Eagle 2 because of the problem of the hard-target penetrator weapon. Any thoughts on other weapons apart from the hard-target penetrator.
 
Interesting. They have a very small inventory of F-15E analogs (Ra’am?); I was under the impression that they felt the F-16 Sulfas handled the mission more cost effectively.

Seems that they have a specific deep hard-target penetrator weapon in mind that is probably too heavy for the F-16 and likely only fits on the F-15 centerline hard point.
(Apparently the wing pylons are rated for 7,000lbs. See video I just posted above, towards the end.)
 
I'm really enjoying Mooch's channel. I found the one comment he made about a friend who's a Raptor driver and how when its only F-22s it's harder for them to hide their emissions but when 4th gens are part of the mix its much easier to hide. A very interesting anecdote on the benefits of 4th-5th gen teaming.
 
Israel F-15EX (known as IA in Israel) to be delivered, at best, in 2028:
There is no timeline yet, but the earliest Israel would likely receive the new jets would be in 2028. Israel is expected to push for faster delivery. Colbert said Boeing was working “as fast as it can” to supply the aircraft to Israel as soon as possible.

 

"A year after Air Force officials said they had decided to cut their planned fleet of F-15EX Eagle IIs from 144 to 80, the service reversed course—partially—and upped its buy in the 2024 budget to fulfill the homeland defense mission and ensure it reached a goal of 72 new fighters per year, top Air Force leaders said March 15." ...
"The additional batch of F-15EXs will give the Air Force 104 total, up from the 80 it detailed in last year’s budget request. The Air Force originally planned to buy 144 F-15EXs, but a final inventory of 104 jets will remain the Air Force’s position—at least for now."
 

"A year after Air Force officials said they had decided to cut their planned fleet of F-15EX Eagle IIs from 144 to 80, the service reversed course—partially—and upped its buy in the 2024 budget to fulfill the homeland defense mission and ensure it reached a goal of 72 new fighters per year, top Air Force leaders said March 15." ...
"The additional batch of F-15EXs will give the Air Force 104 total, up from the 80 it detailed in last year’s budget request. The Air Force originally planned to buy 144 F-15EXs, but a final inventory of 104 jets will remain the Air Force’s position—at least for now."

In the article linked below, The Drive (The War Zone) meanwhile talks about 128 F-15EXs in total, when taking into account the Aviation Week report about 24 more F-15EXs for the FY2025 budget...


"The Air Force is looking to buy 24 more Eagle IIs in the 2024 Fiscal Year, which would bring the total planned fleet size up to 104 aircraft. This is more than the 80-jet fleet the service had said it was looking at last year, but is still less than the at least 144 examples it originally said it would purchase.
Aviation Week's story yesterday said that the Air Force was looking to order another 24 jets in the 2025 Fiscal Year, but that this would be the final Eagle II buy. This would further bump the expected size of the F-15EX fleet up to 128 aircraft, but it's unclear where those additional Eagle IIs might be expected to go."
 
I wonder if any of F-15Es when they are retired would be converted into QF-15E target-drones?
 
I wonder if any of F-15Es when they are retired would be converted into QF-15E target-drones?

Why? What would a QF-15 do that the QF-16 can't?

We've had surplus F-15A/B/C/D at Davis-Montham for years without feeling a need to convert them into drones.

The thinking now is that the QF-16 successor will need at least some stealth to accurately simulate adversary aircraft like the Su-57 or J-20. And will be a drone from the outset.
 
I wonder if any of F-15Es when they are retired would be converted into QF-15E target-drones?

Why? What would a QF-15 do that the QF-16 can't?

We've had surplus F-15A/B/C/D at Davis-Montham for years without feeling a need to convert them into drones.

The thinking now is that the QF-16 successor will need at least some stealth to accurately simulate adversary aircraft like the Su-57 or J-20. And will be a drone from the outset.

If you want to test the lethality of a new warhead against a large twin-engined fighter, you may want a QF-15.
 
Why? What would a QF-15 do that the QF-16 can't?

Why not? If they're available and they'd simulate large two-engined fighter/fighter-bomber targets as a surrogate for, say, the Su-34 or Su-35.

If you want to test the lethality of a new warhead against a large twin-engined fighter, you may want a QF-15.

This!
 
Why? What would a QF-15 do that the QF-16 can't?

Why not? If they're available and they'd simulate large two-engined fighter/fighter-bomber targets as a surrogate for, say, the Su-34 or Su-35.

If you want to test the lethality of a new warhead against a large twin-engined fighter, you may want a QF-15.

This!

The QFs are not primarily intended for warhead lethality testing. You do most of that in more controlled settings like arena tests. I mean, they only even expend the drones after about 300 hours, which means maybe 1 percent of their flights.

The QFs are needed to simulate enemy tactics and flight behavior. Increasingly, that means being able to simulate a reduced signature aircraft. Which is why the future of the targets like this is probably low-RCS drones.

 
I wonder if any of F-15Es when they are retired would be converted into QF-15E target-drones?
The USAF is looking into purpose built targets in the future. At this point it is easier to manufacture a high performance UAV than it is to convert an airframe; I suspect the QF-16s will be the last of their kind. If nothing else, the F-15Cs will be used long before the F-15Es are...and I can't see the F-15Es being representative targets by the time that airframe is that expendable.

Keep in mind nothing goes to target drone unless it is basically so old it can't be spare parts for active aircraft. Unless you are a lot younger than me, we'll die before F-15Es reach that mark, and more likely that kind of real testing will simply be taken over by cheaper UAVs rather than converted aircraft.
 
Lot 2 and beyond will see a slight price increase.

Well it IS Boeing we're talking about.
Actually its more McDonnell Douglas since their management basically took over.
 
Lot 2 and beyond will see a slight price increase.

Well it IS Boeing we're talking about.
Actually its more McDonnell Douglas since their management basically took over.
If Boeing wants to brag about their shiny new F-15EX they can brag about their management too. ;)
 

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