estorilm
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Re: USAF Considering New Build F-15X

Tue Aug 07, 2018 3:30 pm

smithbs wrote:
LightningZ71 wrote:
Checksixx, flying combat missions over hostile airspace with a real SAM threat is FAR AND AWAY different from the air sovereignty missions being flown from Alaska and Hawaii that continue to consume flight hours on a limited number of available frames. I'm glad that the F-22 was available for Syria, where its features could be put to proper use. However, over northern Iraq, Afghanistan, and other areas of low intensity conflict with no real SAM presence or even the presence of an A2A threat, using the F-22 is an absolute waste. THAT is the point I was trying to make.


It may be a different use but airspace policing is still part of the F-22 mission. You can't just park them for the day when their unique abilities become qualified. As per USAF training and doctrine they are going to fly an allocated number of hours each year - at minimum for training and readiness, and around a couple hundred hours per year. In the USAF bureaucracy, you never say a squadron is without a mission unless you want it gone. A squadron without a day-in-day-out mission will get the budget axe and the birds will go to a squadron that does have a mission.

Are F-35's going to be deployed to Alaska to run the same sort of patrol missions the F-22's do up there, escorting the TU-95s and such? Seems like a perfect use of the F-35 and a dramatic reduction in unnecessary flight hours for the F-22 (I mean the Russians have already seen the F-22 up close many times by now, and they know what they're capable of).
 
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Tugger
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Re: USAF Considering New Build F-15X

Tue Aug 07, 2018 5:30 pm

ThePointblank wrote:
Not to mention that third party suppliers that fed the F-22 production have probably stopped producing their components, or are totally out of business altogether.

This is a very real and constant and expensive problem for many modern military programs. Systems are built, tested, rebuilt and tested again and certified, and locked into to production.... then the chip or component goes out of production. So you have to do a mass buy or redesign or...? Military programs, like the F-35 in particular but it also goes for the F15 etc., spans so many decades that it is impossible to use the same components the entire time. This means the systems need to be reworked and recertified every five or so years (average span of most electronic components) to allow interchangeability and compatibility with that is and has been flying and the parts that are in the field. It is really annoying for Buyers and Engineers and Programs.

Tugg
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ThePointblank
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Re: USAF Considering New Build F-15X

Tue Aug 07, 2018 11:05 pm

Tugger wrote:
ThePointblank wrote:
Not to mention that third party suppliers that fed the F-22 production have probably stopped producing their components, or are totally out of business altogether.

This is a very real and constant and expensive problem for many modern military programs. Systems are built, tested, rebuilt and tested again and certified, and locked into to production.... then the chip or component goes out of production. So you have to do a mass buy or redesign or...? Military programs, like the F-35 in particular but it also goes for the F15 etc., spans so many decades that it is impossible to use the same components the entire time. This means the systems need to be reworked and recertified every five or so years (average span of most electronic components) to allow interchangeability and compatibility with that is and has been flying and the parts that are in the field. It is really annoying for Buyers and Engineers and Programs.

Tugg

Yeah, the problem is known as Diminishing manufacturing sources and material shortages (DMSMS). Well known and understood problem, just takes time, money and effort to effectively mitigate the problem.
 
Ozair
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Re: USAF Considering New Build F-15X

Wed Aug 08, 2018 2:45 am

estorilm wrote:
Are F-35's going to be deployed to Alaska to run the same sort of patrol missions the F-22's do up there, escorting the TU-95s and such? Seems like a perfect use of the F-35 and a dramatic reduction in unnecessary flight hours for the F-22 (I mean the Russians have already seen the F-22 up close many times by now, and they know what they're capable of).

F-35s are going to Alaska, currently planned two squadrons, but to Eielson AFB, not Elmendorf AFB where the F-22s are located. No reason they couldn’t forward deploy to Elmendorf if the requirement existed, or deploy from Eielson but the bases are approximately 300 miles apart and depending upon where the airspace incursions happen may dictate which bases responds.

I’d expect, based on the GAO report linked on the previous page, that there will be some harmonization of F-22 basing. Perhaps Hawaii will lose their jets, convert the Guard unit to F-35 or back again to F-15C?, and they will be rolled to Elmendorf to create a larger critical mass. Given the frequency of Red/Green Flags now being run in Alaska concentrating there makes a bit more sense.
 
estorilm
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Re: USAF Considering New Build F-15X

Wed Aug 08, 2018 2:30 pm

Ozair wrote:
estorilm wrote:
Are F-35's going to be deployed to Alaska to run the same sort of patrol missions the F-22's do up there, escorting the TU-95s and such? Seems like a perfect use of the F-35 and a dramatic reduction in unnecessary flight hours for the F-22 (I mean the Russians have already seen the F-22 up close many times by now, and they know what they're capable of).

F-35s are going to Alaska, currently planned two squadrons, but to Eielson AFB, not Elmendorf AFB where the F-22s are located. No reason they couldn’t forward deploy to Elmendorf if the requirement existed, or deploy from Eielson but the bases are approximately 300 miles apart and depending upon where the airspace incursions happen may dictate which bases responds.

I’d expect, based on the GAO report linked on the previous page, that there will be some harmonization of F-22 basing. Perhaps Hawaii will lose their jets, convert the Guard unit to F-35 or back again to F-15C?, and they will be rolled to Elmendorf to create a larger critical mass. Given the frequency of Red/Green Flags now being run in Alaska concentrating there makes a bit more sense.

Interesting - thanks! Seems like a perfect real-world use of the F-35 for domestic ops, if anything it would be great PR for the program to get some shots of the "doomed" JSF in active duty escorting Russian bomber.

I don't entirely agree with the reports of excessive F-22 hours, but I really hope they start supplementing their current tasks with more JSF aircraft and giving them a bit of a break for stuff like this.

edit: I suppose domestically, this would also be a perfect use of any sort of F-15X, as it's really a purely air-to-air role, however I still think it's an even better use of our current older non-E/F models. This whole F-15X thing is a joke. :)
 
texl1649
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Re: USAF Considering New Build F-15X

Wed Aug 08, 2018 3:21 pm

I do continue to think the USAF is exploring what options make sense. I think the silver bullet fleet has to be prioritized for longevity, and as per above/elsewhere comments I don't think missions intercepting TU-95's etc. make sense for the F-22, or pilot hours. Maintenance, deployments, etc. like this seem like a waste of a great, but highly limited resource.

Hawaii/Alaska in general are silly places for stealth fighters, which I've never really understood, unless a stepping off point for Korea etc. Regardless, and some of the comments here seem too impassioned for my preference to reply, there does seem to be more reporting/consideration of the concept.

The F-35 may certainly wind up being a great $135MM bomb sled in high threat environments, but it will never be a great interceptor. And flying over the water up near Alaska, I'll always prefer our guys have two engines. Just my two cents on the internet.

https://www.airforcetimes.com/news/your ... cd-eagles/
 
RJMAZ
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Re: USAF Considering New Build F-15X

Wed Aug 08, 2018 11:21 pm

texl1649 wrote:
The F-35 may certainly wind up being a great $135MM bomb sled in high threat environments, but it will never be a great interceptor.

You clearly dont know what makes a good interceptor.

The F-35 can fly faster for longer than any western aircraft besides the F-22. It is the perfect interceptor.

The F-35 can sit on Mach 1.6 for nearly 50% longer than the Eurofighter, Rafale or F-15C.

Eurofighter: 11T empty 18T thrust 5T fuel
Rafale: 10T empty 15T thrust 4.7T fuel
F-15C: 12.7T empty 21T thrust 6.1T fuel
F-35: 13.1T empty 18T thrust 8.4T fuel

Now it doesnt take a rocket scientist to realise at max afterburner the F-35 will fly for longer. Add external fuel tanks to the other aircraft and they wont be flying mach 1.6.
 
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Slug71
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 12:07 am

RJMAZ wrote:
texl1649 wrote:
The F-35 may certainly wind up being a great $135MM bomb sled in high threat environments, but it will never be a great interceptor.

You clearly dont know what makes a good interceptor.

The F-35 can fly faster for longer than any western aircraft besides the F-22. It is the perfect interceptor.

The F-35 can sit on Mach 1.6 for nearly 50% longer than the Eurofighter, Rafale or F-15C.

Eurofighter: 11T empty 18T thrust 5T fuel
Rafale: 10T empty 15T thrust 4.7T fuel
F-15C: 12.7T empty 21T thrust 6.1T fuel
F-35: 13.1T empty 18T thrust 8.4T fuel

Now it doesnt take a rocket scientist to realise at max afterburner the F-35 will fly for longer. Add external fuel tanks to the other aircraft and they wont be flying mach 1.6.


Not to mention the F-35 will ALWAYS have a lower RCS than the F-15C. And it has the network/communication advantage.
It can also carry enough weaponry internally for most A2A engagements.
 
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 3:57 am

To help it explain this further take two hypothetical aircraft.

Aircraft A can supercruise at mach 1.6 and burns 5t of fuel per hour at that speed.

Aircraft B has a lower thrust to weight and needs afterburner to sustain mach 1.6. It burns 10t of fuel per hour while traveling at mach 1.6.

Now if aircraft B had twice the internal fuel capacity it can effectively fly just as fast and as far as the supercruising aircraft.

Fuel effectively determines which aircraft is faster.

When it comes to maximum range at subsonic speed aircraft B would probably travel further than aircraft A. The lower thrust to weight fighters engine would be at peak efficiency versus the supercruising aircraft would have the engines at a very low thrust setting. So aircraft B would probably be the better aircraft to choose.

The F-35 is more like aircraft B, the F-22 more like aircraft A. We shouldnt get caught up on maximum speeds. Fuel is life.

The F-22 has a much smaller fuel capacity relative to its empty weight (fuel fraction) when compared to the F-35. The F-35 has slightly more internal fuel than the F-22 even though the F-22 weighs 50% more empty! The F-22 is very underfueled by comparison yet we consider the F-22 the benchmark of kinematic performance.

Lets take a basic air to air mission profile and compare the F-35 to the benchmark F-22. Both aircraft take off and fly 600nm at subsonic speed to the combat zone. At this point the F-35 is at 70% fuel capacity, the F-22 is at 60% fuel capacity. The F-22 burns 33% more fuel as it weighs 50% more while empty.

To return back to base both aircraft will require roughly the same percentage. This means the F-35 has 40% of its fuel capacity to use in the combat zone while the F-22 has only 20% of its fuel to use.

The 40 vs 20 means the F-35 now has twice the fuel to burn. It can use afterburner to easily keep up with the supercruising F-22. The F-35 can launch AMRAAM's high and fast just like the F-22 as it has excess fuel to use afterburner. So its performance disadvantage isnt as clean cut as some suggest.

It is worth noting that fuel is Suhkois biggest advantage allowing it to have F-22 like speed during engagements. In the above mission profile it would have nearly 50% of its internal fuel still available in the combat zone.
 
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seahawk
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 6:34 am

The problem is that the fuel burn in afterburner is more than double than the fuel burn at mil power - we are talking about 5-10 times (F-16 is around 8 times for example).

So even if you start with double the fuel, you still burn it 5-10 times faster.
 
RJMAZ
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 10:07 am

Thats not true at all. It is just over double the consumption per pound of thrust.

The F404 for example is:

Specific fuel consumption:
Military thrust: 0.81 lb/(lbf·h) (82.6 kg/(kN·h))
Full afterburner: 1.74 lb/(lbf·h) (177.5 kg/(kN·h))

If we assume those consumption figures are similar for both the F119 and F135 we can calculate the fuel burn of both F-22 engines at 100% military thrust versus the F-35 at full afterburner.

F-35 has 43,000lb of thrust at 1.74lb = 74,800lb of fuel per hour.

F-22 has 52,000lb of thrust at 0.81lb = 42,000lb of fuel per hour.

So the F-35 burns 75% more fuel in full afterburner than the F-22 does with both engines in military power.

So if the F-22 had 20% of its fuel to use in a sprint against the F-35's 40% fuel the F-35 will fly faster and further.

We should also take into account thrust to weight ratios.

The F-35 at full afterburner and 50% fuel has a thrust to weight ratio of 1.14. The F-22 at full military thrust has a thrust to weight ratio of only 0.97.

The F-35 will not need full afterburner to sustain mach 1.6 once it gets there. At two thirds afterburner setting and around 38,000lb of thrust the F-35 would have a thrust to weight ratio of 1.0. This would mean the fuel burn only 55% higher than the F-22 while cruising at mach 1.6.

So on any mission profile with a subsonic transit over bout 400nm radius the F-35 will be able to exceed the speed of the F-22 by simply using afterburner.

The F-22 is a niche aircraft and will consume lots of fuel from aerial refueling assets. Thats why the F-22 production was cancelled so fast as it has too many weaknesses.
 
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seahawk
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 11:35 am

Why should the Raptor need fuel dry thrust to achieve the same speed? It would have to be very draggy to need 20% more thrust than the F-35 to keep flying at a fixed speed.

Some sources claim the specific fuel consumption to be:

F100-PW-229
(MIL) 17,800lbs @ 0.726 lb/Hr/lb st
(MAX) 29,100lbs @ 2.060 lb/Hr/lb st

F110-GE-129
(MIL) 17,000lbs @ 0.745 lb/Hr/lb st
(MAX) 29,000lbs @ 1.900 lb/Hr/lb st

F414-GE-400
(MIL) 14,700lbs @ 0.840 lb/HR/lb st
(MAX) 22,000lbs @ 1.850 lb/HR/lb st

F119-PW-100
(MIL) 25,000lbs @ (~0.800?) lb/HR/lb st (Speculation varies between 0.600 - 0.860...)
(MAX) 37,000lbs @ (~1.950?) lb/HR/lb st

F135-PW-100
(MIL) 28,000lbs @ 0.886 lb/HR/lb st (a bit high)
(MAX) 43,000lbs @ (~1.950?) lb/HR/lb st
 
RJMAZ
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 12:46 pm

seahawk wrote:
Why should the Raptor need fuel dry thrust to achieve the same speed? It would have to be very draggy to need 20% more thrust than the F-35 to keep flying at a fixed speed.

The F-22 weighs 50% more empty than the F-35. The F-22 is also much larger with 35% greater wetted area. So the F-22 would need atleast 25% more thrust to maintain the same speed. That would be fairly conservative.


seahawk wrote:
Some sources claim the specific fuel consumption to be:

F100-PW-229
(MIL) 17,800lbs @ 0.726 lb/Hr/lb st
(MAX) 29,100lbs @ 2.060 lb/Hr/lb st

F110-GE-129
(MIL) 17,000lbs @ 0.745 lb/Hr/lb st
(MAX) 29,000lbs @ 1.900 lb/Hr/lb st

F414-GE-400
(MIL) 14,700lbs @ 0.840 lb/HR/lb st
(MAX) 22,000lbs @ 1.850 lb/HR/lb st

F119-PW-100
(MIL) 25,000lbs @ (~0.800?) lb/HR/lb st (Speculation varies between 0.600 - 0.860...)
(MAX) 37,000lbs @ (~1.950?) lb/HR/lb st

F135-PW-100
(MIL) 28,000lbs @ 0.886 lb/HR/lb st (a bit high)
(MAX) 43,000lbs @ (~1.950?) lb/HR/lb st

These all prove my argument. They are all between 2-3 times the fuel burn per pound of thrust when in afterburner. As the F-35 would have double the available fuel once at 600nm it should be able to match the F-22 easily.

Regarding engine SFC there are some common trends. The higher the bypass ratio the more fuel efficient the engine is at dry thrust. But the engine efficiency becomes much worse when in full afterburner.

The F101 for instance has a bypass ratio of 2:1 with lots of byass air. It has an excellent dry thrust SFC of 0.562 but an afterburner SFC of 2.46. Another attribute is all that bypass air can be burnt in the afterburner allowing it to have a massive 70% thrust increase when in afterburner.

A low byass turbofan or leaky turbojet will have a worse dry thrust SFC but a better afterburning SFC. It will also have a smaller gain from afterburner with around a 50% increase due to there being less bypass oxygen to burn.

The F119 and F135 have lower bypass ratios than the F110 and F100. So the F404 fuel burn figures I provided would be the most accurate.

It is also worth noting that afterburning SFC increases the closer you get to maximum thrust. So the F-35 at two thirds afterburner or 38,000lb of thrust would probably have a SFC of below 1.5. This makes the F-35 look even better.

Fighters these days still spend 90+% of the time at subsonic speeds as there will always be less drag at subsonic speeds. So for optimum range and speed the best option is actually an aircraft with lower thrust to weight aratio. You want a engine with good fuel burn when that runs near peak efficinecy at high subsonic speeds and then use afterburner when you want to go supersonic.

Another hypothetical aircraft design. If you took the F-22 plugged up one intake, removed one engine and filled the space with 4000kg of extra fuel you would end up with a better overall fighter. Now it could no longer supercruise but that single engine at full dry thrust would cruise nicely at mach 0.9 with pek efficiency. It would fly atleast 50% further than a normal F-22 due to a 50% increase in fuel capacity. In full afterburner it would probaby be able to to sustain the original F-22's supercruise speed but burn twice the fuel doing so. As long as the aircraft spends less than a third of the flight supersonic then the single engine version would be better off.

This is why the F-35 being slightly underpowered on paper when fully loaded isnt a problem. It has more than enough dry thrust to cruise at mach 0.9 and enough wet thrust to sustain mach 1.6.
 
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seahawk
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 1:03 pm

Just with the problem that weight does play no direct part for a straight and level flight at constant speed, as the wing loading is the relevant factor together with drag, with is also influenced by the size but also by the angle of attack needed by the aircraft. And the wing loading of the F-35 is much higher than that of the F-22.

https://nptel.ac.in/courses/101104007/Module2/Lec5.pdf
 
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trpmb6
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 1:08 pm

A few questions;

Do you have a source for the empty weight of the F-22 vs F-35. I don't buy into the 50% number.
What is each aircraft's fuel payload capability (internal).
How long can the F-35 frame hold a sustained afterburn? Most aircraft in our fleet can't sustain an afterburn for very long which drastically changes the math here.

Couldn't it be argued that the F-22's ability to supercruise allows it to engage faster? That could be important when you are scrambling to intercept if you aren't already loitering.
 
estorilm
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 1:43 pm

trpmb6 wrote:
A few questions;

Do you have a source for the empty weight of the F-22 vs F-35. I don't buy into the 50% number.
What is each aircraft's fuel payload capability (internal).
How long can the F-35 frame hold a sustained afterburn? Most aircraft in our fleet can't sustain an afterburn for very long which drastically changes the math here.

Couldn't it be argued that the F-22's ability to supercruise allows it to engage faster? That could be important when you are scrambling to intercept if you aren't already loitering.

Maybe I'm just not good at following math (ahem, RJMAZ lol) - but I'd tend to agree in that I'd assume the F-22 would be able to intercept using less fuel (1.5 supercruise for example) than an F-35 at the same speed for the same distance. I guess your point is that even so, the F-35 arrives on-station with more fuel remaining. To me that's kinda a wash though, loiter time isn't much of an issue for the Raptor compared to the Lightning which is more of a strike platform.

This might be a stupid question, but can the F-22 supercruise with the drop tanks? I guess it wouldn't really need to - if they were called on for an intercept they'd drop them immediately anyways (but then again, they'd probably have near full fuel internally).

I guess the biggest take-away from all of this is that these numbers are worlds different than any sort of F-15 variant. I didn't realize that the F-22 is the ONLY fighter at Elmendorf. Not much chance of F-15's going back there I guess, but not unreasonable to imagine a few F35's heading over.
Last edited by estorilm on Thu Aug 09, 2018 1:59 pm, edited 1 time in total.
 
RJMAZ
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 1:45 pm

seahawk wrote:
Just with the problem that weight does play no direct part for a straight and level flight at constant speed, as the wing loading is the relevant factor together with drag, with is also influenced by the size but also by the angle of attack needed by the aircraft. And the wing loading of the F-35 is much higher than that of the F-22.

https://nptel.ac.in/courses/101104007/Module2/Lec5.pdf

I have taken that into account.

The F-22 weighs 50% more empty it should burn 50% more with everything being equal.

The F-22 has 35% more wetted area with everything else being equal it should burn 35% more fuel.

I was extremely conservative by assuming the F-22 burns only 25% more fuel.

The F-35 is the first fighter aircraft to have significant body lift. So wing loading isnt a good way to determine lift to drag
 
RJMAZ
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 2:07 pm

trpmb6 wrote:
A few questions;

Do you have a source for the empty weight of the F-22 vs F-35. I don't buy into the 50% number.
What is each aircraft's fuel payload capability (internal).

All the specs are public.
F-22 weighs 19,700kg empty 8,200kg of internal fuel
F-35 weighs 13,154kg empty 8,382kg of internal fuel
So the F-22 weighs exactly 50% more with less internal fuel.

https://en.m.wikipedia.org/wiki/Fuel_fraction

"fuel fractions of 29 percent and below typically yield subcruisers; 33 percent provides a quasi–supercruiser; and 35 percent and above are needed for useful supercruising missions. The U.S. F-22 Raptor’s fuel fraction is 29 percent"

The F-35 has a fuel fraction of a massive 39%.


trpmb6 wrote:
How long can the F-35 frame hold a sustained afterburn? Most aircraft in our fleet can't sustain an afterburn for very long which drastically changes the math here.
At a 600nm radius there is only enough fuel for both aircraft to go supersonic for around 10 minutes. The F-22 standard mission profile has a 100nm supercruise which is only 6 minutes. So heating wont be an issue in real combat situations.


trpmb6 wrote:
Couldn't it be argued that the F-22's ability to supercruise allows it to engage faster? That could be important when you are scrambling to intercept if you aren't already loitering.
You can always make up an unrealistic situation to make the F-22 look superior. For example you have to zoom climb to 70,000ft to intercept an inbound Mig-31 and you only have two minutes from wheels up to get into a firing position. The F-35 would get there 30 seconds after the F-22.

One thing though, mach 1.6 supercruising is the same speed as mach 1.6 afterburning.

95+% of the F-22's mission profiles the F-35 could sit on the wing of the F-22 the whole way. It would just use afterburners on the supercruise segments.
 
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seahawk
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 2:29 pm

RJMAZ wrote:
seahawk wrote:
Just with the problem that weight does play no direct part for a straight and level flight at constant speed, as the wing loading is the relevant factor together with drag, with is also influenced by the size but also by the angle of attack needed by the aircraft. And the wing loading of the F-35 is much higher than that of the F-22.

https://nptel.ac.in/courses/101104007/Module2/Lec5.pdf

I have taken that into account.

The F-22 weighs 50% more empty it should burn 50% more with everything being equal.

The F-22 has 35% more wetted area with everything else being equal it should burn 35% more fuel.

I was extremely conservative by assuming the F-22 burns only 25% more fuel.

The F-35 is the first fighter aircraft to have significant body lift. So wing loading isnt a good way to determine lift to drag


However at supersonic speeds the wave drag is the dominant factor and the wetted area (aka surface drag) is only a small part of it.

https://nptel.ac.in/courses/101106041/C ... 2-2011.pdf
 
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trpmb6
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 2:38 pm

Thanks for all that info.

What about their specific payloads? Can the F-35 carry the same A2A armaments that the F-22 would be carrying? Without sacrificing stealth capabilities that is. I think we've already addressed that we can hang things on both aircraft's wings to match (somewhat match) the F-15's capability - but that's at a cost to both speed and stealth.

It was always my understanding that the F-35's bay is more designed for A2G armaments and not A2A.
 
RJMAZ
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 3:38 pm

seahawk wrote:
However at supersonic speeds the wave drag is the dominant factor and the wetted area (aka surface drag) is only a small part of it.

https://nptel.ac.in/courses/101106041/C ... 2-2011.pdf

I am well aware of wave drag. It is mainly an issue for transonic not at mach 1.6.

That is why I have reduced the fuel burn from 50% to 25% in my original post. It take all forms of drag into account. If I took into account only wetted area it would burn 35% more. If I took into account weight the F-22 would burn 50% more. I took all aspects into account which is why it burns only 25% more. This is actually extremely conservative.

Do you honestly think the F-22 has some kind of aerodynamic magic where it requires less thrust despite being significantly larger and heavier? The F-35 is a decade newer they arent going to go backwards. Its not like we are talking about extreme speeds where inlet design might restrict top speed.

The wing loading isnt even that bad.

F-35 13,154kg 42.7m2 = 308
F-22 19,700kg 78m2 = 253

Only 20% better and the F-35 has body lift designed into the shape where as the F-22 is a slab with wings. There wouldn't be much difference in lift to drag between the two. Sweep angle of the F-35 wouldnt be an issue at mach 1.6 either.



trpmb6 wrote:
Thanks for all that info.

What about their specific payloads? Can the F-35 carry the same A2A armaments that the F-22 would be carrying? Without sacrificing stealth capabilities that is. I think we've already addressed that we can hang things on both aircraft's wings to match (somewhat match) the F-15's capability - but that's at a cost to both speed and stealth.

It was always my understanding that the F-35's bay is more designed for A2G armaments and not A2A.

The F-35 and F-22 both have nearly identical total internal volume of its weapon bays. The F-35 still has a bit of development left and will carry six missiles. Rumour is there is a new missile in development which explains why the six missile configuration keeps getting pushed as there is no point designing it for the amraam.

In air to air mode
F-35 - six amraams
F-22 - six amraams + two sidewinders
The latest amraam can now hit very short range targets.

In air to ground mode
F-35 - two 2,000lb bombs + two amraams
F-22 - two 1,000lb bombs + two amraam + 2 sidewinders.
Last edited by RJMAZ on Thu Aug 09, 2018 3:51 pm, edited 2 times in total.
 
tjh8402
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 3:40 pm

trpmb6 wrote:
Thanks for all that info.

What about their specific payloads? Can the F-35 carry the same A2A armaments that the F-22 would be carrying? Without sacrificing stealth capabilities that is. I think we've already addressed that we can hang things on both aircraft's wings to match (somewhat match) the F-15's capability - but that's at a cost to both speed and stealth.

It was always my understanding that the F-35's bay is more designed for A2G armaments and not A2A.


As currently configured, the F-35 can only carry 4 A2A missiles internally, either 4xAIM120 or 2xAIM120+2xAIM9. I believe the goal with future blocks is to up that to six internal A2A. I think the F-22 is 6-8 internal. I don’t remember if 2xAIM9 takes up AIM120 stations or if it’s 6xAIM120 + 2xAIM9, but the F22 does carry at least 6xAIM120 internal with possible additional capacity for 2xAIM9.
 
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trpmb6
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 3:48 pm

I was under the impression that the "deepness" of the F-35 made a pure A2A armament more or less impossible. But I suppose they have the abillity to drop away before engaging their motor.

Thanks again.
 
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seahawk
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 3:59 pm

No magic, but different design goals. The F-22 is by design optimized for supersonic speeds, high altitude flying with very little compromise in the design. The F-35 is designed for high subsonic speeds, has to accept the VTOL version and the naval version, all in all it is more of a compromise. I would not be surprised to see the Raptor being very close in efficiency at M 1.6+. In the end there are too many things we do not know, like the AoA of the wing at that speeds or the position of the control surfaces to trim the frame at supersonic speeds. Those can make a lot of difference.

But in the end I think the debate is pointless, as the F-22 is a one trick pony and too expensive to be worth the effort, while the F-35 is the best fighter in the world and truly omnirole, even if it might be a bit worse than the F-22 in super cruise offensive air-to-air missions.
 
tjh8402
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 3:59 pm

trpmb6 wrote:
I was under the impression that the "deepness" of the F-35 made a pure A2A armament more or less impossible. But I suppose they have the abillity to drop away before engaging their motor.

Thanks again.


I can see where it had an impact in that the current block F 35’s can carry a bigger bomb than an F 22 but fewer a lot fewer A2A missiles, but that hardly makes a pure A2A loadout impossible.

If you don’t care as much about stealth, than the F35 carries a lot more missiles, as I don’t think the F22 has provisions to carry nearly as many underwing as the F35, if t can carry any at all (I think I’ve only ever seen F22s with fuel tanks under the wing).
 
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trpmb6
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 5:58 pm

tjh8402 wrote:
If you don’t care as much about stealth, than the F35 carries a lot more missiles, as I don’t think the F22 has provisions to carry nearly as many underwing as the F35, if t can carry any at all (I think I’ve only ever seen F22s with fuel tanks under the wing).


I agree there. F35 has more hardpoints last I checked.

I will say though. If I had the choice of which one to fly. I'd be flying the F22 hands down.
 
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 10:44 pm

seahawk wrote:
No magic, but different design goals. The F-22 is by design optimized for supersonic speeds, high altitude flying with very little compromise in the design. The F-35 is designed for high subsonic speeds, has to accept the VTOL version and the naval version, all in all it is more of a compromise.
That sounds like something off air power australia 10 years ago.

The speed of the F-35 was downplayed or simply not mentioned early in the program to protect the F-22.

The F-35 can supercruise without afterburner at mach 1.2 for 150 miles by using afterburner to accelerate through transonic.

That is actually brilliant considering the thrust to weight ratio of a 100% fueled F-35 with dry thrust is only 0.58. The F-22 is 0.83 by comparison. So the speed difference is much closer if you gave them equal thrust to weight ratios. This further confirms the F-22 has more drag at mach 1.6 as it lines up with the 25% increase value quite nicely.

The whole bit about the F-35 engines not being a supercruising engine is not true. The F-22 engines are nothing special, the F-22 simply has a very high thrust to weight ratio when in dry thrust and a lower drag than 4th fighters at suersonic speeds.
 
DigitalSea
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Re: USAF Considering New Build F-15X

Thu Aug 09, 2018 11:41 pm

Would be a good replacement for the F-35. Let's do it.
 
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Slug71
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 2:00 am

It can sure as hell turn tighter than I've seen an F-15 or F-16 do. The turn at 3:55 is straight up impressive.
Has there ever been an engagement where more than 1 or 2 missiles were needed/fired?

https://youtu.be/vdhGjqSA2ls
 
Planeflyer
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 4:23 am

In a perfect world it would great if the 22 or 35 could carry as much the latest 15’s but consider that with advent of 5g and ev’s Both power and rf devices are going to come down the cost and size scale while becoming much more capable.

Combine this with the proliferation of uav’s And anything that emits or generates a radar return is going to be under persistent attack.

Over the next 20 years entire theaters will be as different from today as a ww1 battlefield was from Waterloo.

The attempt on Maduro is a foreshadowing of the idea that everybody will be on the front line.

The point is spending money on legacy platforms will get us killed.
 
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seahawk
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 4:51 am

RJMAZ wrote:
seahawk wrote:
No magic, but different design goals. The F-22 is by design optimized for supersonic speeds, high altitude flying with very little compromise in the design. The F-35 is designed for high subsonic speeds, has to accept the VTOL version and the naval version, all in all it is more of a compromise.
That sounds like something off air power australia 10 years ago.

The speed of the F-35 was downplayed or simply not mentioned early in the program to protect the F-22.

The F-35 can supercruise without afterburner at mach 1.2 for 150 miles by using afterburner to accelerate through transonic.

That is actually brilliant considering the thrust to weight ratio of a 100% fueled F-35 with dry thrust is only 0.58. The F-22 is 0.83 by comparison. So the speed difference is much closer if you gave them equal thrust to weight ratios. This further confirms the F-22 has more drag at mach 1.6 as it lines up with the 25% increase value quite nicely.

The whole bit about the F-35 engines not being a supercruising engine is not true. The F-22 engines are nothing special, the F-22 simply has a very high thrust to weight ratio when in dry thrust and a lower drag than 4th fighters at suersonic speeds.


Again thrust to weight matters little for constant straight and level flight. And supercruising at Mach 1.2 will logically create less drag than supercruising at Mach 1.6, it is a third slower. So if the the F-22 needs 25% more thrust to fly 30% faster, it is the less draggy airframe.
 
RJMAZ
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 7:44 am

seahawk wrote:
Again thrust to weight matters little for constant straight and level flight. And supercruising at Mach 1.2 will logically create less drag than supercruising at Mach 1.6, it is a third slower. So if the the F-22 needs 25% more thrust to fly 30% faster, it is the less draggy airframe.

Thrust to weight does matter. If the F-22 throttles down to 70% dry thrust we can roughly estimate what supersonic speed and fuel burn it would have. It would be fairly accurate until you hit the transonic region below mach 1.2.

The F-22 has 52,000lb of dry thrust. The F-35 has only 28,000lb of dry thrust. The F-22 has 85% more dry thrust yet manages only 50% additional speed. Based on other drag polars from other aircraft the F-22 clearly has more drag at most speeds.

The F-35 at mach 1.2 would also still be in the tail of the transonic drag peak. So a low afterburner setting giving 10% extra thrust will give a greater speed increase than you would normally expect.

Off topic but if the F-35 received an upgraded engine with a small dry thrust increase it would result in a very big boost in the supercruising speed. Thisnwould give a big boost in range not from an increase in SFC but due to less afterburner required in a typical mission profile.
 
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seahawk
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 7:59 am

But that is the point we do not know. All data points to the Raptor as able to supercruise at M1.8+, but we do not know if it is limited by thrust or by other factors like airframe heating. I personally believe that it is not limited by thrust due to the comparison with the Eurofighter for example.

Furthermore we know that the drag coefficient for supersonic flight peaks at slightly above Mach 1 and is reduced by about factor 3 once you hit Mach 2. So through the higher cursing speed alone the drag of the F-22 is reduced by about 20% (M 1.6 compared to Mach 1.8) - compared to a plane doing Mach 1.2 is is reduced by 50%.

But personally I think the whole focus on supercruise is totally overrated. It is only interesting if you want to give your missiles some extra kinetic energy, but this can be overcome by longer ranged missiles and it is enough if you can accelerate to such speed before missile launch and the F-35 has enough power and the fuel to do just that. So operationally it makes no difference at all, especially as the F-35 will be much more efficient in the subsonic regime.
 
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 2:04 pm

RJMAZ wrote:
In air to air mode
F-35 - six amraams
F-22 - six amraams + two sidewinders
The latest amraam can now hit very short range targets.


So this is why Boeing is pitching the F-15X to supplement the F-35 and F-22:

https://www.popularmechanics.com/milita ... tion-f-15/.

The Advanced Eagle upgrade consists of four so-called "quad pack" hardpoints on the wings, each capable of carrying four AMRAAM missiles for a total of 16.


bt
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trpmb6
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 3:02 pm

bikerthai wrote:

https://www.popularmechanics.com/milita ... tion-f-15/.

The Advanced Eagle upgrade consists of four so-called "quad pack" hardpoints on the wings, each capable of carrying four AMRAAM missiles for a total of 16.


bt


Yeah I think we've gotten a little side tracked with the F-22/F-35 debate when we should really be talking about why the USAF might consider more F-15. That is a role where F-22 and F-35 provide the air-superiority support role to the armament carrying heavy lifter F15. That's what I see this being.

The article linked mentions numbers. If your enemy has more airplanes than you have missiles it won't matter how many of them you shoot down. Granted this isn't exactly a problem seen today.. But it could be some day. Certainly if we let all our aircraft retire without replacements.

Talking with a coworker there's a lot of advantage of having an F-22 sort of acting as a local squadron sensor array where they are the ones doing the seeking and letting the F-15's do the destroying.
 
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 7:03 pm

Although, as a bomb/missile truck, a better platform would be a larger UAV with multiple hard point. But as of now, there is none in existence and none on the drawing board. All the UAV being designed or flown are small and have the same payload limitation as the F-35 or F-22.

And wait, if they have 4 X quad packs, and add to that 4 on the fuselage, that would push the number of missiles to 20.

bt
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RJMAZ
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 10:23 pm

bikerthai wrote:
RJMAZ wrote:
In air to air mode
F-35 - six amraams
F-22 - six amraams + two sidewinders
The latest amraam can now hit very short range targets.


So this is why Boeing is pitching the F-15X to supplement the F-35 and F-22:

https://www.popularmechanics.com/milita ... tion-f-15/.

The Advanced Eagle upgrade consists of four so-called "quad pack" hardpoints on the wings, each capable of carrying four AMRAAM missiles for a total of 16.


bt

That is only internal carraige. The F-35 can carry another four AMRAAM on the wings and two sidewinders on the wing tips. That bring the total to 12 missiles.

The quad pack launcher on the F-15X hadnt been invented yet. The F-35 could easily get a standard dual rail amraam launcher for the wing stations and it would then have 16 missiles.
 
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Slug71
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Re: USAF Considering New Build F-15X

Fri Aug 10, 2018 11:07 pm

trpmb6 wrote:
bikerthai wrote:

https://www.popularmechanics.com/milita ... tion-f-15/.

The Advanced Eagle upgrade consists of four so-called "quad pack" hardpoints on the wings, each capable of carrying four AMRAAM missiles for a total of 16.


bt


The article linked mentions numbers. If your enemy has more airplanes than you have missiles it won't matter how many of them you shoot down. Granted this isn't exactly a problem seen today.. But it could be some day. Certainly if we let all our aircraft retire without replacements.

Talking with a coworker there's a lot of advantage of having an F-22 sort of acting as a local squadron sensor array where they are the ones doing the seeking and letting the F-15's do the destroying.


No country comes close to the number of aircraft the USAF and USN have. It's highly unlikely the US will be out numbered any time soon in any encounter. The F-35 and F-22 also have external hardpoints if more armament is needed. But has there ever been an encounter where any jet has unloaded a full payload (or more than the F-35 and F-22 can carry internally) in an A2A combat engagement? Given that they go up in at least pairs, they should have more than enough armament.

As to the conversation with your co-worker, that's a job better left to AWACS. And why increase cost (and comprise the F-22) by having an F-15 up with the F-22, when the F-22 can better do what the F-15 is proposed to be there for. Doesn't make sense and seems redundant.
 
texl1649
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Re: USAF Considering New Build F-15X

Fri Aug 31, 2018 6:34 pm

It appears Lockheed also sees a need for an alternative to the F-22/F-35 fleet as is planned today. The Super Hornet project (profits) are undoubtedly looked upon with great envy by Lockheed types.

https://www.defenseone.com/business/201 ... ce/150943/

"The new variant — similar to one Lockheed is pitching to Japan — would incorporate the F-35’s more modern mission system and “other advancements in the stealth coatings and things of that nature,” according to a person familiar with the proposal.

“There’s a lot of potential in this idea,” Deptula said. “I’m not sugesting that we jump right into it and embrace it, but from the Japanese perspective when they are looking at and willing to invest in this kind of an alternative as opposed to trying to build an indigenous aircraft that’s not going to get close to what an F-22 can already deliver. It’s a smart move on their behalf.”

A Lockheed spokeswoman declined to comment about the project.

The proposal has echoes of the late-1990s evolution of the F/A-18 Hornet into the Super Hornet. Pitched as a low-risk project, the F/A-18E/F turned out to require a redesign of almost every exterior part. The new wing proved initially troublesome, but the design eventually proved successful."
 
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Re: USAF Considering New Build F-15X

Sat Sep 01, 2018 1:23 am

Slug71 wrote:
It can sure as hell turn tighter than I've seen an F-15 or F-16 do. The turn at 3:55 is straight up impressive.
Has there ever been an engagement where more than 1 or 2 missiles were needed/fired?

https://youtu.be/vdhGjqSA2ls



I watched that several times


The turn was impressive until it
appeared he hit a limiter of some
kind, it’s very noticeable, he pulls
and pulls into a tight turn then
suddenly there’s a noticeable
pitch down

I’m guessing he reached a g limit
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Slug71
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Re: USAF Considering New Build F-15X

Sat Sep 01, 2018 2:13 am

Max Q wrote:
Slug71 wrote:
It can sure as hell turn tighter than I've seen an F-15 or F-16 do. The turn at 3:55 is straight up impressive.
Has there ever been an engagement where more than 1 or 2 missiles were needed/fired?

https://youtu.be/vdhGjqSA2ls



I watched that several times


The turn was impressive until it
appeared he hit a limiter of some
kind, it’s very noticeable, he pulls
and pulls into a tight turn then
suddenly there’s a noticeable
pitch down

I’m guessing he reached a g limit


I wondered about that too. I'd say he pulled a few Gs doing that.
 
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seahawk
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Re: USAF Considering New Build F-15X

Sat Sep 01, 2018 3:01 pm

More like a F-22C version. Mostly the same airframe, just improved engines (probably of the same type though) and new avionics + stealth coatings.
 
bunumuring
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Re: USAF Considering New Build F-15X

Sat Sep 01, 2018 3:24 pm

Hey guys,
I wonder if in the long term Australia might be interested in the hybrid F-22/F-35 Japanese proposal to replace its Super Hornets instead of the F-35?
I know Australia is committed to the F-35 but the decision on what exactly replaces the Super Hornets won't be made for years... And well after the possible Japanese development of the F-22 is launched.
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Dutchy
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Re: USAF Considering New Build F-15X

Sat Sep 01, 2018 5:09 pm

They have 100 F-35's on order. That is more than their inventory of F/A-18A/B's and E/F/G's combined. I doubt they would be interested in additional aircraft in the form of a Japenese F-22 development. Or do you mean instead of some F-35's?
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bunumuring
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Re: USAF Considering New Build F-15X

Sat Sep 01, 2018 10:30 pm

Hey Dutchy,
There are 100 in the requirement overall but only 72 (or is it 74?) actually being budgeted for at this time due to the decision to keep the Super Hornets/Growlers in the RAAF for the medium term, and then to decide what to replace them with : either more F-35s, UAVs, something else or nothing at all.
I am suggesting that MAYBE the F-22 development might be of interest to the RAAF for this last tranche of aircraft to replace the Super Hornets/Growlers...
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ThePointblank
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Re: USAF Considering New Build F-15X

Sun Sep 02, 2018 2:52 am

bunumuring wrote:
Hey Dutchy,
There are 100 in the requirement overall but only 72 (or is it 74?) actually being budgeted for at this time due to the decision to keep the Super Hornets/Growlers in the RAAF for the medium term, and then to decide what to replace them with : either more F-35s, UAVs, something else or nothing at all.
I am suggesting that MAYBE the F-22 development might be of interest to the RAAF for this last tranche of aircraft to replace the Super Hornets/Growlers...
Cheers
Bunumuring

With how expensive F-22's are, and the extremely high likelihood that a Japanese F-22 variant would significantly even more, it's a total non-starter.

Seriously. Look at how much the Japanese paid for their heavily modified copy of the F-16; 3 times the cost of a normal F-16 Block 50, and almost as much as a F-22 costed.

Still interested in buying a Japanese F-22 variant for what is likely going to be a $400 million USD fly-away per aircraft?
 
Ozair
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Re: USAF Considering New Build F-15X

Sun Sep 02, 2018 4:05 am

bunumuring wrote:
Hey Dutchy,
There are 100 in the requirement overall but only 72 (or is it 74?) actually being budgeted for at this time due to the decision to keep the Super Hornets/Growlers in the RAAF for the medium term, and then to decide what to replace them with : either more F-35s, UAVs, something else or nothing at all.
I am suggesting that MAYBE the F-22 development might be of interest to the RAAF for this last tranche of aircraft to replace the Super Hornets/Growlers...
Cheers
Bunumuring

Bunumuring, there would be zero interest in whatever comes out of Japan in the form of an upgraded F-22. The RAAF have stated they will make a decision around 2025 on whether they acquire the last F-35s or keep and upgrade the SH. The Growlers will be around for a long time irrespective of the decision they make on the fighter fleet.

A 3 part article on ASPI the other day talked about this decision and reached some flawed conclusions. Their argument was to upgrade the SH and save some cash but completely ignored the potential for F-35 upgrades in that same period. If the RAAF ordered in for instance 2025 for delivery in 2027 they would likely have access to Blk 5 F-35s, which will have an upgraded engine offering an additional 30% range, better sensors and overall increased capability. Acquiring a Japanese frakenised F-22, or a UK tempest 5 years later, would serve little for fleet commonality and come at a very expensive acquisition and sustainment cost. Those are out of reach for a RAAF that is already building a harmonized force that will likely dominate information warfare within the region for many years to come.
 
Ozair
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Re: USAF Considering New Build F-15X

Thu Sep 13, 2018 5:45 am

I think we can confidently put to bed the rumour that the USAF is interested in the F-15X. As the article suggests a hybrid F-22/35 may be something for the future, within the context of PCA or NGAD, but certainly no funding priority today.

Air Force not considering new F-15 or hybrid F-22/F-35, top civilian says

The two biggest manufacturers of military aircraft have been busy marketing new versions of their fighter jets to the U.S. Air Force, but the service’s top official told Defense News in an exclusive interview that it’s not actually interested in purchasing either of them at the current moment.

This summer, Defense One broke two major stories about sales pitches from Boeing, which is proposing an advanced version of the F-15 to the Air Force, and Lockheed Martin, which has been pushing a hybrid version of the F-22 Raptor and F-35 joint strike fighter similar to what it is reportedly offering Japan.

But just because those companies are offering new jets, doesn’t mean that the Air Force wants them.
In an exclusive Sept. 5 interview, Air Force Secretary Heather Wilson said she believes the service needs to expend its precious financial resources on stealthy, fifth-generation platforms — specifically the F-35 — and thus buying even an advanced fourth generation fighter like the so-called F-15X is not in the cards.

"We are currently 80 percent fourth-gen aircraft and 20 percent fifth generation aircraft,” she said. "In any of the fights that we have been asked to plan for, more fifth gen aircraft make a huge difference, and we think that getting to 50-50 means not buying new fourth gen aircraft, it means continuing to increase the fifth generation.”

What about a new fifth generation plane that would combine the F-35 and F-22?
Wilson shut down that idea as well, saying that proposal "is not something we’re currently considering.”

In a statement, a Lockheed spokesman said that the company was focused on the F-35 program but also looking into generational leaps in capability “to ensure our technology, including existing aircraft, remains a step ahead of advancing threats.”
Boeing declined to comment on this story.

The Air Force secretary’s proclamations seem to pour cold water on both Lockheed and Boeing’s sales pitches, but it is always possible that others inside the service are in favor of buying the F-15X and F-22/F-35 hybrid — and that they could continue making the case to Air Force leadership, potentially winning them over.

Sources that spoke to The War Zone said Boeing was in “very serious” talks with the Air Force over the F-15X, but that the service had shied away from making its interest public so as to not to derail it’s number-one procurement priority, the F-35. Defense News has also heard from multiple sources that the Air Force has been in talks with Boeing over the F-15X for over a year, though it’s unknown at what levels those conversations currently reside.

Experts who spoke with Defense News said it’s very likely that the Air Force intends to keep its focus on ramping up F-35 production for the time being, but that alternative platforms could very well be considered in future years.

However, it is the F-22/F-35 hybrid, not the F-15X, that they believe stands a better chance of being adopted by the Air Force.
Defense One, which broke the story about Lockheed’s hybrid offer, wrote that the proposed jet would involve taking the F-22 airframe and outfitting it with some of the F-35’s more advanced mission systems, though some structural changes could also be involved.
“Every F-22 hybrid or derivative I’ve seen has been great,” said Rebecca Grant, a defense analyst with IRIS independent Research.
The Air Force is in great need of such a stealthy air superiority aircraft because it only procured 183 F-22s, she said. Its other plane that specializes in the air-to-air fight, the F-15C/D, was originally fielded in the 1970s.

Grant said she interprets Wilson’s dismissal of the F-22/F-35 hybrid as a reflection of near-term requirements and priorities, noting that “job one is acquiring the F-35.” But in the future, that jet could be what the service decides it needs to contend with current and future threats.

David Deptula, the dean of the Mitchell Institute for Aerospace Power Studies and a retired Air Force lieutenant general, agreed that the service should continue buying F-35s for the time being.

However, the F-22/F-35 hybrid might be a good option for the service in the future, when it begins looking for a next-generation air superiority jet, which the Air Force has variously called Penetrating Counter Air and Next Generation Air Dominance.

“I think as the Air Force looks down the road at the concept of a Penetrating Counter Air and Next Generation Air Dominance — where it’s looking at and researching how we achieve order of magnitude increases in fundamental aviation elements such as aerodynamics, propulsion, low observability, sensor suite and sensor integration — there are a lot of options,” he said.

The War Zone, which has published the most detailed account of Boeing’s proposal, reported that Boeing is willing to sell the F-15X under a fixed price contract and intends to deliver the aircraft at a unit cost that’s “well below” $95 million (for reference, each Lot 10 F-35A costs about that much, but unit costs are expected to decrease to about $89 million in Lot 11).

The new F-15s would include a suite of new capabilities including a APG-82 radar, the Eagle Passive Active Warning Survivability System (EPAWSS) electronic warfare suite, a Legion Pod-mounted infrared search and track system and the ability to carry up to 22 missiles at a time.

But both Grant and Deptula, who are noted advocates of stealth technology, were less effusive about the sales case for the F-15X.
“I don’t see a role for an F-15X,” Grant said, adding that the service needs the stealth and advanced battle management capabilities of an F-22 or F-35.

While the Air Force used fourth-generation fighters to suppress enemy air defense capabilities during Desert Storm, adversaries have made advances to their own integrated air defenses that will make it difficult for a plane like the F-15X to penetrate, even after stealth platforms have kicked down the door, Deptula said.
“A smart adversary is going to be operating those double-digit surface-to-air missile systems throughout the breadth and depth of the theater, and you’re not going to be able to take them all down in the first 24 hours of a conflict,” he said.

https://www.defensenews.com/digital-sho ... lian-says/
 
Ozair
Posts: 3216
Joined: Mon Jan 31, 2005 8:38 am

Re: USAF Considering New Build F-15X

Thu Sep 13, 2018 5:47 am

double post.
 
texl1649
Posts: 744
Joined: Thu Aug 02, 2007 5:38 am

Re: USAF Considering New Build F-15X

Fri Dec 21, 2018 11:56 pm

Supposedly, this is back on, per tweets from Tyler Rogoway and others. USAF seeking 1.2 billion to buy a dozen. Interesting to see if this plays out. Last 2 decades USAF hasn’t had a lot of new types in the inventory (basically F-35).

https://twitter.com/rtiron/status/10762 ... 78817?s=21

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