USAF F-15 fleet grounded

[F-15 Eagle]

You have no idea what you are talking about.

The F-15 has never even reached Mach 2 in its combat history let alone Mach 2.5......

The highest speed it reached in combat was Mach 1.6 when it tried to catch some Iran Mig-25's that were doing high speed passes.. Of course they didn't catch the migs and had to go straight to the tanker afterwards.

The F-35 is better than the F-15 in every way. What you are saying is that it cant replace the F-15 because its slower? I can tell you now it wont be slower in fact it will be faster during most missions.

An F-15 carrying no weapons hitting mach 2.5 in a straight line and landing because you have run out of fuel is not useful at all. You are an idiot if you think it serves a purpose in combat.

At dry military thrust the F-35 will travel as quick as the F-15C/E with the same combat load. This is what you should be comparing it too. An F-15 with a dozen SDB's will most likely travel SLOWER than an F-35 with the same bombs carried internally. From what i have seen the F-35 should be able to accelerate to low supersonic speeds quicker than the Eagle as well.

Uh I do know what I am talking about and thanks for calling me an idiot! The F-15 can travel at Mach 2.5 I don't know were you got your info from, and it does serve a purpose in combat and that is to get to and from a combat area quickly and not take all day thats why they have it in the first place. And there are more types of bombs (heavier ones too) than just the SDB to take into consideration. The Mig-25 outran the F-15 is because it is faster than the F-15, Mach 2.83 verse Mach 2.5. The F-15E has a slightly bigger payload than the F-35. Thats why the Air Force is only replacing the F-16, F-18, A-10, and AV-8 and not the F-15E or F-15C. The F-22 will replace some but not all of the F-15C and the FB-22/2018 Bomber will replace the F-15E, the U.S. Air Force knows what they need and don't need. And I was not trying to offend you I was only trying to just point out the facts, no need to take it too seriously.

 

[RubiconNZ]

According to the USAF Library, I quote: Speed: 1,875 mph (Mach 2.5 plus)
http://www.af.mil/factsheets/factsheet.asp?id=101

Of course the Plus could be anything like the plus on a CVN or SSN, we can only speculate on public figures which as we have been told many times are pretty loose.

Its better to do a quick 2 minute Google search than jumping to conclusions.

 

[F-15 Eagle]

According to the USAF Library, I quote: Speed: 1,875 mph (Mach 2.5 plus)
http://www.af.mil/factsheets/factsheet.asp?id=101

Of course the Plus could be anything like the plus on a CVN or SSN, we can only speculate on public figures which as we have been told many times are pretty loose.

Its better to do a quick 2 minute Google search than jumping to conclusions.

Yep now thats pretty fast. They can probably go a 100 miles in just 15 minutes. 1875 mph is almost as fast as a .308 or a 30-06 rifle bullet.

 

[rjmaz1]

Uh I do know what I am talking about and thanks for calling me an idiot! .. And I was not trying to offend you I was only trying to just point out the facts, no need to take it too seriously.

Again you completely misread my post, i think the idiot comment is starting to stick.

You are incorrect if you think the F-15 can travel Mach 2.5 in combat. The F-15 set that speed on a single high speed run with no weapons. It hit Mach 2.5 and then had to stop and land as it had run out of fuel. I already stated this.

The F-15 has never exceeded Mach 2 in combat let alone Mach 2.5.

Again the fastest speed a USAF F-15 has reached in combat was Mach 1.6 and that was chasing MIG-25'S. The mig-25's weren't even travelling Mach 2 either no where near the Mach 2.83 top speed... I'm trying to find the source now.

I've had this same discussion with another member on here about the F-35's scombat speed and he now realises that you NEVER compare the speed of aircraft using top speeds in clean configuration. I will discuss it again in a little more detail now that more information has been released.

It wasn't long ago that the top speed of the F-22 stated Mach 1.8... The F-15 has a considerably higher top speed Yet the F-22 in combat will travel atleast 50% quicker than F-15.

The reason for this lower top speed on the latest aircraft is due to having fixed intakes instead of variable. Fixed intakes are lighter and more stealthy however they have to be tuned to a certain airspeed so that the engines recieve the correct airflow. US studies done 10-15 years ago (which i have seen) have proven that most Mach 2+ aircraft rarely hit supersonic speeds let alone reach their top speeds. Due to the massive fuel consumption and drag from the weapons they cruise at subsonic speeds to get decent range.

As a result they have tuned the fixed inlets of the F-35 to low supersonic speeds as it anything faster will not be used anyway and it would only reduce the low speed thrust of the aircraft. The F-35 will accelerate from Mach 0.9 to 1.5 just as quick as the Eagle due to this speed being inside the fixed inlets speed range. The F-15 could then keep accelerating infront of the F-35 but it wont due to fuel reasons. So the F-15 wont travel any quicker.

The F-22 is quite unique that its fixed inlets are tuned for higher supersonic speeds buts this is due to its ability to reach these speeds at dry thrust levels. The drag that is produced on an aircraft as it passes Mach 1 goes through the roof this is caused the transonic region. Travelling at Mach 1.2 the aircraft is travelling 50% faster than at Mach 0.8, however the drag on most 4th generation aircraft will be 100% greater. So the range is reduced significantly. However once you get up to Mach 1.6 the drag is actually LESS than at Mach 1.2. So you are now travelling 100% quicker than Mach 0.8 yet the drag may be only 80% greater. So the aircraft can actually get similar range at mach 1.6 as at mach 0.8 which is insane.

The only problem is that most aircraft have to use afterburners to hit Mach 1.6 so the range is significantly reduced. As they cant reach this speed they then have to eitehr travel at Mach 1.2 and put up with massive drag increase or drop right back to Mach 0.8 again.

This is why the F-22 is the only aircraft that can truely supercruise. It is the only aircraft that can pass the high drag transonic region without using afterburners so it can cruise long distances at supersonic speeds. The Eurofighter, Rafale and Gripen cannot completely exceed this high drag transonic region so they will not be able to cruise long distances. The Eurofighter is the second fastest though it can comfortably go supersonic at dry thrust levels however the range will still be reduced so it will probably only do it for part of the mission.

The F-35 will apparently hit Mach 1 at 100% dry thrust levels but due to the extra drag it will cruise at Mach 0.9 which is 90% of the speed but require only 80% thrust giving better range. This is the exact speed class as the F-15/16 Mig-29/SU-30 they all cruise around at Mach 0.9 at 70-80% thrust levels and only burst to low supersonic speeds. The F-35 can do this with ease in fact below Mach 1.5 it will probably travel more effeciently allowing it to have a travel supersonically more often than the teen series.

 

[Pingu]

F-15 Eagle, you believe that both the F-22 and F-35 order should remain uncut and that a 2018 heavy bomber needs to be developed, but remember, all of these are fighting for funds and one or more will have to be cut. I believe that a cut in the F-35 order will be less damaging than a cut in the F-22.

It would be a shame that so much money has been spent in developing the aircraft for only 183 to be developed, an amount which is too small for the Raptor to be full worthwhile considering that a force that small can't be in enough places at once. The comparison which has recently been made to the Me262 (built in too few numbers to have any major effect on the war) illustrates my point perfectly. Also, the cost per F-22 at 183 planes will be over $300M, with a larger order, this would not be the case.

Cutting the F-22 would also mean that the USAF would have half of its fighter force
1) Not having an edge over future threats
2) Maintainence heavy
3) Without replacement

Also, by the time the "Golden Eagles" are retired, the F-35s will be even less sufficient a replacement. I believe that a combination of the 2018 bomber and F-22s can fill the gap of an F-35 cut better than the other way round.

I also agree with you on the 2018 bomber concept/FB-22, though I don't see any difference between directly or indirectly replacing the F-15E, it still gets replaced by something so whats the difference between directly or indirectly replacing the F-15E?

By directly, I mean on a one-for-one basis or similiar. By indirectly, I mean that the abilities of the 2018 bomber would negate the need for the F-15Es to be replaced. The difference of whether it get directly or indirectly replaced is enormous: it would determine whether an aircraft needs to be developed i.e. the FB-22.

 

[Pingu]

rjmaz1, you have made some good points about the typical combat speed of the F-35. However, you say that an F-35 would be able to accelerate from 0.9 to 1.5 quicker than the F-15 because its fixed inlets are optimised for those speeds. Fixed inlets are better for stealth and weight, but at the cost of the performance being at its optimum through a its full range of speed. Just as the F-35s engine is optimised at lower supersonic speeds, the F-15s engine must surely be inherently optimised at low subsonic speeds due to the fact that its inlet will vary according to the speed it is travelling at.

The F-35s reduced drag, will give it a greater average speed and range over the entire combat mission but in the rare case of an engagement, I am not sure that an F-35 at full afterburner will outperform an F-15 at full afterburner (with jettisoned fuel tanks and greater thrust). I am starting to agree with you however that generally, the F-35 with advanced sensors, stealth, higher average combat speeds, helmet mounted sighting etc make the F-35, overall, a better air-air fighter than the F-15C but bear in mind that it is future threats that need to be addressed and the margin of improvement over the F-15 will need to be much greater than the F-35 currently offers (I am talking solely in terms of an air-defense platorm). The F-22 could be more easily adapted to perform the F-35s strike tasks than the other way round because to do so would require the airframe to be fundamentally be re-designed.

 

[F-15 Eagle]

F-15 Eagle, you believe that both the F-22 and F-35 order should remain uncut and that a 2018 heavy bomber needs to be developed, but remember, all of these are fighting for funds and one or more will have to be cut. I believe that a cut in the F-35 order will be less damaging than a cut in the F-22.

It would be a shame that so much money has been spent in developing the aircraft for only 183 to be developed, an amount which is too small for the Raptor to be full worthwhile considering that a force that small can't be in enough places at once. The comparison which has recently been made to the Me262 (built in too few numbers to have any major effect on the war) illustrates my point perfectly. Also, the cost per F-22 at 183 planes will be over $300M, with a larger order, this would not be the case.

Cutting the F-22 would also mean that the USAF would have half of its fighter force
1) Not having an edge over future threats
2) Maintainence heavy
3) Without replacement

Also, by the time the "Golden Eagles" are retired, the F-35s will be even less sufficient a replacement. I believe that a combination of the 2018 bomber and F-22s can fill the gap of an F-35 cut better than the other way round.



By directly, I mean on a one-for-one basis or similiar. By indirectly, I mean that the abilities of the 2018 bomber would negate the need for the F-15Es to be replaced. The difference of whether it get directly or indirectly replaced is enormous: it would determine whether an aircraft needs to be developed i.e. the FB-22.

You are right on having 381 F-22's, and building the 2018 bomber/FB-22, if they cut the F-35 order to 1300 they can still replace the F-16 on a one for one bases and keep the A-10, but the problem is if you cut the order of plans to be bought it will only dive cost through the roof and you will still pay more money to buy 1300 JSF than you would by paying for 1763 JSF. I mean look at the F-22 for example, they cut the order to 183 jets and the jets became 10 times as expensive I don't know why, thats why they should not cut the order in the first place. So you wont save any money by cutting the F-35 order, you will only be paying more for less airplanes and it makes the problem worse not better.

 

[F-15 Eagle]

Again you completely misread my post, i think the idiot comment is starting to stick.

You are incorrect if you think the F-15 can travel Mach 2.5 in combat. The F-15 set that speed on a single high speed run with no weapons. It hit Mach 2.5 and then had to stop and land as it had run out of fuel. I already stated this.

The F-15 has never exceeded Mach 2 in combat let alone Mach 2.5.

Again the fastest speed a USAF F-15 has reached in combat was Mach 1.6 and that was chasing MIG-25'S. The mig-25's weren't even travelling Mach 2 either no where near the Mach 2.83 top speed... I'm trying to find the source now.

So if what you say is true that the top speed that a jet can go but not in combat such as the F-15 never goes past Mach 1.6 even though it can go Mach 2.5, than the F-35 will never go past Mach 1 in a combat mission, even though it can go at Mach 1.6-1.8. The SU-27/30 and Mig-29 are capable of traveling at Mach 2.35 but I guess they will never go past Mach 1.5 so to say. Can you provide a link or website to prove this?

 

[rjmaz1]

So if what you say is true that the top speed that a jet can go but not in combat such as the F-15 never goes past Mach 1.6 even though it can go Mach 2.5, than the F-35 will never go past Mach 1 in a combat mission, even though it can go at Mach 1.6-1.8. The SU-27/30 and Mig-29 are capable of traveling at Mach 2.35 but I guess they will never go past Mach 1.5 so to say. Can you provide a link or website to prove this?

That is not correct. The reason why the F-15 doesn't go to Mach 2.5 in combat is because of drag of external weapons and the limitations on fuel. So it cant reach its clean top speed in combat instead it can reach roughly 2/3 of its top speed or Mach 1.6. The F-35 does not have these limitations so it will not be limited to Mach 1 like you say which would also be roughly 2/3 of its top speed.

The F-35 will be able to reach its top speed in combat config as its internal weapons provide no extra drag. So in combat config it has no extra drag compared to top speed config. Fuel and drag of weapons is not a limiting factor on the F-35's top speed it is the air inlets that are holding it back. The F-35 will actually be able to reach its original top speed of Mach 1.6 in combat as it has the fuel and has no extra drag of weapons.

September 11 it only hit Mach 1.5Notice the slow speeds of both the F-16 and F-15.. By the time they take off at 150 knots climb and accelerate to Mach 1.5 they'd be already running low on fuel. Notice how the average speed of the F-15 was calculated to be 510mph. The F-15 umay have hit Mach 1.5 but the averages across the entire flight including takeoff it was only 510miles per hour.

The Mig-25 chase i cant seem to find the transcript anymore, though it has been mentioned without speeds. This was when the EF-111 ravens were shot at and had to abort mission resulting in a F-15E getting shot down. The F-15C's chased and failed. The speeds mentioned surpised me at the time.

The F-35s reduced drag, will give it a greater average speed and range over the entire combat mission but in the rare case of an engagement, I am not sure that an F-35 at full afterburner will outperform an F-15 at full afterburner (with jettisoned fuel tanks and greater thrust).

Afterburners are used in bursts of a few minutes or even seconds at most.

The F-15C at full afterburner will be consuming 50% more fuel relative to its internal fuel load. A typical afterburner burst is used to bring the aircraft up to speed for an angagements. The F-35 will be able to keep full afterburners on for say 3 minutes where as the F-15 would be limited to only 2 minutes of afterburner to use the same amount of fuel. Of course the F-15 could use afterburners for thesame time as the F-35 but it may not make it back to tanker afterwards
That extra 1 minute of afterburner will see the F-35 keep up or even exceed the F-15's speed, providing the F-15 stays below Mach 1.6 which has been proven to be the case.

The F-22 would be a better replacement for the F-15E, it would be a significant improvement in every area. However the F-35 will also offer an improvement in every area though in some aspects only very minor improvements.

 

[Pingu]

You are right on having 381 F-22's, and building the 2018 bomber/FB-22, if they cut the F-35 order to 1300 they can still replace the F-16 on a one for one bases and keep the A-10, but the problem is if you cut the order of plans to be bought it will only dive cost through the roof and you will still pay more money to buy 1300 JSF than you would by paying for 1763 JSF. I mean look at the F-22 for example, they cut the order to 183 jets and the jets became 10 times as expensive I don't know why, thats why they should not cut the order in the first place. So you wont save any money by cutting the F-35 order, you will only be paying more for less airplanes and it makes the problem worse not better.

The reason that the cost per aircraft goes up if you reduce the production is because of the research and development costs. Remember, the research and development has already been done and that cost is now fixed at a very high number.

If the USAF were to buy one aircraft, the cost of that one aircraft would be the billions spent on developing it and then the amount spent on manufacturing it. If however, 1000 were built, the billions spent on R&D would be divided by 1000 and therefore drive the cost per plane down enormously.

Also, a higher rate of production also reduces the cost of actually manufacturing each aircraft. I don't know why this is but I imagine it is because of fixed overhead manufacturing costs (factories, machinery etc) which would obviously run along the same principle as the R&D costs. Apparently LRIP aircraft are the most expensive.

So if the F-35 order was cut, the total cost of all the aircraft would not increase, but the cost per aircraft would. This is why the F-22 is now stated at over $300M each.

rjmaz1, I am starting to agree with you that the F-35's ability to operate at its optimum performance is more important than a better peak performance. The 9/11 example is a good example and makes a good point. The F-35 will be superior to the F-15C is almost every respect. However, I do still stand by the fact that at absolute maximum perfomance with fuel tanks jettisoned (with only be the drag penalty of the weapons) and enough internal fuel present, the F-15C is superior.

Of course, in most situations, such as 9/11 where the aircraft needs to travel over great distances to engage where the two conditions I've mentioned would not be possible for the F-15C, the F-35 would be better. But in the case of say a CAP, with nearby tanker support and a short engagement over a short distance, the F-15 would not be impeded and would perhaps be able to get to its peak performance where it would be superior to the F-35. But yes, In almost every other respect the F-35 is superior, but perhaps not superior enough to be considered sufficient replacement for the "Golden Eagles" in 2025 or whatever it is.

 

[swerve]

... the problem is if you cut the order of plans to be bought it will only dive cost through the roof and you will still pay more money to buy 1300 JSF than you would by paying for 1763 JSF. ....

You're making a basic error here. You're confusing unit price with total price. Reducing numbers will increase unit price. It will decrease total price.

A simple (& rather simplified) explanation.

Fixed costs (R&D, setting up production facilities) are just that, fixed. They are not affected by how many are bought (though the cost of setting up production facilities depends on how fast you plan to build).

Variable costs (labour, parts, materials) are mostly dependent on the number bought, though for various reasons the relationships is not strictly linear. For example, the overheads of running a factory will relate more to the time it operates than how much is produced in it, so the overhead per unit of producing 500 aircraft in 10 years will be less than the overhead per unit of producing 250 aircraft in 8 years. But the total overhead, & therefore total cost, will not increase when numbers are reduced, & can decrease.

Therefore, if you reduce orders, you will reduce total costs, but each unit will cost more.

 

[F-15 Eagle]

but perhaps not superior enough to be considered sufficient replacement for the "Golden Eagles" in 2025 or whatever it is.

I would hope they would have more funding for more F-22's by that time in 2025 to replace the F-15. Maybe a new and better aircraft than the F-22, its 20 years from now so who knows.

 

[swerve]

I would hope they would have more funding for more F-22's by that time in 2025 to replace the F-15. Maybe a new and better aircraft than the F-22, its 20 years from now so who knows.

What - re-open the F-22 line 15 years after it closes? Doesn't seem very likely to me. In order to buy F-22s in 2025 you don't need only funding in 2025, you also need funding every year from 2010 to 2024, to keep the line open. That does not currently look likely.

 

[rjmaz1]

I would hope they would have more funding for more F-22's by that time in 2025 to replace the F-15. Maybe a new and better aircraft than the F-22, its 20 years from now so who knows.

The delays in the F-35 has free'd up a few extra years of procurement money before the F-35 hits full scale production. As the F-35 will now take longer to replace the older aircraft the USAF will get a capability gap similar to Australia.

The USAF in my opinion is 99% likely to continue F-22 production for ATLEAST 2 years extra, so 250+ aircraft seems likely. The current order is paying off the development costs. Additional F-22's would be significantly cheaper than the current cost.

In fact additional F-22's will most likely cost LESS than the low rate initial production F-35's. So until the F-35 hits full scale production and becomes cheap then the F-22 is the only option.

As the F-35 is still a long way off the F-22 may have an even brighter future.

 

[Pingu]

Thank you swerve. You managed to explain the unit price issue far better than I could (I found it difficult).

As I said, I think it would be far easier for the F-22 to fill the gap of the F-35 easier than the other way round. I think I have said this twice now so I apologise for being repetetive. It would be possible for the F-35s DAS and EOTS to be installed on the F-22 which would not only greatly improve the F-22s ground attack ability but also provide it with an IRST which it does not currently have.

There is an article that I would like to post on here but I need permission from a moderator first (and I don't know how to go about it). The author of the article basically explains in great detail why he thinks the F-35 order ought to be cut and gives a great explaination of possible alternatives.

 

[Aussie Digger]

Officials Begin to Clear F-15Es to Full-Mission Status

LANGLEY AIR FORCE BASE, Va. --- Air Force F-15E Strike Eagle aircraft are now undergoing a safety inspection that will return them to flying status according to an order issued Nov. 11 by Gen. John Corley, the commander of Air Combat Command.

Each of the 224 E-model aircraft require the completion of a 13-hour time-compliance technical order that inspects hydraulic system lines, the fuselage structure, or longerons, as well as structure-related panels.

General Corley ordered all F-15 models grounded after the mechanical failure and crash of a Missouri Air National Guard F-15C Nov. 2. The F-15s were grounded based on suspected structural fatigue in the Air Force's remaining 665 aging F-15s. The E-models are the Air Force's latest F-15 aircraft and average about 15 years in age.

"We were able to determine, based on initial reports from an engineering analysis, that the F-15E is not susceptible to the same potential cause of the Missouri mishap," said Col. Frederick Jones, ACC Combat Aircraft Division chief.

The TCTO inspection, he said, is designed to confirm the engineering analysis. "Our inspections will be very methodical and thorough ... safety is an essential focus," Colonel Jones said, assuring the F-15Es will not be "rushed" back to flight.

Although the F-15E models are newer, they only represent about one third of the Air Force's F-15s. The older majority of the F-15s are of more concern for Air Force officials.

"What we've got here is an example, in the C model, of what happens when you have an airplane that's about 25 years old," said Maj. Gen. David Gillett, ACC director of logistics.

The Nov. 2 crash also demonstrates the importance of recapitalizing the Air Force's fighter fleet, said the general. ACC's current fleet is the oldest in Air Force history. New systems are more capable, cost less to operate, require fewer people to maintain and can survive modern threat environments, ACC officials have said.

According to General Gillett, it's not just flight safety that draws concern on the aging F-15, but the mounting maintenance costs.

"What you find is that it becomes more and more expensive to modify [the F-15 airframe] over time," he said "Our costs have gone up 87 percent in the last five years and continue to rise rapidly. Even when you invest in an old airframe, you still have an old airframe."

The 13-hour maintenance inspection is being conducted at each location where the F-15Es are located. According to Colonel Jones, inspections of the E-models in the Southwest Asia area of responsibility have been completed already. Colonel Jones said a similar process will take place for the remaining models (A through D) of the F-15, which are approximately two thirds of the F-15 fleet. Specific details of that inspection are being worked out by ACC engineering experts.

Meanwhile, Air Force officials have stated they will remain engaged in meeting their worldwide mission requirements with safety as the "number-one essential focus." Officials in ACC said the command continues to ensure the integrity of all air sovereignty alert missions and protection of the United States from air attacks.

-ends-

Obtained: www.defence-aerospace.com

Seems the USAF DOESN'T agree with APA...

 

[F-15 Eagle]

What - re-open the F-22 line 15 years after it closes? Doesn't seem very likely to me. In order to buy F-22s in 2025 you don't need only funding in 2025, you also need funding every year from 2010 to 2024, to keep the line open. That does not currently look likely.

Well than they might build a new aircraft, I do know that the F-35 is not designed to replace the F-15, they could get funding starting in 2025 so the F-15's will remain in service for a few more years before the second batch of F-22's enter service.

 

[rjmaz1]

Well than they might build a new aircraft, I do know that the F-35 is not designed to replace the F-15, they could get funding starting in 2025 so the F-15's will remain in service for a few more years before the second batch of F-22's enter service.

Having a look at the F-15E's combat history it seems the F-35 is designed to perform the exact mission. So in effect it will be its direct replacement.

F-15E's during the gulf war hunted down enemy tanks and ground assets at night using its imaging systems. This is the primary role of the F-35A. F-15E's often performed the interdiction role again this is the primary mission of the F-35C. The F-15C provided air superiority with excellent beyond visual range capability. International customers will be buying the F-35 to provide this exact role just like the F-15C once did.

The F-22 was never designed to replace the F-117 yet it is now replacing it.

Once the non AESA F-15C's retire, what do you think will happen to the squadrons and pilots? You cant just make them redundant, they will transfer across to F-35's as no other aircraft combat aircraft will be in production. So in effect the F-35 will replace the F-15's that the F-22 does not.

Though who knows the F-15E's may stay around another 20 years and be replaced by the F-22's replacement.

 

[barra]

F-15E's during the gulf war hunted down enemy tanks and ground assets at night using its imaging systems. This is the primary role of the F-35A.

Not so sure about this statement. Once all the list of high value targets had been exhausted, aircraft were assigned a 50km by 50km killbox and the guys on the ground or AWACs directed them in as required for strikes on targets of opportunity. Imagine trying to control hundreds of aircraft roaming around at will doing whatever they like!!

Barra

 

[rjmaz1]

Not so sure about this statement.

"the Strike Eagle proved its worth in Desert Storm, carrying out deep strikes against high-value targets and providing close air support for coalition troops."

"During the war, F-15Es flew hunter missions during the night over western Iraq, searching after mobile SCUD launchers that threatened neighboring countries."

http://en.wikipedia.org/wiki/F-15E

Thats exactly what the F-35 is designed to do.

The F-35 has the speed, range and weapon load of the F-15E with the added bonus of AESA and Stealth. Im fairly certain the F-15E will eventually be replaced by the F-35 down the track.

I would take the list of aircraft the F-35 will replace with a grain of salt.

The F-22 hasn't been purchased in enough numbers to replace the F-15C's yet it had enough numbers to replaced the entire role of the F-117. The F-22 was never going to replace the F-117 they just found out that it could do the mission better. So once the F-35 comes online and outperforms the F-15E in every area then the F-15E will suffer the same fate as the F-117.