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This statement is factually incorrect. There is far more that goes into LO than just surface coatings. Otherwise, why not just coat F-16s and F-18s? Oh, wait, did that, didn't work. Not to the level JSF and F-22 are producing.

Yes, coating is not the only technology issue in LO. It is not even the number one issue, but still an important one in LO performance.

But from the first generation stealth aircraft experiences, the coating is the number one maintainance issue. How well the F-35 approach resolve this is to be seen. The approach LM used is a durable, low-maintenance stealth technology, using structural fiber mat embedded in the composite skin instead of the high-maintenance metallic paint of legacy stealth platforms like the SR-71 Blackbird or F-22. This avoids the need to use stealthy appliqués and coatings that come off in flight. Fiber mat is also part of the aircraft's load bearing structure.

For years, they tried to keep the JSF problem under wrap. Finally in 2008, they got a program manager who want to do the right thing by demanding realistic program management and projections, Gen. David Heinz. Well, they just shoot the messanger and forced Gen. David Heinz into retirement. LM already anounced that they will have cost and schedule projection that will look a lot better than the government estimate. :thumbsup:

Edited by Kei Lau
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Where have I dismissed anything? The only counterpoints I offer are to factual inaccuracies. I welcome all news on the JSF--if nothing else, it highlights the wildly different views in the media on the subject.

Sorry if you feel dismissed. You clearly have a far greater emotional investment on the subject than I do, and I will therefor limit myself to correcting factual errors and leave any attempts at humor out.

Mark, I will like to command you for doing a good job keeping factual accuracy. But you still missed some technical issues now and then, like the LO coating I replied elsewhere.

It is foregone conclusion that the F-35 will go into production. It embedded many second generation stealth technology that makes it a superior aircraft than the US lagacy design like the Eagle or the Super Hornet. The US war fighter need such an aircraft for the next 30 years.

The US forces train the pilots like nobody else. (May be except Israel.) That's how US stays to be the super power, not just building more hardware. The US aircrafts get used a lot even during peace time. The life cycle cost, combat ready rate are as important as the "on paper" performance specifications.

Lockheed Martin has suggested that the F-35 could also replace the USAF's F-15C/D air superiority fighter and F-15E Strike Eagles in the air strike role. It can be loaded with external pylons just like the Strike Eagle.

The main question is whether the F-35 will dominate the sky and defend US interest in the next 30 years like the F-15 Eagle did in the last 30? Or it will become a movie star like the F-14 in "Top Gun" and then goes into early retirement? The way the program goes, I do not have that confidence about the F-35 yet.

The F-35 needs to prove itself in fleet operation to be an reliable and affordable airplane. An superior aircraft can become an inferior weapon system if the US Forces CANNOT keep enough of them in the air at affordable cost. Just consider why the F-22 production was capped at 187 planes and the B-2 at 21. Too expensive to buy AND too expensive to operate.

Edited by Kei Lau
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Note--not trying to pick on you, but there are a few statements here that need clarification.

LO means seeing your enemy before your enemy sees you. The SH is one of the best 4th generation fight in that regard due to its AESA radar and other electronic warfare systems. 5th generation fighter rely on surface coating to achieve the smaller radar crosssection. The big question is its durability in the fleet. The super cruise engine is another new item whose maintainance record need to be proved. Whether LM delivers the performance is TBD. For the good of our country, we all hope that they will.

The SH has a fantastic radar. The APG-81 on the JSF has already proven to be better. That shouldn't come as a huge surprise, being newer, but it does bear mentioning. I would love to see the APG-81 retrofitted on older jets, but the budget to support SH upgrades and buy JSF just ain't there.

As for LO durability, I can't go into detail. But I can tell you the JSF is 20 years later than B-2 and 15 years later than F-22 when it comes to LO coatings and LO maintainability. B-2 is a maintenance nightmare. F-22 is better. F-35 beats them both by many miles. There have been extensive environmental tests, stuff never done on B-2 or F-22 (neither operates in a salt air environment!). The Navy has a very specific concept of operations, and very stringent maintenance requirements the JSF is designed to. I can tell you F-22 LO wouldn't last on a carrier, F-35 LO is NOT F-22 LO, and F-35 IS designed to operate on a carrier.

Supercruise refers to going supersonic without using afterburner. That isn't the JSF, that's the F-22. The F-35 engine is derived from the F-22 engine, so it isn't as risky as a new development, as the F-22 engine is a fairly known quantity.

Yes, a 2 year slip is disappointing, but doubling the unit cost is project threatening. Developmental program always carries a number of risk. A good manufacturer manages those risk to keep schedule and budget. A bad manufacturer covers up the problems and asks for bailout when the problem explodes.

I would never argue LM has done anything but a terrible job managing the program. This is why I say they are delivering in spite of themselves. Great engineers, TERRIBLE managers (obviously).

We will see how it works out in the next major defense contract if EADS tries to low bid the tanker contract. Northrop Grumman withdrew and did not even file a complaint because they decide that the larger tanker cannot win on cost. In the 2008 competition, the lower life cycle cost number was not credited by the DoD because Boeing cost methodology was deemed too complex. NG asked for the Boeing cost information from the last competition and the DoD refused. NG withdrew shortly. Will EADS low ball the developmental cost to make up the difference? It is everybody's guess.

I'm guessing you have no idea how BAD that would have been if DoD had given proprietary cost data from one company to another. Boeing could sue the govt to the moon and back if they did something that wrong. The bigger issue with anything EADS is how much money the Euro govts have dumped into them to support them and make them competitive with Boeing.

Again, not trying to pick on you, but some of the questions you ask and statements you make indicate you may not have done all the research you should on these subjects.

The main question is whether the F-35 will dominate the sky and defend US interest in the next 30 years like the F-15 Eagle did in the last 30? Or it will become a movie star like the F-14 in "Top Gun" and then goes into early retirement? The way the program goes, I do not have that confidence about the F-35 yet.

The F-35 needs to prove itself in fleet operation to be an reliable and affordable airplane. An superior aircraft can become an inferior weapon system if the US Forces CANNOT keep enough of them in the air at affordable cost. Just consider why the F-22 production was capped at 187 planes and the B-2 at 21. Too expensive to buy AND too expensive to operate.

This is a big, scary question. I believe the USAF should be snapping up the latest Strike Eagles off the line--excellent bomb platforms, supportable, and will be perfect for the bomb truck duty the SH will end up doing. Neithe Strikes or SH stand a chance in denied airspace, but we also should be ready to fight the non-peer fights too.

Guess we'll see.

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As for LO durability, I can't go into detail. But I can tell you the JSF is 20 years later than B-2 and 15 years later than F-22 when it comes to LO coatings and LO maintainability. B-2 is a maintenance nightmare. F-22 is better. F-35 beats them both by many miles. There have been extensive environmental tests, stuff never done on B-2 or F-22 (neither operates in a salt air environment!). The Navy has a very specific concept of operations, and very stringent maintenance requirements the JSF is designed to. I can tell you F-22 LO wouldn't last on a carrier, F-35 LO is NOT F-22 LO, and F-35 IS designed to operate on a carrier.

That jives with what Navy and LM folks have told me... but interestingly, so too did industry officials from a couple of other firms.

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Just remember, and no joke, LM speaks with forked tongue once you get above a certain level. I don't put much faith in the blow-smoke-up-your-skirt statements (everything was rosy right up to the Nunn-McCurdy, now the CAPE and JET estimates are wrong, etc...)--I go with what has actually been demonstrated.

Yep--that article sums it up quite solidly. JSF was a yearly offender on the GAO top weapon systems hit list, and has been a case study on how NOT to do a program start. JSF in large part helped get the law changed requiring a certain mandatory level of technology readiness prior to program start, and also drove more/better prototyping (JSF "prototyping" was a joke considering what it should have done). A 2 year slip given all the warnings of disaster is a lot better than it should have been.

BTW, SH had some of the same "not ready for prime time" warnings by the GAO, so the GAO poking a program in the chest isn't always an accurate indicator. But the number of agencies and the direness of the warnings were truly spectacular for JSF.

Edited by MarkW
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Just remember, and no joke, LM speaks with forked tongue once you get above a certain level. I don't put much faith in the blow-smoke-up-your-skirt statements (everything was rosy right up to the Nunn-McCurdy, now the CAPE and JET estimates are wrong, etc...)--I go with what has actually been demonstrated.

I know this only too well, particularly with one particular person whom I shall not name here.

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There have been extensive environmental tests, stuff never done on B-2 or F-22 (neither operates in a salt air environment!).

Thought both the B-2 and F-22 routinely operated out of Guam. Would this not be considered a salt air environment?

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Note--not trying to pick on you, but there are a few statements here that need clarification.

Supercruise refers to going supersonic without using afterburner. That isn't the JSF, that's the F-22. The F-35 engine is derived from the F-22 engine, so it isn't as risky as a new development, as the F-22 engine is a fairly known quantity.

I would never argue LM has done anything but a terrible job managing the program. This is why I say they are delivering in spite of themselves. Great engineers, TERRIBLE managers (obviously).

Again, not trying to pick on you, but some of the questions you ask and statements you make indicate you may not have done all the research you should on these subjects.

Not sure about what are all the research that I should have done on these subjects. I have access to only PD (Public Domain) documents. Even if I know any classified information about the F22 or F35 (and I don't), I should not discuss them here. And the bulk of their technical details are classified.

It is common knowledge that the F22 and F35 engine integration have serious thermal management problems. To the extend that the USAF requested a SAB (Scientific Advisory Board) study on the issues in 2007. They released a PD version of the report in 2008 which is what I can research on. If you have access to the complete, classified version of the report, I admit ignorance.

The evolution of the engine design from F100 (F15, F16) to F119 (F22) then to F135 (F35) is an interesting story. The F35 does not have supercruise requirement and uses an engine derived from the F119 (supercruise) core. Something was overlooked in that process. I will not agree with you if you argue that the scheduling delay and budget overrun of the F35 have NO technical roots.

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Thought both the B-2 and F-22 routinely operated out of Guam. Would this not be considered a salt air environment?

Oh good golly no. The carrier environment really needs to be seen to be appreciated. This is a counter measure washdown:

DSC_2358.jpg

JSFs could be conceivably spooged on deck, and then get sprayed down with pure, unadulterated sea water--up into the gear wells, bay doors, etc. Ain't no F-22 or B-2 dealing with that sort of mess. And, F-22s been to Guam, what, once? When B-2s go, they have their own hangars to keep them out of the elements. Far more fragile LO than F-35.

It is common knowledge that the F22 and F35 engine integration have serious thermal management problems. To the extend that the USAF requested a SAB (Scientific Advisory Board) study on the issues in 2007. They released a PD version of the report in 2008 which is what I can research on. If you have access to the complete, classified version of the report, I admit ignorance.

Actually, it isn't, and your characterization is incorrect. The F-22 had some thermal issues they have dealt with. When F-35 hits Eglin next year, the one remaining thermal issue (which only affected one flight profile on hot days) will be resolved. I reviewed the 2007 study before it came out, and it was based on reasonable conclusions, but NOT on specific system performance. The report is basically a warning that if you button up a jet real tight, it will likely get hot and you need to prepare for it. F-22 had a problem that is fixed, F-35 resolved the problem before it became one.

For the record, the engine was not the issue. If anything, the engine is your friend when it comes to thermal management.

The evolution of the engine design from F100 (F15, F16) to F119 (F22) then to F135 (F35) is an interesting story. The F35 does not have supercruise requirement and uses an engine derived from the F119 (supercruise) core. Something was overlooked in that process. I will not agree with you if you argue that the scheduling delay and budget overrun of the F35 have NO technical roots.

What was overlooked? It was well understood what a single engine internal bomb bay fighter could do, even with 40,000 lbs of wet thrust, and single engine was a very intentional choice for fly away and lifetime costs. Just because an F-22 can suprecruise doesn't mean the F-35 should--they are different jets to do different missions.

I'm not saying there haven't been technical challenges on F-35. BUT, a better job at managing the program would have highlighted those issues earlier--I think I've been fairly consistent at characterizing the past management as atrocious. I will also say the vast majority of really hard technical problems on F-35 are solved, barring any new and exciting problems dug up in flight test (which is entirely possible considering how immature flight test is at the moment).

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Some of those delays as pointed out in that above article were of engineering origin also ... Such as the overweight problems ...

See, I never mentioned SH and yet you dragged it back into the conversation ... :)

When SH costs twice as much as first advertised, let me know ...

Gregg

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Some of those delays as pointed out in that above article were of engineering origin also ... Such as the overweight problems ...

Gregg

Yawn.

There is no such thing as perfectly designed plane, from the start. Unless you build something really easy. And modern fighters are sure as heck isn't easy. So baby diseases are usual. Superhornet had a wing drop problem i think, that is pretty serious.

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Superhornet had a wing drop problem i think, that is pretty serious.

In the older aircraft, any aeroelastic wing deflection would have been a serious "wing drop" problem.

Somehow, Boeing made this into a "flexible wing" feature of the Super Hornet. It makes a more efficient and maneuverable aircraft using active control of the roll and moment. Since the early production Super Hornet is pushing its original structural life limit of 6000 hours with no problem and the Navy is talking about 8600 hours. It may be more accurate to say "flexible wing feature" instead of "wing drop problem". It is an excellent example of the DARPA (Defense Advanced Research Projects Agency) high risk, high payoff motto.

If the active control logic for the flexible wing developed then did not work out as designed, it would have been a serious "wing drop" problem. We will not be talking about the Super Hornet today.

Boeing is not shy about talking the 787 flexible wing design too.

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It is common knowledge that the F22 and F35 engine integration have serious thermal management problems.

The evolution of the engine design from F100 (F15, F16) to F119 (F22) then to F135 (F35) is an interesting story. The F35 does not have supercruise requirement and uses an engine derived from the F119 (supercruise) core. Something was overlooked in that process. I will not agree with you if you argue that the scheduling delay and budget overrun of the F35 have NO technical roots.

Actually, it isn't, and your characterization is incorrect. The F-22 had some thermal issues they have dealt with. When F-35 hits Eglin next year, the one remaining thermal issue (which only affected one flight profile on hot days) will be resolved. I reviewed the 2007 study before it came out, and it was based on reasonable conclusions, but NOT on specific system performance. The report is basically a warning that if you button up a jet real tight, it will likely get hot and you need to prepare for it. F-22 had a problem that is fixed, F-35 resolved the problem before it became one.

I am not buying these official LM PR postions.

For the record, the engine was not the issue. If anything, the engine is your friend when it comes to thermal management.

What was overlooked?

If you are talking about the legacy fighters (F15, F16 and F18), this statement is true. When they designed the new F119 for supercruise, the "friend" was not longer there. The key word is "by pass ratio". If you don't know what I am referrring to as missing. That's ok.

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None of my information is based on LM, as I've mentioned previously. You can choose to ignore or dismiss any facts or data that don't fit your world view, I can't help that. Again...the engine is not the prime source of heat on these jets, it is the prime means of removing heat. Thermal management refers to the entire air vehicle, not just the propulsion. Legacy jets have ECS vents all over the place for heat exchange, hence no thermal management to even deal with. If you read the SAB thoroughly, you'd have noted thermal management is a new issue for 5th gen AC only for very specific reasons.

It doesn't matter how much bypass ratio you have if the net thrust isn't sufficient to propel the vehicle past the Mach barrier without going into afterburner. F-22s can do it because it is a cleaner design drag wise and it has way more dry thrust with two engines than JSF with one. Again, it was a design trade to use one engine for lower cost than to have two. Additionally, supercruise has absolutely nothing to do with either the F-22 or the F-35 thermal management issues. That you keep bringing it up indicates you are misinterpreting something.

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In the older aircraft, any aeroelastic wing deflection would have been a serious "wing drop" problem.

Somehow, Boeing made this into a "flexible wing" feature of the Super Hornet. It makes a more efficient and maneuverable aircraft using active control of the roll and moment. Since the early production Super Hornet is pushing its original structural life limit of 6000 hours with no problem and the Navy is talking about 8600 hours. It may be more accurate to say "flexible wing feature" instead of "wing drop problem". It is an excellent example of the DARPA (Defense Advanced Research Projects Agency) high risk, high payoff motto.

If the active control logic for the flexible wing developed then did not work out as designed, it would have been a serious "wing drop" problem. We will not be talking about the Super Hornet today.

Boeing is not shy about talking the 787 flexible wing design too.

....

What are you talking about? Wing drop =/= Flexible wing. Wing drop happened due to a certain AoA. Also, let me introduce you to:

http://www.allstar.fiu.edu/aero/images/F-111AFTI.jpg

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WSJ article on Defense Industry Braces for Cuts.

Another problematic program is the F-35 Joint Strike Fighter, the costliest fighter program in history, with a total price tag in the hundreds of billions of dollars. The versatile stealth aircraft, which is being developed by Lockheed Martin Corp., is supposed to replace many of the fighters in the current inventory.

Rep. Adam Smith (D., Wa), chairman of the House Armed Services Committee's air/land subcommittee, said the plane was "undeniably necessary." But he expressed concern about whether it could meet delivery goals. "If it meets the time frame, it's still very, very expensive and very, very difficult to get into a constrained budget," he said. "If it doesn't, we have to make some very hard decisions."

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I've been following this thread with interest. Not because I have any stake in the F-35, but I'm simply a concerned taxpayer. I see funds being spent on a program that isn't meeting the timeline.

The best way to explain is if you look over in the Bad Seller forums. You've got a bunch of people who paid for something and it wasn't delivered in the timeline outlined by the seller. In this case, this is the same as L-M. They won a contract for X amount of jets, at X amount of money, at X amount of time. So far, they've not met their end of the contract. That is what people want to know about. When are they going to deliver?

-JS

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