h**p://www.dailystar.co.uk/news/view/76484/RAF-s-blunder-and-lightning/

It's those damn "sources" again.

 

Of course the real story is much more " mundane" and has been posted by Softwar:

Source:

"http://www.strategypage.com/militaryforums/6-55638.aspx"

F-35 May Need Design Changes for Thermal Management

Aviation Week & Space Technology Mar 30 , 2009 , p. 54

Upgrades to the Lockheed Martin F-35 Lightning II are being considered to improve the fighter?s ability to absorb heat from its powerful electronics and systems.

The aircraft is meeting the specification for thermal management, but the incoming Joint Strike Fighter program executive officer, U.S. Marine Corps Maj. Gen. (sel.) David Heinz, says he is asking contractors to assess the costs of changes to give it a bigger margin over the requirement.

The stealthy F-35 is designed to keep itself cool by dumping heat from the electronics and systems to its fuel. Under most conditions, that presents no challenge, but at the end of a mission the aircraft will have little fuel left to absorb the heat energy, says Tom Burbage, Lockheed Martin executive vice president for F-35 program integration. The toughest part of the specification is to distribute heat to the remaining fuel while operating in hot conditions.

?Thermal problems were first identified in hot-weather ground operations,? says a long-time Pentagon acquisition official. ?The problem was the fuel-air heat exchanger was not providing enough cooling. In the short term, at least, they?ll just limit hot-weather activity.?

As for the article's technical points:

This "huge problem" should be fixable.

 

 

 

 

 

 

 

 He is also quiet advanced in terms of knowlegebase and credential.

 

  He highlighted one (more) of F-35 problems and wrote about it, this problem CAN be fixed but it is a weak point.

 

  Anythnig that relies on fuel for cooling increased vulnerability to adverse fire.

This is an interesting trend. No other fighter has gone through development while under real time public scrutiny of this magnitude. No engineering project I've ever seen had gone flawlessly through development to production. This is not some insurmountable problem. Its simply one of many engineering challenges the F-35 and fighters like it face as testing reveals flaws in the original design. These designs are continuously revised and then things move until the product gets to a point where all of the shop stopping critical issues have been resolved and the trivial matters are waived as not serious enough to stop the program from meeting it's intent. People need to understand that and put these issues into context.

-DA 

  Sorry to say but put these issues into context, i did time and time AGAIN...

 

   Untill i got tired of reading that L-M had overshot their weight target by 35%, then limited the aiframes structural loads to compensate then got the aerodynamic wrong and had the same problem with vertical fin structural fatigue than F-18 more than 25 yeares ago, had to fit less stealth material to their main beam, had to reduce steaslth by fitting thinner winf skin, still haven't resolved the aerodynamic issue, didn't meet the 9 g requierement for two versions out of 3, faced electric failures due to bad CATIA design managerment, had engine blade failures etc.

  Tell me, into contest how many protoptype you eared of had so many problems, cost so much even in the US and still failed to meet their requierements because just for the story, these have been lowered since the first major design review.

 

  BTW i can provide you with proper links to well documented articles and interviews on EVERY issue i mentioned and i'm sure i forgot a few...

 

  Regards, PlG

Again, this is nothing particularly noteworthy with regard to meeting spec. This issue will be worked out, a new one will arise, the internet will run wild with peoples opinions, and sometime in early next decade the US and Allies will be flying around in the best all around fighter in the world. Again, context.

 

 "context".

 

  Sure but a very expensive and timely one, they didnt experienced this with the much more performant F-22.

 

Sure they did. Are you not familiar with the recent upgrades they have had to do with the 100+ F-22s that have already made it into the fleet? Things like this happen. Regression issues happen. Of course you try to prevent it. But it doesn't invalidate an entire program.  This is why we hire engineers. Considering the teething problems we've see in past platforms, INCLUDING falling out of the air, this is not something I'm too worried about. The testing done at this state is supposed to find issues like this. I'd be much more concerned about issues that make it through the development/LRIP phase and are only discovered through mishap after FOC.

-DA 

Well if you have some LM specific grievance by all means share. Otherwise, this is just another one of those things that happens with programs in development. The only difference is that we have much quicker access to the information. If you have been around long enough and followed other programs then this really isn't a surprise.

-DA 

The problems of the F-35 will undoubtly be solved (as with other troubled projects like the A400M). This particular one just represents overreaching and the illness of continual specification modifications. Thermal issues like this are particularly insidious because they affect or are affected by every subsystem installed. That being said - they not doubt make for interesting engineering exercises.

 

The true problem is not the ability of engineers to overcome engineering challenges but the larger challenge of politics. As pointed out previously, its the political ramifications that are the most dangerous. Anything issue that slows down, or hints at slowing down, development or increases cost at this time provides yet another load of fodder to the political animals who excrete the smelly stuff.

 

To be honest I don't think the heat issue is as big a problem as it is made out to be.

 

I have a hunch there are several directions in which the F35 design team could look for a possible solution. A hunch, because obviosly they are not gonna give me the F35 design data.

 

My gut feeling is that this is not such a big problem.

 

 

 

 

Pfff ... The most appealing thing is the fact that the F-35 still on the road map . It should have been dumped at the drawing board . It 's a dog ...

Coming from a Country who has made the B1 , the B2 and the F-22 , the pseudo F-35 is a disgrace and a theft for the Partners .

 

Cheers .

I don't think that F35 is a dog.

It is a very ambitious challenge considering that you have a supersonic stealth plane in 3 versions including a STOVL one.

And moreover you want it affordable so with a massive investment in manufacturing R&D.

No so easy.

A sort of F111 program of today (which was an interservice plane) but with the same problem of managing complexity.

I think moreover, that USA at begining put emphasys on Air to ground saying that F22 would do the job to clean the sky.

F35 was not supposed initially to be better than a F16 in flight performance.

 

I think that threat on F22 and foreign partners requirements have pushed for a better plane in AtoA with better electronic.

So some delays, a more heavier and costly airplane( but so much costly still), more power ...

Howewer the biggest weakness of F35 is still its global compromise.To get a huge internal bay to accomodate 1 tons AtoG weapons on a "small" fighter is an enormous penalty for high speed performance (frontal surface and area law) and it is not easy to achieve AtoA correct performance while staying affordable.

At the end US version will do the job for what they are intended for and USA will pay the price to fix problems.

But for export downgraded versions when you don't have a pure fighter aside like F22?

No wonder why Korean or Japanese are looking for their own fighter considering their  requirement is AtoA first.