This was supposed to the be the F-35’s big month.

The troubled next-generation fighter jet was going to make its international debut at the Farnborough Air Show in England. The U.S. and its partners would have something to show for their years of delays, setbacks, and cost overruns.

They would have nothing less than a functioning version of the most advanced warplane in history.

This potential breakthrough has hit an all-too-typical stumbling block.

The Air Force temporarily suspended all F-35 flights after one of the planes caught on fire before takeoff at Eglin Air Force Base in Florida. Even if the plane does debut later this month, it still has some serious issues, and a long way to go before it can be rolled out for combat missions. Already, the plane is expected to be delayed for over a year beyond its projected mid-2015 delivery date.

Despite this, it’s not likely that the F-35 will ever be scrapped. As we reported back in November of 2012, there are simply too many countries that have invested time and money into the program.

It is, quite literally, an aircraft that is “too big to fail” despite facing lifetime operating costs for the U.S. Fleet of $US1 trillion, and cost overruns of $167 billion before a single plane has flown a single mission.

We’ve gone back and looked at the biggest problems with the F-35 program, according to an official Pentagon report.

Developed by Lockheed, the fighter has three variants: the conventional F-35A for the Air Force; the F-35B for the Marine Corps, which can take off and land vertically; and the F-35C for the Navy, a carrier version. If all goes to plan, the Pentagon is on track to spend a huge figure of $US396 billion on the jets, including R&D. It doesn't help that the cost to build each F-35 has risen to an average of $US160 million from $US69 million in 2001. The project is an astounding $US167 billion over-budget. More amazing than the cost of fabricating the F-35s is the expense of operating and supporting them: $US1 trillion over the planes' lifetime. Ranking member of the Senate Armed Services Committee, Sen. John McCain, described that estimate as 'jaw-dropping.' In 2011, the plane was grounded twice with electrical problems. One incident in August of 2012 resulted in a complete failure of the aircraft's integrated power package, which combines the functions performed by an auxiliary power unit, emergency power system, and environmental controls. Developers have also discovered major issues with its software, which Air Force Maj. Gen. Christopher Bogdan once called 'the gorilla in the room.' And it's supposed to fool enemy radar with stealth capabilities. But stealth coatings have been found peeling off, and the Pentagon report mentions -- but does not describe -- a 'classified' deficiency. Bill Sweeney of Aviation Week says, 'dollars to doughnuts it has something to do with stealth.' One variant of the F-35 has shown cracks underneath its fuselage, making many wonder if it can handle the rigors of future air combat. The concept of operational tradeoffs is a tricky one with the F-35 -- the more problems get fixed, the more normal the plane seems to be. The possibility of the fueldraulic system catching fire and incapacitating the pilot was discovered and remedied in 2008, but the fix gave the F-35 a 'vulnerability posture no better than legacy aircraft.' The Pentagon also 'expressed concern' in its report that it's no better than legacy aircraft in some close air support capabilities. Basically, if you are on the ground in a firefight, you might not be jumping for joy if you find out an F-35 is coming in. The advanced helmet is supposed to let pilots see data from all the plane's sensors, effectively allowing the pilot to look right through the floor of the plane and all around it. But it has big problems with night vision, delays in displaying data, and even jitter, under certain conditions. Pilots have noticed a green glow at the visor's edges and problems with alignment. Lockheed and The Pentagon aren't getting along so well either. The relationship 'is the worst I've ever seen, and I've been in some bad ones,' said Maj. Gen. Christopher Bogdan in September 2012. 'I guarantee you: we will not succeed on this if we do not get past that.' All of these issues have Congress' eye as well: On the senate floor, John McCain said, 'in a nutshell, the (Joint Strike Fighter) program has been both a scandal and a tragedy.' The problems with the F-35 make many wonder why The Pentagon continues with the program. See The Most Advanced Drone Camera In The World >

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