US F-35 fighter jets
© Flickr/ US Air Force
The F-35's many flaws have been well documented. But according to pilots, one aspect of the fifth-generation fighter works so well that it's actually causing new problems.

After months of delays, the US Air Force is expected to deem its F-35 variant combat ready this week. That status means that the fighters are undergoing new exercises to test the plane's capabilities and prepare pilots.

But the aircraft's state-of-the-art stealth technology is evidently making it difficult for the military to carry out those drills. Exercises performed at Mountain Home Air Force Base in Idaho were meant to test the plane's ability to evade surface-to-air missiles [SAM], but ground units had a difficult time locking onto the aircraft.

"If they never saw us, they couldn't target us," said Lt. Col. George Watkins, according to Defense News.

According to Watkins, ground units were only able to track the F-35 after pilots switched on FAA identification transponders.

"We basically told them where we were at and said, 'Hey, try to shoot at us.'"

He added that without the transponders, "most likely we would not have suffered a single loss from any SAM threats while we were training at Mountain Home."

These are bold claims for an aircraft that was, until recently, plagued with software glitches that caused it to shut down mid-flight.

"When we go to train, it's really an unfair fight for the guys who are simulating the adversaries," Watkins said. "We've been amazed by what we can do when we go up against fourth-gen adversaries in our training environment, in the air and on the ground."

While earlier tests showed that the F-35 was outperformed by older fighters, Watkins suggests otherwise.

Four F-35s, he claims, can "be everywhere and nowhere at the same time because we can cover so much ground with our sensors, so much ground and so much airspace. And the F-35s or F-16s, or whoever is simulating an adversary or red air threat, they have no idea where we're at and they can't see us and they can't target us.

"That's a pretty awesome feeling when you're going out to train for combat," he said, "to know that your pilots are in an unfair fight."

Last week, the US Air Force indicated that the beleaguered fighter may be deemed combat ready in the coming days.

"We have achieved all our milestones," said Lt. Col. Steven Anderson, according to Defense News. "We have submitted all of the data to ACC [Air Combat Command] for General [Herbert] Carlisle's consideration on making that declaration."

The US Marine Corps expressed similar confidence in its F-35B variant.

"We've got a jewel in our hands and we've just started to exploit that capability and we're very excited about it," Deputy Commandant of the Marine Corps for Aviation Lieutenant General Jon Davis said during a discussion at the American Enterprise Institute.

"The bottom line is everybody who flies a pointy-nose airplane in the Marine Corps wants to fly this jet."