The U.S. Air Force fleet of stealth F-22 Raptor fighter jets, which has never seen combat despite costing the U.S. government nearly $80 billion, has now been grounded indefinitely.
The order came down from the Air Force's Air Combat Command Tuesday due to "recent reports of potential oxygen system malfunctions," Air Combat Command Captain Jennifer Ferrau told ABC News.
"The stand-down provides Air Force officials the opportunity to investigate the reports and ensure crews are able to safely accomplish their missions," Ferrau said.
The grounding comes just days after a rare video surfaced featuring a flight by one of the F-22s closest potential air rivals, the Chinese J-20 stealth fighter.
But for U.S. forces in each of America's three current major combat operations, having the F-22s sitting on the sidelines will not make much of a difference -- other than training and patrol operations, that's where they've been since the first of the expensive planes went combat ready in December 2005.
When the U.S. led an international effort to secure a no-fly zone over Libya in March, the Raptors did not participate. The Air Force said the planes simply weren't necessary to take out Libyan dictator Moammar Gadhafi's air defenses.
"If this was a requirement, it would've been used," Air Force spokesperson Maj. Chad Steffey told ABC News then. "We had all the assets that we needed in Europe already... It simply wasn't an operational requirement."
In fact, though the Air Force has more than 160 F-22s, Steffey said that they have not been an "operational requirement" in any major theater of combat for the U.S., from Iraq to Afghanistan.
Not a single one of the planes -- which cost U.S. government $77.4 billion for a total of 187 planes from Lockheed Martin according to recent report by the Government Accountability Office -- has used what Lockheed Martin's website called a "revolutionary leap in lethality" in defense of U.S. interests.
In 2009, Congress cut all funding for new Raptors, stopping the orders at 187 operational planes -- the last of which are still being delivered -- compared to the more than 600 that were originally part of the deal. However, Lockheed Martin is still receiving hundreds of millions in taxpayer dollars to make upgrades to existing planes.
The closest an F-22 has come to combat was in 2007 when a pair of Raptors intercepted and monitored two Russian bombers that were on patrol in airspace near Alaska, according to a report by Air Force Magazine.
Defense Secretary: Plane 'Does Not Make Much Sense'... Yet
Both the Air Force and Lockheed Martin said the reason the planes have yet to fire on any enemies is because they're designed to dominate the air against rival, sophisticated air forces or air defenses, not a small, poorly armed third-world militaries and insurgent groups.
The planes' natural enemy, therefore, is one that the program's biggest critic, Defense Secretary Robert Gates, said as of now does not exist.
"The F-22 is clearly a capability we do need -- a niche, silver-bullet solution for one or two potential scenarios -- specifically the defeat of a highly advanced enemy fighter fleet," Defense Secretary Robert Gates said in 2009 while advocating that Congress ditch further funding for the Raptor from the budget. "[But] the F-22, to be blunt, does not make much sense anyplace else in the spectrum of conflict."
Dozens of supporters of the F-22 program in the House and the Senate wrote letters to President Obama ahead of the 2009 budget decision, arguing a full force of F-22s would be needed to meet the future challenge of other nations like China and Russia that are also developing fifth generation fighters and new, high-tech air defense systems. Gates dismissed these claims and said the U.S. next generation fighters, both the F-22 and the newer F-35, would greatly outnumber any adversaries for the next 15 years at least.
But the new J-20 video showed, according to Lockheed Martin, the "emerging threats" that prove the F-22s necessity.
"This [J-20] flight shows that other nations are seeking to develop the capability to challenge the F-22, and by extension, our capacity to attain air superiority in future conflict," a Lockheed Martin spokesperson said.
Jeff Babione, the vice president and project manager for the F-22 program at Lockheed Martin, told ABC News last month China and Russia's fighter programs were a consideration in the F-22's development, but also said the F-22 could find a home in strike missions against rogue nations like North Korea and Iran.
"[The F-22s] are in an area where they would be solely or more suited for a sophisticated adversary like North Korea," Babione told ABC News. "In particular, its ability to penetrate highly defended locations -- such as North Korea -- only the Raptor would be able to get in there and prosecute the missions."
In the meantime, Babione said the F-22 was "absolutely" a prudent investment for its value as a deterrent to potential foes and said he hopes the Raptors never do go to war.
"The best weapon is the one that's never used," he said.
News of the stand-down order for the F-22s was first reported by the aviation website FlightGlobal.com.