US airstrikes in Syria against Isis
Photo shows before and after photos of target by F-22. This was the first time the F-22 was used in a combat roleUS Department of Defense

The US Air Force has unleashed Pentagon's most sophisticated fighter jet, the F-22 Raptor for the first time ever in any combat zone following a decade-long wait.

The F-22 project cost about $68billion and the jet is the most expensive plane in the US military's possession.

Roaring in the air alongside its F-15 and F-16 cousins, the fifth generation aircraft pounded Isis targets in Syria and Iraq, although the exact places of bombardment were not revealed by the Pentagon.

The luxury vehicle was never brought into the airstrikes previously, largely because its cutting-edge capabilities were not needed for the targets the US had been focusing in the past decade.

The use of such advanced aircraft against the Isis has come as a surprise to some aviation experts. A US Air Force official told the Wall Street Journal: "The ultimate decision being made—that we are to use this aircraft against an adversary—is a unique and momentous decision for the United States Air Force."

"It has a unique ability to approach adversaries in a way legacy aircraft can't. There are things the F-22 is uniquely suited to address that the other fighters in our inventory can't."

One of the key reasons for employing the radar-evading stealth gear is thought to be to avoid detection by Syria's defence capabilities.

The US bought 188 jets from the makers Lockheed Martin and reportedly has no plans to buy more.

US airstrikes targeting Isis positions in SyriaUS Department of Defense