A Royal Air Force top gun crash-landed a new $136.3 million Typhoon fighter — apparently after forgetting to put the wheels down during a training exercise in California.

The state-of-the-art jet was badly damaged as it skidded along a runway on its belly at 130 mph.

"Everything points to the pilot forgetting to lower the wheels, which does happen from time to time," an RAF insider said.

Another possible cause of the accident is landing gear failure — but none of the other 48 Typhoons in service has been grounded with such a problem.

The top gun and his co-pilot from 17 Squadron climbed unhurt from the 1,500-mph jet. They were taking part in a major war games exercise at China Lake air base in California where aircraft can train with live weapons because of the remote location.

The mangled jet will be brought back to Britain to see if it can be repaired.

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