... mechanical problems with the Air Force's F-22 and now the F-35 have been grounded as well.
http://www.youtube.com/watch?v=XQmsLK2hMz8
And
F-35 grounded after electrical system failure thus joining the F-22
August 5, 2011 (by Lieven Dewitte) - For the third time in less than a year, the Pentagon has grounded all F-35 joint strike fighters because of a mechanical problem. The F-35s thus join the F-22 Raptors in stand down mode.