On April 20th 2008, an American Airline’s airplane (Boeing 767) took off from Dallas Fort Worth Airport for Paris. While climbing up to the cruising altitude a 3-foot by 6-foot panel made of composite material feel of the plane’s belly. Though it wasn’t till the plane reached Paris that the loss was identified.

From here

“[It] sounded like an explosion, or very large landing gear being
ripped,” said a flight attendant on board, according to an e-mail
obtained by television station WFAA in Dallas.