British investigators say mechanics put a locking pin in the wrong hole and that allowed a British Airways Boeing 787 to drop on its nose on the ramp at Heathrow Airport last month. A crew member was slightly injured and millions of dollars in damage was done to the Dreamliner as the flight crew worked with mechanics and engineers to get the plane ready for a cargo flight. Before it could head to Frankfurt, the engineers needed to clear some warning lights relating to a minor and deferrable issue with a solenoid valve in one of the nosegear doors.
To clear the codes, the procedure involved cycling the gear up and down with locking pins in place to prevent the gear from actually moving. The procedure was done by the book except one of the mechanics put the pin in a hole right beside the one that would lock the gear. When the hydraulics were applied, the front gear retracted as it was told to do. The nose, gear doors and engine cowlings were damaged and a cabin door was ripped off its hinges when it contacted the air stairs. An airworthiness directive was issued in January of 2020 about the confusing hole placement after a similar mishap a couple of years ago, but operators had been given three years to comply.