Misplaced Pin Leads To 787 Gear Mishap


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.

Russ Niles
Russ Niles is Editor-in-Chief of AVweb. He has been a pilot for 30 years and joined AVweb 22 years ago. He and his wife Marni live in southern British Columbia where they also operate a small winery.

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  1. The story here in the UK is that the mechanic who knew which hole to put it in was rather short and so he asked the taller one to do it. The taller one didn’t know which hole to put it in! Design fail, training fail.

  2. I was impressed years ago when working near the avionics bay hatch of a B737 in Alaska.

    Probably a rough and ready airline, but I was impressed when a supervisor entered the hanger on Sunday, walked past the airplane, saw a main gear pin streamer laying on the floor, immediately directed a mechanic to fix that.

    I had noticed it in looking at the labelling of a switch on the gear, went back front to tell my colleague, intending to tell mechanics about it. The ace supervisor did it firsts. (No power on the airplane.)

  3. It’s good to keep your head on a swivel.

    I’m sure the supervisor had seen expensive gear incidents during maintenance before!

    I ended up being the maintenance test pilot at a busy flight school because I always seemed to notice what was broken first. Of course, the owner didn’t tell me for a few months why he was assigning me the airplanes that just came out of the shop. 🙂

    Most dangerous Mx incident was when flight control cables had work done, and the trim marking hadn’t been updated. Going vertical at 10′ over the runway really gets your attention.