A mystery in-flight upset of a LATAM Boeing 787 appears to involve the inadvertent movement of a pilot seat, because of a loose switch.

This accident happened on Friday the 15th of March, involving LATAM flight LA-800. The airline performs this flight daily, departing from Sydney Kingsford Smith Airport (YSSY) in Australia, at 11:35 AM. This is a two-leg flight, with a first stop at Auckland Airport (NZAA) in New Zealand. Its ultimate destination is Santiago International Airport (SCEL) in Chile.

On the day of this accident, the LATAM flight had 263 passengers and 9 crew on board. It departed from Sydney with a 10-minute delay, using runway 34R. The aircraft was cruising at FL410 when a sudden upset caused multiple occupants to hit the cabin ceiling.

When this upset happened, the flight was approximately 50 minutes away from its first stop in Auckland. Initial reports on the accident made no mention of a seat switch – instead, passengers reported hearing the captain saying that both 787 pilots briefly lost their instruments.

A 787 Pilot Seat Switch And A Cover

The flight landed safely on runway 23 in Auckland. As many as 50 passengers and crew suffered injuries, and 12 people in total needed hospital treatment. LATAM canceled the second leg of the flight to Santiago.

But later, Boeing messaged all 787 operators, reminding them of a previous message, regarding maintenance to the rocker switch caps, of the aircraft’s auxiliary switches for the pilots’ seats. Each 787 pilot seat has such a switch behind the headrest, under a cover (see above).

Maintenance crews need to check for loose switches, applying adhesive on them to secure them, when necessary. A loose switch could activate and move the seat, if someone simply presses down on the cover.

This suggests that someone may have inadvertently activated this seat switch on the accident flight, while a pilot occupied this 787 seat, likely sitting in an abnormal stance, causing the yoke to move forward. At the moment, this is still an assumption.

An investigation into this accident is underway. However, this LATAM 787 returned to service, two days after the accident. This is an eight-year-old Boeing 787-9, with registration CC-BGG. LATAM operates 26 of these jets.

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