Bolts supposed to secure door were missing, investigation report finds

A series of setbacks for Boeing. Several bolts supposed to block the door of a 737 MAX 9 which detached in mid-flight in early January during a trip by the American company Alaska Airlines were missing, according to the preliminary investigation report from the Air Safety Agency. Transportation (NTSB), published Tuesday February 6.

According to the NTSB, the absence of wear or deformation around certain holes “indicates that four bolts intended to prevent the cap holder from moving upward were missing before it moved”.

The agency has collected written documents and photos that show Boeing employees removed four bolts at these locations during an inspection at the Renton, Wash., factory before delivery of the plane, in last October.

Several failures at Boeing

The operation was carried out to replace five damaged rivets in the cabin of the aircraft. Other photos taken after changing the rivets show that in at least three points, the bolts had not been reinstalled.

This door was used to block an exit and was not intended to be opened, this model already having enough emergency exits in this configuration. On January 5, she took off during the ascent of the Alaska Airlines MAX 9 which was to connect Porland, Oregon to Ontario, California. The incident left only a few minor injuries.

In recent months, Boeing has experienced other episodes of failure and in particular had to slow down its deliveries because of problems on the fuselage, in particular on the rear bulkhead of the aircraft.