The metal door plug that flew off an Alaska Airlines Boeing 737 in midair last month was opened at a Boeing factory and reinstalled without several key bolts, federal investigators found Tuesday, as the airplane manufacturer faces intense pressure over safety concerns.
Inspections by Alaska Airlines and United uncovered loose bolts on door panels for grounded Boeing ... [+]
The lack of damage to the door plug—which fell an estimated 16,000 feet—suggests the four bolts intended to attach it to the plane’s fuselage were missing during the flight, the National Transportation Safety Board wrote in its preliminary report.
Months earlier, Boeing completed repairs for five damaged rivets in late August which required the bolts and the door plug—a metal panel that covers a hole in the fuselage sometimes used to fit doors—to be opened, according to the agency, which noted the damaged rivets were replaced and the bolts were not.
Photos included in the agency’s report show three bolts missing after the repair was completed in September, suggesting the plane flew without the bolts for nearly three months before the Jan. 5 incident (the spot where the fourth bolt should have been installed wasn’t visible in the photo).
The Seattle Times, citing anonymous sources, reported last month that Boeing failed to reinstall the four bolts before the plane was delivered to Alaska Airlines.
An investigation into the repairs and what documents authorized them is ongoing, the agency said.
Though the NTSB reported the door plug was missing bolts, the agency did not determine what caused the incident. A final report is expected sometime next year, according to Bloomberg.
In response to the report, Boeing CEO Dave Calhoun told CNN “Boeing is accountable for what happened,” adding, “An event like this must not happen on an airplane that leaves our factory.”
FAA Administrator Mike Whitaker told a House panel Tuesday the agency will “have more boots on the ground closely scrutinizing and monitoring” Boeing’s production and manufacturing, according to the New York Times. The agency’s inspectors were engaging with Boeing employees at “every phase of the manufacturing process” to better understand what pressures they face and how they receive instructions, Whitaker said.
On Jan. 5, Alaska Airlines Flight 1282 was forced to make an emergency landing in Portland, Oregon, after the door plug was blown off shortly after takeoff. Alaska Airlines and United later said investigations of their Boeing 737 Max 9 aircraft uncovered loose bolts on some of the door panels. The FAA ordered more than 170 Max planes to be grounded for inspections. Calhoun has said Boeing will “ensure every next airplane that moves into the sky is in fact safe,” while Boeing has contacted airlines with instructions to inspect aircraft with the door plug. Boeing has faced criticism over the incident, which comes years after two earlier 737 Max jets crashed in 2018 and 2019 due to a faulty flight control system, forcing all of the planes out of the sky for over a year.
Investigators Will Probe If Door Panel On Alaska Airlines 737 Max 9 Was Securely Bolted (Forbes)