Both US operators of Boeing 737 Max 9 aircraft are finding loose parts in the aircraft during the latest inspections that were prompted by an emergency exit door plug blowout during flight over the weekend.

United Airlines and Alaska Airlines, the latter of which operated the flight on Friday that experienced the three-mile high emergency exit blowout shortly after takeoff, independently reported "loose hardware" discovered around the emergency exit plugs on their 737 Max 9 aircraft.

"Since we began preliminary inspections on Saturday, we have found instances that appear to relate to installation issues in the door plug - for example, bolts that needed additional tightening," a United spokesperson told The Register. Alaska Airlines said in an update regarding the incident that "some loose hardware was visible on some aircraft" around "the area in question."

Both airlines said their 737 Max 9 fleets will remain grounded until FAA-mandated inspections, repairs, and recertification is complete. The timeline for the process is unclear, and in the meantime United has been forced to cancel 200 Max 9 flights, a few of which it was able to reschedule by switching to other aircraft. Cancellations are expected to continue today, United said. 

United operates 79 and Alaska 65 of the 737 Max 9 aircraft, making them the only major US airlines with this model in their fleets. Panama's national carrier Aeromexico, Turkish Airlines, and Icelandair also fly smaller numbers of the aircraft.

According to aerospace news outlet The Air Current, the location of loose parts on the United Airlines aircraft is relatively inconsistent, with one aircraft having loose bolts on the lower hinge of the plug door, leading to the hinges not being fully seated. On another aircraft, United reportedly found loose bolts and screws on forward guide fittings and lower hinge brackets on the plug.

The inspections performed by United and Alaska were done over the weekend preliminarily, we note, and it wasn't until Monday that the FAA approved a method to comply with the emergency airworthiness inspection requirements issued on January 6.

The plug blowout, and accompanying firestorm of negative media attention, is unlikely to help Boeing or the 737 Max's reputations. It was just a few years ago that a pair of 737 Max crashes (in earlier variants of the model) grounded the fleet and led to a damning report that found the incidents, which killed 346 people, were partly the result of serious oversight failures with a side dose of safety concern issues.

When asked to comment on the matter, Boeing only referred us to its 737-9 incident update page, which contains little detail about the blowout or the findings from preliminary investigations.

"As operators conduct the required inspections, we are staying in close contact with them and will help address any and all findings," Boeing said. "We regret the impact this has had on our customers and their passengers." 

Boeing will host an all-hands meeting today at its factory in Renton, Washington, to address the aerospace company's response to the incident and its "commitment to safety, quality, integrity and transparency," said CEO Dave Calhoun.

"While we've made progress in strengthening our safety management and quality control systems and processes in the last few years, situations like this are a reminder that we must remain focused on continuing to improve every day." ®

https://www.theregister.com//2024/01/09/united_alaska_737_loose_bolts/