Loose bolts found on grounded Boeing 737 Max 9 planes after Alaska Airlines incident
Both United Airlines and Alaska Airlines say they have found multiple loose parts on Boeing 737 Max 9 aircraft that were grounded in the wake of an alarming incident involving a window blowing out of a plane mid-flight.
The Federal Aviation Administration (FAA) grounded all models of the aircraft following the emergency on an Alaska Airlines flight from Portland that saw a large part of the fuselage being ripped from the plane at 16,000ft.
“Since we began preliminary inspections on Saturday, we have found instances that appear to relate to installation issues in the door plug,” United Airlines said in a statement. “For example, bolts that needed additional tightening.” The door plug is a specific panel of the fuselage near the rear of the aircraft.
“These findings will be remedied by our Tech Ops team to safely return the aircraft to service,” the statement added.
On Monday, Alaska Airlines also reported that a preliminary investigation by its technicians had revealed the presence of “loose hardware” on certain aircraft during routine fleet checks. Formal inspections are pending, awaiting final documentation from Boeing and the FAA.
Separately, it was also reported on Monday that the Boeing 737 Max involved in the Portland incident had experienced pressurisation warning lights on three prior flights. The aircraft had only been in service for two months.
The chair of the National Transportation Safety Board (NTSB) Jennifer Homendy told reporters that the auto pressurisation fail light had activated on 7 December, 3 January, and 4 January. However, she said it remained unclear whether there was any connection between those incidents and Friday’s rapid depressurisation incident.
United said it cancelled 200 flights using the model on Monday and expected additional cancellations on Tuesday. The company said it was able to avoid 30 cancellations each day by switching to other aircraft types.
The airline operates 79 Max 9 planes.
Reutersquoted a source familiar with the matter as saying that United had identified nearly 10 aircraft with loose bolts during its initial inspections. This is an increase from the initial five reported by Air Current, an industry publication, and there’s a possibility that the count may further rise.
The FAA declined to comment on the loose bolt reports.
On Friday, the door plug fell off the Alaska Airlines flight as it attempted to make its way from Oregon to California. The flight safely returned to Portland, where it had originated.
Some passengers were injured but were all later medically cleared by professionals, Alaska Airlines said in a statement.
Investigators have since recovered a part of the fuselage that blew out of the Alaska Airlines jet from the backyard of a school teacher in Portland, Oregon.
The National Transportation Safety Board (NTSB), which is investigating the incident, said that the part of the fuselage had been located on Sunday by a school teacher named Bob Sauer.
He reportedly sent the agency two photos of the wreckage in his backyard.
Over the weekend, the FAA announced it would be grounding all models of the Boeing plane to undergo inspection, which should take approximately four to eight hours per plane. The planes would only be returned to service after they’d been cleared by officials.
The Boeing 737 is the most successful aircraft with about 10,000 delivered.
The Alaska Airlines incident is the latest in a series of safety problems for the aerospace giant involving the 737 Max, its best-selling plane, since it was first introduced in 2017.
The aircraft were grounded around the world after two catastrophic crashes in 2018 due to an automated flight-control system called MCAS, resulting in 346 fatalities.
Boeing settled a Justice Department investigation for $2.5bn, acknowledging misleading regulators.
The 737 Max has also experienced problems with the rudder control system and anti-ice systems.
A recent incident involving an engine fire on a United Airlines 737 Max is still under investigation, along with an emergency landing in Wichita, Kansas, of a Denver-bound United Airlines flight on 14 December. Passengers reported hearing a rumbling and an engine fire was discovered after it landed. No one was injured.
The alarming event on Friday was reminiscent of a similar incident in 2011 on a Southwest Airlines flight travelling from Phoenix to Sacramento, California. During that episode, passengers experienced an explosion sound as a section of the aircraft’s roof opened at an altitude of almost 35,000 feet (10,700 metres).
The aircraft successfully made an emergency landing and no one sustained serious injuries. However, two people lost consciousness due to a lack of oxygen. That incident involved a predeccesor to the 737 Max, Boeing’s 737-300.
On Monday, Alaska Airlines cancelled 141 flights, constituting 20 per cent of its scheduled departures, due to the grounding of its 65 Max 9s. The airline says it expects travel disruptions to continue until at least mid-week.
United Airlines, which grounded its 79 Max 9s, cancelled 226 flights on Monday, about eight per cent of its scheduled departures. According to aviation analytics firm Cirium, out of the 171 planes affected by the order, 144 are currently in operation in the United States.
Additional reporting by agencies