Boeing In Max Trouble

After a grim initial entry into service, with two crashes, which between them involved more than three times the death toll of the de Havilland Comet 1, an aircraft which heralded the beginning of the jet age when rather a lot was still to be learned about metal fatigue and other side effects of the step change in speed, Boeing’s latest 737 variant was settling down to safe, routine service.

But not for the first time, this manufacturer has proved to be its own worst enemy, with another of those in-flight incidents which the airline industry, and especially consumer confidence, can do without. What happened can be put directly: a 737 Max 9 lost a fuselage panel at an altitude of 16,000 feet not long after departing Portland, OR, for Ontario, CA.

The panel is used instead of an exit door in some Max 9 configurations. As the BBC report explains, “The rear mid-cabin exit door is used in dense seating configurations on some Max 9 planes to meet evacuation requirements, but is ‘plugged’ on other planes, including the Alaska [Airlines] flight”. The carrier has taken 65 similar aircraft out of service.

Added to that number are the 79 Max 9s previously delivered to United Airlines. In total, 171 aircraft have been grounded following an FAA directive. The scale of disruption is hinted at by the Beeb also telling “Alaska said it cancelled 160 flights on Saturday, affecting about 23,000 passengers”. The “plugged” door area is held in place by four bolts. All must be inspected.

Fortunately, for those living on this side of the North Atlantic, “The European Union Aviation Safety Agency (EASA) is following the FAA approach, but flight disruptions on the continent are expected to be minimal. EASA said it believes no European airlines operate Max 9s with the configuration covered by the FAA order. One of the world's largest intercontinental airports, London Heathrow, said there was no impact on flights”. So how bad was the incident?

Potentially, very bad indeed: the panel blew out at just over 16,000 feet, with passengers still having their safety belts fastened. However, as the BBC report reminds us, “The cruising height of a 737 Max is around 38,000ft. At this level, the difference between the pressure inside the aircraft and the atmosphere outside is much greater. Had the door blown out here, the sudden rush of air would have been much more violent, and potentially lethal, especially if passengers were not wearing seatbelts”. And it gets worse still.

OH DEAR

A more recent Beeb report now tells “Alaska Airlines placed restrictions on the Boeing plane involved in a dramatic mid-air blowout after pressurisation warnings in the days before Friday's incident, investigators say”. Do go on.

“The jet had been prevented from making long-haul flights over water, said Jennifer Homendy of the US National Transportation Safety Board (NTSB) … Speaking at a news conference, Ms Homendy said pilots reported pressurisation warning lights on three previous flights made by the specific Alaska Airlines Max 9 involved in the incident”. There was more.

“The decision to restrict lengthy flights over water was so that the plane ‘could return very quickly to an airport’ in the event the warnings happened again, the NTSB chief added … ‘An additional maintenance look’ was requested but ‘not completed’ before the incident, Ms Homendy said”. Well, well.

Meanwhile, airlines that have committed to the 737 must be wondering what is going to happen next. A repeat of the Portland incident should be impossible for carriers like Ryanair, who thus far have restricted their new aircraft to the Max 8. But Michael O’Leary and his merry men have an order in for up to 150 Max 10s. Meanwhile, Airbus devotees are sitting pretty.

The problem for the Boeing 737 stems from the original design being rather too close to the ground for newer fan engines. Airbus could take a clean design brief with their A320 family. So the 737 had to have its engine intakes redesigned for the 300 to 800 series, with the infamous MCAS system for the Max. The company now needs to ensure it retains punters’ confidence after the Portland incident. Otherwise it could be in serious trouble.

Also, peak flying could be closer than the industry is prepared to admit.

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