A newly discovered issue with the 737 MAX could force the manufacturer to rework hundreds of aircraft of the type and potentially suspend new deliveries of the 737 MAX for a time.
The issue was discovered by Spirit AeroSystems, which notified Boeing about a problem that a “non-standard manufacturing process” was used when joining the aft fuselage and the vertical tail with two fittings of certain 737 MAX-7, MAX-8, MAX-8-200, and the P-8 Poseidon, which is based on the 737 NextGeneration (NG). The 737 MAX-9 is not affected.
Bloomberg first reported the issue on April 13, 2023.
Spirit AeroSystems is a Tier 1 supplier, building and delivering the fuselages of the 737, as well as other Boeing aircraft such as the 767, 777/777X, and 787. The Wichita, Kansa, the United States (US)-based also supplies parts to several Airbus programs, including the A220, the A320ceo/neo family, and A350. Previously, it supplied components to the Boeing 747-8 and Airbus A380, neither of which is still being manufactured.
Four-year production span
According to the supplier, the problem could affect Boeing 737 MAXs that were built over the past four years, including those that were produced following the groundings of the type in March 2019.
Aviation authorities grounded the aircraft following its second fatal crash in a span of a few months, as an Ethiopian Airlines Boeing 737 MAX plunged to the ground shortly after take-off from Addis Ababa Bole International Airport (ADD), Addis Ababa, Ethiopia.
While it is not “an immediate safety of flight issue,” allowing the currently active 737 MAXs to continue flying, it will “affect a significant number of undelivered 737 MAX airplanes, both in production and in storage,” according to a statement by Boeing.
The manufacturer temporarily suspended the production of the 737 MAX between January 2020 and May 2020, as authorities did not unground the aircraft during 2019.
According to ch-aviation.com data, the US-based Original Equipment Manufacturer (OEM) built 879 Boeing 737 MAX (excluding the MAX-9) between January 1, 2019, and April 14, 2023. Meanwhile, Boeing built 438 aircraft of the type (excluding 737 MAX-9) between November 1, 2020, and April 14, 2023, ch-aviation.com reports. The US Federal Aviation Administration (FAA) ungrounded the 737 MAX on November 18, 2020, with American Airlines operating the first post-grounding flight with the type on December 29, 2020.
In terms of deliveries, Boeing handed over 752 aircraft of the type (excluding 737 MAX-9) between November 18, 2020, and April 14, 2023, ch-aviation.com data shows.
Boeing is currently evaluating the full scale of the problem – whether deliveries will have to be suspended and whether 737 MAXs actively flying with airlines need to be looked at.
Pausing deliveries of other aircraft
If Boeing were to suspend some or all deliveries of the 737 MAX, it would be the third time this year that the manufacturer had stopped handing over aircraft.
Firstly, Boeing suspended the deliveries of the 767F and the military derivative of the 767, the KC-46A, due to a problem related to the center wing fuel tank, whereby the fuel tanks were not properly cleaned and primed prior to delivery. As a result, with fuel filters potentially becoming clogged due to this issue, the manufacturer did not deliver a single 767F between December 2022 and March 2023. Boeing finally handed over a 767F to FedEx Express on April 4, 2023.
Secondly, the Original Equipment Manufacturer (OEM) briefly paused deliveries of the 787, as an “analysis error by our supplier related to the 787 forward pressure bulkhead” resulted in no Dreamliners being delivered between February 23, 2023, and March 15, 2023, when Lufthansa received a 787-9, registered as D-ABPC.