Starting mid-April, the aircraft manufacturer will reduce output from 52 aircraft to 42 per month.
Boeing says the move will allow it to focus resources on further addressing software fixes for the aircraft following two fatal crashes in just five months.
Last October, Lion Air flight 610 crashed into the Java Sea shortly after taking off from Jakarta, killing all 189 people on board.
Then in March, Ethiopian Airlines flight 302 crashed en route to Nairobi. All 157 people on board died. Both flights were operated by Boeing 737 MAX aircraft.
Preliminary investigations have highlighted similarities between the two tragedies, most notably around the role played by the 737 MAX’s manoeuvering characteristics augmentation system (MCAS).
Crash investigators have been focusing their attentions on the MCAS, which is designed to automatically correct the angle at which the aircraft is flying if it becomes too steep.
A preliminary report on the Lion Air crash found an “erroneous” sensor input feeding the MCAS caused the aircraft to nose-dive.
Ethiopia’s transport minister Dagmawit Moges, meanwhile, said its aircraft suffered “repetitive uncommanded aircraft nose down conditions”.
Boeing chief executive Dennis Muilenburg said on Friday (April 5): “We now know the recent Lion Air flight 610 and Ethiopian Airlines flight 302 accidents were caused by a chain of events, with a common chain link being erroneous activation of the aircraft’s MCAS function.
“We have the responsibility to eliminate this risk, and we know how to do it. As part of this effort, we’re making progress on the 737 MAX software update that will prevent accidents like these from ever happening again.
“Teams are working tirelessly, advancing and testing the software, conducting non-advocate reviews, and engaging regulators and customers worldwide as we proceed to final certification.”
Boeing is also working on new pilot training courses and documentation for the 737 MAX.
Muilenberg, though, stressed Boeing would “take the time necessary” to ensure the fix is effective.
Estimates for when the 737 MAX will re-enter service vary significantly, but it is broadly accepted July is likely to be the earliest 737 MAX operations could resume.
Others, like Tui, have adjusted their operations with a longer grounding in mind, so far forward as late September.
Muilenburg said the adjustments to Boeing’s production schedule would allow it to “prioritise additional resources to focus on software certification”.
