The Boeing Company (NYSE:BA) continues to be plagued by problems with its 737 MAX jets, with deliveries being delayed due to a supply quality issue that might extend as far back as 2019.
According to a company statement, the issue affects a “significant” number of undelivered 737s and is likely to affect shipments in the short term.
Shares in Boeing dropped by 5% in London, halting a recent run that has seen its value climb by 60% over the past six months on increasingly bullish comments about 737 Max production and orders.
In New York, Boeing's shares were down nearly 6% in premarket trading.
Spirit AeroSystems, which supplies the fuselage parts concerned, had tumbled 14% before the opening bell in New York.
Boeing added the issue affects the MAX 7, MAX 8 and MAX 8200 aeroplanes as well as the P-8 Poseidon maritime surveillance aircraft but is not a safety of flight issue and in-service planes can continue to operate.
A statement from the US Federal Aviation Administration (FAA) also said there was no immediate safety issue "based on the facts and data Boeing presented" but added it will evaluate all affected aircraft before delivery.
The aeroplane maker said it was officially notified about the problem by Spirit on Wednesday and is still determining how many aircraft could be affected.
Boeing is ramping up 737 MAX production with 400 planes scheduled for delivery in 2023 in a plan that will see production rates rise to 38 a month in June from 31 currently.
--Updates for share price--