Boeing acknowledges flaw in 737 MAXs

Boeing acknowledged it had to correct flaws in its 737 MAX flight simulator software used to train pilots, after two deadly crashes involving the aircraft that killed 346 people.

The company said in a statement had it corrected the software and "provided additional information to device operators to ensure that the simulator experience is representative across different flight conditions."

Its statement marked the first time Boeing acknowledged there was a design flaw in software linked to the 737 MAX, whose MCAS anti-stall software has been blamed in large part for the Ethiopian Airlines tragedy. According to Boeing, the flight simulator software was incapable of reproducing certain flight conditions similar to those at the time of the Ethiopian Airlines crash in March or the Lion Air crash in October.

In March, a 737 MAX crashed in Ethiopia, killing all 157 on board. Another 737 MAX crashed in Indonesia in October, killing 189 people. Multiple aviation authorities grounded Boeing 737 MAX 8 and MAX 9 aircraft after the second crash.

Boeing said Thursday that it completed its software update on the 737 MAX. The proposed fix, which addresses a problem with a flight handling system thought to be a factor in both crashes, must now win approval from U.S. and international regulators before the planes can return to service. U.S. airlines have targeted August as the date they expect to resume flying on the 737 MAX.