Southwest Airlines pilot union said on Wednesday that extra computer-based training would be required as a result of a planned update to the software on the Boeing Co 737 Max, and it was seeking additional information for pilots.
Boeing has been working on a software update to an anti-stall system called MCAS since a Lion Air plane crashed in Indonesia in October.
That effort has become urgent after a second 737 Max 8 crashed in Ethiopia last week and regulators grounded the global fleet of the aircraft.