The FAA has proposed requiring a series of software upgrades and other changes before the 737 MAX could return to service. The airplane has been grounded since March 2019 after two fatal crashes in five months killed 346 people.
“Robust transparency is needed to ensure that independent experts and the public can review whether this aircraft is truly safe before it takes to the skies again,” the senators wrote. Boeing and the FAA did not immediately comment
(Reporting by David Shepardson; Editing by Chizu Nomiyama)