US lawmakers say aviation giant Boeing discovered in 2017 that a cockpit warning light on its 737 MAX aircrafts that played a role in two air disasters was defective but decided to defer fixing it until 2020.
US Representatives Peter DeFazio of Oregon and Rick Larsen of Washington state said in a statement on Friday that Boeing sped up the process of fixing the defect only after the first of two deadly crashes involving Max planes last October in Indonesia.
The feature, called an angle of attack alert light, was designed to warn pilots when sensors measuring the direction of the planeís nose up or down relative to oncoming air might not be working.
The faulty sensor and warning light is suspected of playing a role in two deadly crashes involving Boeing’s best-selling 737 MAX in Indonesia in October and in Ethiopia in March, killing 346 people.
The sensors fed incorrect information to computers on board the two planes.
DeFazio and Larsen said Boeing decided in November 2017 to defer a software update to correct the so-called AOA Disagree alert defect until 2020, three years after discovering the flaw.
The two legislators, both leaders of a House of Representative committee thatís investigating the Max crashes, said Boeing did not inform the US Federal Aviation Administration (FAA) about the defect until after the Lion Air crash more than one year later, the lawmakers said.
Larsen questioned why Boeing didnít consider the problem critical to safety "and I am concerned it took Boeing so long to report this defective feature to the FAA and its customers."
The two 737 MAX crashes have left Boeing facing one of the biggest crises in its more than 100-year history and have triggered investigations by the US government and members of Congress.
The planes have been grounded around the world since March, awaiting approval from US and international regulators before they can return to service.