In the five years since two Boeing 737 MAX crashes left hundreds of people devastated throughout the world, the families who lost loved ones have quietly fought a legal war against the aircraft maker.

According to The Seattle, Times,bBoth crashes, which killed 189 people in Indonesia in October 2018 and 157 people in Ethiopia four months later, were caused by defective flight control software on the then-new plane.

Boeing 737 MAX Accidents Victims' Families Fight for Justice

All but 41 of the hundreds of cases filed against Boeing have already been settled, as the company sought to move on from the calamity that soiled its brand and shattered its balance sheet.

While Boeing has publicly defended its quality control methods and dedication to safety in the aftermath of the fatal MAX accidents, its attorneys worked behind closed doors to reach a settlement with the relatives of those killed.

The remaining cases are being heard as Boeing faces a new round of lawsuits from passengers who blame the company for a safety incident involving its MAX planes, a near-disaster that reignited scrutiny of Boeing that had waned in the years since the tragedies in Jakarta and Addis Abeba.

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Boeing Whistleblower Alleges 'Criminal Coverup'

Meanwhile, a Boeing whistleblower claims there is a "criminal coverup" surrounding January's Alaska Airlines disaster.

Ed Pierson was one of four witnesses who spoke Wednesday before the Senate's Permanent Subcommittee on Investigations. Pierson was a senior manager at Boeing's 737 manufacture who retired in 2018, before the first Max 8 tragedy.

He has repeatedly expressed concerns about the narrowbody jet's safety, and claims that he once got off a 737 Max before it took off because he realized the plane model he had boarded.

Pierson's testimony on Wednesday contained a crucial new claim about the Alaska Airlines accident inquiry. "I'm not gonna sugarcoat this, this is a criminal coverup," he went on to say.

After a 737 Max 9 lost its door plug in midair, exposing a gaping hole in the fuselage, the National Transportation Safety Board reported that critical bolts designed to lock it were missing.

The NTSB stated that the door plug was removed in Boeing's factory to repair some broken rivets, but the company told investigators that it did not have record of this work.

The Seattle Times said that Pierson was referring to the shipside action tracker, an informal database used to document problems at the 737 Max manufacturing.

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