Years before two Boeing 737 Max jets crashed in Indonesia and Ethiopia, U.S. regulators found a pattern of recurring safety problems with the manufacturing giant.

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As Boeing faces intense scrutiny over back-to-back crashes of its 737 Max jet, documents and interviews show that the company had safety problems known to federal regulators for years.

In 2015, the FAA decided to try to get Boeing to meet, then go beyond, federal safety requirements by addressing broader corporate culture and governance issues, including what agency officials considered a lack of transparency.'

The week before Christmas of that year, Boeing and the FAA signed a five-year settlement agreement that was unprecedented in scope. The company paid a modest $12 million penalty, but it agreed to make significant changes in its internal safety systems and practices for “ensuring compliance” with regulations.

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But over the first 3½ years of the agreement, Boeing failed to meet some of its obligations, according to two people who requested anonymity to discuss details of the settlement.

Boeing says it has taken major steps to comply. The FAA, meanwhile, last year chose not to invoke enforcement provisions that could have meant $12 million in additional penalties for the company. The agreement runs through Dec. 31, 2020, and there is the potential for more financial penalties if Boeing fails to meet the requirements.

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Boeing’s inability to rid its newly built planes of what it calls “Foreign Object Debris,” such as tools left behind, was one of the problems that prompted the settlement. But an FAA official said the company is still struggling with the issue, and a top Air Force official told Congress the government temporarily halted deliveries of Boeing tankers earlier this year over “FOD” problems.

The company committed to improving the quality and timeliness of information it provides to the FAA. But in the case of the 737 Max, the FAA said, it took Boeing more than a year to notify it about a software problem that disabled a crucial warning light connected to the automated system at the center of the tragedies.

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In 2008, the FAA gave Boeing and other companies more than two years to provide airlines with the technical information they needed to comply with a post-TWA regulation intended to make fuel tanks less flammable.

Boeing missed the deadline by more than 300 days, and the FAA took legal action in response to Boeing’s “tardiness.”

Critics say that because of the firm’s importance to the U.S. economy, its confidence in its own technical expertise and its deep ties in Washington, Boeing has a history of shaping the rules it follows — and slow-rolling legal mandates it doesn’t consider a priority.

The European Aviation Safety Agency (EASA) has presented Boeing with five major requirements that need to be addressed, before the 737 MAX returns to service.
Reported by Bloomberg on the 6th of July 2019, the article notes the aircraft will not be allowed to fly again until the requirements are addressed and are tested accordingly.

The five requirements the European Aviation Safety Agency have listed so far are as follows:

• Reduce the difficulty manually turning the trim wheel
• Address the unreliability of Angle of Attack sensors
• Address the training situation
• Investigate software issues with a lagging microprocessor