Boeing handed over to the US Federal Aviation Administration 17 October instant messages between two Boeing pilots in which one expresses serious concern with the 737 Max's Maneuvering Characteristics Augmentation System (MCAS).
Reuters broke the story 18 October, followed by a report in The New York Times.
The Times and Reuters report that in 2016 the 737 Max's chief technical pilot at the time sent messages to another Boeing pilot that the MCAS is "running rampant in the sim" – referring to the flight simulator – and that the system's performance was "egregious".
The MCAS has been implicated in the fatal crash of two 737 Max's, which led to the grounding of the fleet in March.
The Times reports that eight months before sending the messages, the 737 Max's chief technical pilot had asked the FAA to avoid mentioning the MCAS in the aircraft's pilot's manual. The FAA complied with this request.
Boeing has confirmed with the FAA that it discovered the messages "some months" ago.
FAA states 18 October that the previous day Boeing alerted the Department of Transportation to the existence of the instant messages, "characterizing certain communications with the FAA during the original certification of the 737 Max in 2016". The DOT immediately alerted FAA leadership.
"The FAA finds the substance of the document concerning," the FAA states. "The FAA is also disappointed that Boeing did not bring this document to our attention immediately upon its discovery. The FAA is reviewing this information to determine what action is appropriate."
The FAA has shared the messages with Congressional lawmakers.
US Congressional representative Peter DeFazio (D-OR), who chairs the House Committee on Transportation and Infrastructure, which is investigating the circumstances surrounding the grounding of the 737 Max, states that the revelation of the Boeing pilot's 2016 messages are "not about one employee; this is about a failure of a safety culture at Boeing in which undue pressure is placed on employees to meet deadlines and ensure profitability at the expense of safety".
DeFazio warns Boeing that it will have to "answer for this" at the committee's 30 October hearing.
The Southwest Airlines Pilots Union (SWAPA), which has filed a lawsuit against Boeing seeking damages for pilots represented by the union who have lost compensation since the grounding of Max aircraft, says the FAA's 18 October statement presents "more evidence that Boeing misled pilots, government regulators and other aviation experts about the safety of the 737 Max".