There have already been signs that the 737 Max's fatal safety flaw may have stemmed from misunderstandings, and now investigators appear to have more tangible evidence of this. Boeing has confirmed to Reuters that it gave the FAA instant messages indicating that pilots may have misled regulators about the performance of the MCAS anti-stall technology linked to two deadly crashes. The company's then-serving chief technical pilot told another pilot that he had "basically lied" to the FAA about MCAS during the 737 Max's certification process, albeit "unknowingly." That's consistent with earlier New York Times claims that the chief technical pilot didn't fully understand the system.
The FAA confirmed receiving notice about the messages, noting that Boeing had discovered them "some months ago." While it didn't discuss the specific content of the messages, it said they were "concerning" and was reviewing the chats to decide what came next.
Boeing is in the midst of fixing the flaw, in part by requiring that the anti-stall system rely on both flight control computers for aircraft data instead of one. However, it's still less than clear as to how the company got to that point. The messages may help fill in an important blank and help Boeing fix any institutional failings that may have let MCAS slip through the cracks.