One day before a Lion Air flight crashed in Indonesia late last year, killing all 189 on board, an off-duty pilot identified a malfunction on the plane and was able to fix it—the same malfunction thought to have caused the subsequent crash. Sources told Bloomberg the off-duty pilot happened to be sitting in the cockpit when the Boeing 737 Max 8’s flight-control system experienced a malfunction. The pilot reportedly knew how to fix the issue because the remedy was “part of a checklist that all pilots are required to memorize.” The next day, the same plane with a different crew reportedly faced the same malfunction—but crashed into the Java Sea. The presence of a third pilot was reportedly not included in Indonesia’s National Transportation Safety Committee’s November report about the crash. “All the data and information that we have on the flight and the aircraft have been submitted to the Indonesian NTSC,” Lion Air spokesman Danang Prihantoro told the news outlet. “We can’t provide additional comment at this stage due the ongoing investigation on the accident.” Boeing and Indonesia’s National Transportation Safety Committee reportedly declined to comment. Less than five months after the Indonesia plane crash, another Boeing 737 Max 8 crashed in Ethiopia, killing 57 people. The tragedy prompted several countries to ground the plane model and President Trump to declare an “emergency order” to stop its use by U.S. airlines.