The pilots of one of two doomed Boeing 737 Max jets likely had just 40 seconds to override an automated system and avert disaster, The New York Times reported as the U.S. Department of Transportation announced new watchdog efforts to improve aviation safety.

According to flight simulation tests reviewed by the Times that re-created the Lion Air planes fatal crash, a single sensor failed during the October flight. This triggered an automated system that was designed to help prevent a stall but instead sent the plane into a nosedive.

The pilots would have had less than a minute to disengage the system. During the flights final moments, however, cockpit voice recordings captured the planes pilots flipping through a technical manual in an attempt to understand what was happening, as Reuters previously reported.