The Federal Aviation Administration has found a potential risk in the Boeing 737 Max software update that was supposed to improve safety after the jets were grounded worldwide following two fatal crashes since October.
Investigators found a problem with the updated Maneuvering Characteristics Augmentation System, or MCAS, automated flight control system, during a flight simulation. If the MCAS software senses the plane is going into a stall, the system pushes the plane’s nose down repeatedly, which is a standard procedure to avoid a stall. Investigators believe the MCAS system may have been responsible for the two deadly crashes.
Pilots testing the MCAS update in a simulator, however, found that it took them too long to recover the airplane if the software was trying to avoid a stall, a source close to the investigation told NBC News.
The FAA said in a statement to NBC News that its job is to find potential problems and that it found “a potential risk that Boeing must mitigate.”
“The FAA will lift the aircraft’s prohibition order when we deem it is safe to do so,” the statement said. “We continue to evaluate Boeing’s software modification to the MCAS and we are still developing necessary training requirements.”
Boeing has traced the issue to a microprocessor and how the chip handles data, but believes it can address the issue with a software code update.