When 737 malfunctions, the pilot will first see a general MASTER CAUTION light illuminate at the top of the instrument panel. A 2019 NASA report by Randy Mumaw, a human factors specialist who worked for Boeing, analyzed eighteen accidents (a third involving 737 variants) and identified warning system failures in all of them. Inadequacies in warning systems that cause – or contribute to – confusion or inaction at a critical time are a frequent factor in accidents. It must also «provide a means to suppress an attention component of an alert that interferes with the flight crew’s ability to safely operate the airplane». Among others, it must be «readily and quickly detectable and intelligible to the flight crew in all foreseeable operational situations, including those in which multiple alerts are provided». Chapter 25.1322-1 deals with the specific requirements it must meet. The certification requirements for crew warning systems are outlined in Title 14-part 25 Transport Category Aircraft. After the end of the current year, only aircraft that comply with the updated requirements can be certified.ĭuring the original MAX certification, Boeing persuaded the FAA to exempt the aircraft from the regulations on the grounds that any safety benefits would not be «commensurate with the costs». This clause will allow non-compliant aircraft to be certified until the end of the current year.