A new statement released from Boeing reveals they knew the Max 737 planes had an issue with one of the safety features but did nothing.  

The statement released on Sunday; Boeing says they were made aware of the issues within months of delivering the first 737 Max planes to airlines. The indicator, also called the angle of attack to disagree alert is designed to warn the pilots if the plane’s sensor is transmitting contrasting data about the direction of the plane’s nose.  

“In 2017, within several months after beginning 737 MAX deliveries, engineers at Boeing identified that the 737 MAX display system software did not correctly meet the AOA Disagree alert requirements,” Boeing said. “When the discrepancy between the requirements and the software was identified, Boeing followed its standard process for determining the appropriate resolution of such issues. That review, which involved multiple company subject matter experts, determined that the absence of the AOA Disagree alert did not adversely impact airplane safety or operation.” 

The AOA disagree alert only functioned if the airline had purchased the AOA indicator, an additional feature, Boeing said. The AOA indicator alerts the pilots if the AOA sensor is not working: the disagree alert shows if the sensors dispute each other.  

While it isn’t known if the presence of the alert function could’ve been a part of the Lion Air and Ethiopian Airlines plane crashes, what is known is that it could’ve alerted the pilots that the plane’s sensor was faulty.