The Federal Aviation Administration plans to hold a meeting on Friday with representatives from U.S. airlines and pilot unions to discuss the ongoing grounding of the 737 Max, the agency confirmed. Meant to “further inform [the FAA’s] ongoing review,” the meeting will involve the three airlines that fly the Max—Southwest Airlines, United Airlines, and American Airlines—and leaders from the Air Line Pilots Association, the Allied Pilots Association, and the Southwest Airlines Pilots Association.
“The purpose of this meeting is for the FAA to gather facts, information, and individual views to further understand their views as FAA decides what needs to be done before returning the aircraft to service,” said the agency in a statement.
The grounding has disrupted schedules at all three airlines. United and American Airlines have canceled flights through early June while Southwest has canceled flights until the end of May as a result.
The last major aviation authority to ground the model following the March 10 crash of an Ethiopian Airlines Max 8 that killed all 157 aboard, the FAA now leads a review of Boeing’s 737 Max software and flight deck updates initiated last November following the crash of a Lion Air Max 8 that killed 189.
The updates center on the Max’s maneuvering characteristics augmentation system (MCAS) and related systems and equipment. One of the principal changes involves the angle-of-attack (AOA) sensors, inputs from both of which the MCAS will now compare. If the sensors disagree by 5.5 degrees or more with the flaps retracted, the MCAS will not activate. An indicator on the flight deck display will alert the pilots.
In the previous design, certified by the FAA under an amended type certificate, a fault in a single angle of attack sensor could trigger the MCAS to send the airplane into an uncommanded nose-down attitude. Investigators believe both Max 8 crashes happened under similar circumstances and involved repeated automatic MCAS commands.
In the new design, if the MCAS activates in non-normal conditions, it will provide just one input for each indication of an AOA problem. Finally, the MCAS can never command more stabilizer input than the pilots can counteract by pulling back on the control column, meaning the pilots can at all times override the MCAS and manually control the airplane.
Boeing also has updated the Max’s computer-based differences training and manual review on the MCAS function, associated existing crew procedures, and related software changes.