Boeing Confirms 737 MAX Software Changes, Defends Design


Image: USA Today

Following a rollout of new MCAS software over the weekend for pilots of five airlines operating the 737 MAX, Boeing on Wednesday brought together more than 200 stakeholders to formally discuss the changes and begin making the case for the aircraft to re-enter service.

As we’ve previously reported, the changes to the Maneuvering Characteristics Augmentation System will ensure that the system takes data from both angle-of-attack sensors, and that it applies corrective stabilizer trim only once, not repeatedly as originally configured. In addition, Boeing will prepare “computer-based” training that will take about an hour to complete. The company maintains that because the overall handling characteristics of the 737 MAX designs otherwise so closely mirror the predecessor 737s that no simulator training will be required.

At the press conference, Boeing defended the original design, saying that making the MCAS rely on one of two sensors (in effect, creating a single point of failure) was acceptable as long as recovery “can be quickly performed by a trained pilot using established procedures.”

The FAA will review the software changes when Boeing deems them complete, and there is not yet a formal timeline for this to happen.

In the meantime, the FAA’s acting administrator, Dan Elwell, is expected to testify in front of the Senate Commerce Committee today regarding the 737 MAX issues and FAA oversight of the certification process in place for the airliner. Earlier today, the FAA announced that it would audit the 737’s certification and issued this statement: “On March 19, 2019, Secretary of Transportation Elaine L. Chao requested that we initiate an audit to compile an objective and detailed factual history of the activities that resulted in the certification of the Boeing 737 MAX 8. We also received similar requests from several Members of Congress. Our audit objective will be to determine and evaluate FAA’s overall process for certifying the Boeing 737 MAX series of aircraft. In addition, we will identify and undertake future areas of work related to FAA’s actions in response to the crashes as needed.”