Boeing said it will be ‘carefully monitoring’ the aviation officials’ testimony, adding that ‘safety is our top priority.’ The FAA was ‘directly involved in the system safety review of the Manoeuvring Characteristics Augmentation System (MCAS),’ Elwell will tell lawmakers. ‘FAA engineers and flight test pilots were involved in the MCAS operational evaluation flight test,’ the remarks read. ‘The certification process was detailed and thorough, but, as is the case with newly certified products, time yields more data to be applied for continued analysis and improvement.’
However, Elwell is set to acknowledge that with increasingly complex systems, “our oversight approach needs to evolve to ensure that the FAA remains the global leader in achieving aviation safety.” The FAA is expected to defend its practices, including the delegation of key testing and certification to Boeing in light of tight government budgets, said Scott Hamilton, an aviation expert with Leeham Company. Lawmakers could push the FAA to pledge rigorous oversight before allowing the 737 MAX to return to service.
Preliminary results in the investigation into October 2018’s Lion Air crash in Indonesia indicate a single ‘angle of attack’ sensor, which feeds data to the MCAS, malfunctioned but continued transmitting data to the plane’s flight systems, including the MCAS. Among the changes to the system, the MCAS would automatically be disabled in cases where there is disagreement between two sensors. Boeing also intends to make standard on planes a ‘disagree light,’ to signal when the MCAS malfunctions. The feature currently is only available to airlines for an additional charge. The MCAS was installed in the MAX because the engines are heavier than in the previous versions of the 737.