The USA’s National Transportation Safety Board has issued seven recommendations about the design of alerts and indicators in cockpits and how they are assessed for safety as a result of the ongoing investigation into the Boeing 737 Max accidents.
The National Transportation Safety Board’s (NTSB) recommendations relate to how the Federal Aviation Administration (FAA) assesses the design of cockpit alerts and indicators. In particular they highlight how multiple alerts and indications are considered when making assumptions as part of design safety assessments.
The US-safety board is supporting Indonesia’s Komite Nasional Keselamatan Transportasi (KNKT) investigation of the October 29, 2018, crash of Lion Air flight 610 in the Java Sea and the Aircraft Accident Investigation Bureau of Ethiopia’s investigation of the crash of Ethiopian Airlines flight 302 near Ejere, Ethiopia.
All passengers and crew on board both aircraft – 346 people in all – died in the accidents. Both crashes involved a Boeing 737 MAX airplane.
NTSB chairman Robert Sumwalt said, “We saw in these two accidents that the crews did not react in the ways Boeing and the FAA assumed they would.
“Those assumptions were used in the design of the airplane and we have found a gap between the assumptions used to certify the MAX and the real-world experiences of these crews, where pilots were faced with multiple alarms and alerts at the same time.
“It is important to note that our safety recommendation report addresses that issue and does not analyze the actions of the pilots involved in the Lion Air and Ethiopian Airlines accidents. That analysis is part of the ongoing accident investigations by the respective authorities.”
The NTSB has recommended that system safety assessments should consider the effects of alerts on pilot responses and address gaps in design, procedures and training and that robust tools and methods for validating assumptions about pilot responses to airplane failures should be made as part of design certification.
System diagnostic tools to improve the prioritization of and more clearly present failure indicators should also be developed to improve the timeliness and effectiveness of a pilot’s response.
The NTSB said it has finished examining the safety assessments conducted as part of the original design process for the Maneuvering Characteristics Augmentation System on the 737 MAX being blamed for the accidents. It has issued the recommendations “out of its concern that the process needs improvement given its ongoing use in certifying current and future aircraft and system designs”, it added.
The KNKT’s accident report is expected to be released in the coming months.