Safety Recommendation Report: Assumptions Used in the Safety Assessment Process and the Effects of Multiple Alerts and Indications on Pilot Performance

​The National Transportation Safety Board (NTSB) is providing the following information to urge the Federal Aviation Administration (FAA) to take action on the safety recommendations in this report. They are derived from NTSB participation in the ongoing investigations of two fatal accidents under the provisions of Annex 13 of the International Civil Aviation Organization: the crash of Lion Air flight 610, a Boeing 737 MAX 8, PK-LQP, in the Java Sea shortly after takeoff from Soekarno-Hatta International Airport, Jakarta, Indonesia, October 29, 2018; and the crash of Ethiopian Airlines flight 302, a Boeing 737 MAX 8, Ethiopian registration ET-AVJ, near Ejere, Ethiopia, shortly after takeoff from Addis Ababa Bole International Airport, Ethiopia, March 10, 2019. As the accident investigation authority for the state of design and manufacture of the airplane in these accidents, the NTSB has been examining the US design certification process used to approve the original design of the Maneuvering Characteristics Augmentation System (MCAS) on the Boeing Company (Boeing) 737MAX. NTSB notes that, since the Lion Air accident on October 29, 2018, Boeing has developed an MCAS software update to provide additional layers of protection and is working on updated procedures and training. However, NTSB is concerned that the process used to evaluate the original design needs improvement because that process is still in use to certify current and future aircraft and system designs. Although the NTSB’s work in this area is ongoing, based on preliminary information, NTSB is concerned that the accident pilot responses to the unintended MCAS operation were not consistent with the underlying assumptions about pilot recognition and response that Boeing used, based on FAA guidance, for flight control system functional hazard assessments, including for MCAS, as part of the 737 MAX design. NTSB is making seven recommendations to address assumptions about pilot recognition and response to failure conditions used during the design certification process as well as diagnostic tools to improve the prioritization and clarity of failure indications presented to pilots.

• Record URL:
  https://www.ntsb.gov/investigations/AccidentReports/Reports/ASR1901.pdf
• 
• Summary URL:
  https://www.ntsb.gov/investigations/AccidentReports/Pages/ASR1901.aspx
• Corporate Authors:

  National Transportation Safety Board

  Washington, DC  United States 
• Publication Date: 2019-9-19

Language

• English

Media Info

• Media Type: Digital/other
• Features: References;
• Pagination: 13p

Subject/Index Terms

• TRT Terms: Air pilots; Aviation safety; Behavior; Certification; Crash analysis; Crash investigation; Fatalities; Flight control systems; Recommendations; Software; Warning signals
• Identifier Terms: Boeing 737 MAX aircraft; U.S. Federal Aviation Administration
• Geographic Terms: Ejere (Ethiopia); Jakarta (Indonesia)
• Subject Areas: Aviation; Safety and Human Factors; Vehicles and Equipment;

Filing Info

• Accession Number: 01720375
• Record Type: Publication
• Report/Paper Numbers: ASR-19-01, Accident ID: DCA19RA017; DCA19RA101
• Files: TRIS
• Created Date: Oct 28 2019 10:26AM