NTSB · Safety Recommendation
Safety Recommendation A-06-038
Recommendation
TO THE FEDERAL AVIATION ADMINISTRATION: Adopt Society of Automotive Engineers ARP5150 into 14 Code of Federal Regulations Parts 21, 25, 33, and 121 to require a program for the monitoring and ongoing assessment of safety-critical systems throughout the life cycle of the airplane. Safety-critical systems will be identified as a result of A-06-36. Once in place, use this program to validate that the underlying assumptions made during design and type certification about safety-critical systems are consistent with operational experience, lessons learned, and new knowledge.
Safety Issue and Context
Certification of systems that are critical to safety of flight has been an issue in several National Transportation Safety Board accident investigations of transport-category airplanes. In 1999, the Safety Board expressed concern about the Federal Aviation Administration's (FAA) certification process during its investigation of the rudder actuator in USAir flight 427. In 2000, the Board suggested the need for a directed examination of the certification process in the investigation of the center wing fuel tank in TWA flight 800.
Subsequent investigations of the horizontal stabilizer jackscrew in Alaska Airlines flight 26 1 and the rudder system in American Airlines flight 5874 also raised questions about the certification process used by the FAA to determine compliance with airworthiness standards. These four accidents resulted in 715 fatalities and accounted for 60 percent of the air carrier fatalities that occurred from 1994-2001 . In each of these accidents, the Board identified a safety-critical system that suffered a catastrophic failure, and issued certification-related recommendations to address system-specific design, operational, or maintenance issue.
Response History
December 9, 2014 · NTSB Correspondence · FAA
We are pleased that, in response to this recommendation, you developed the monitor safety analyze data (MSAD) Order, which you published on March 12, 2010, and which became effective on January 31, 2011. The MSAD Order describes the processes and procedures that you will use to identify and analyze the data necessary for effective continued operational safety oversight. On November 4, 2011, you issued FAA Policy Statement, PS-ANM-25-05, “Risk Assessment Methodology for Transport Category Airplanes,” which describes how you evaluate the fleet risk for both systems and structures.
The issuance of these documents and implementation of the practices they describe satisfies Safety Recommendation A 06 38, which is classified CLOSED—ACCEPTABLE ACTION.
October 28, 2013 · Recipient Response · FAA
-From Michael P. Huerta, Administrator: As mentioned in previous correspondence, Monitor Safety Analyze Data (MSAD) is the overarching process by which we will monitor and assess the safety critical systems identified as a result of implementing Safety Recommendation A-06-36. MSAD works in coordination with processes and programs to monitor the operational fleet. MSAD provides continued operational safety (COS) management guidance that applies the principles of SAE ARP5150 to airplane systems and structures. It ensures informed decision making by requiring a structured risk analysis process for potential safety issues and effective corrective actions through the use of root cause analysis.
Since our previous letter, the FAA has made progress on COS risk assessment guidelines and processes supporting MSAD, including:
• FAA Policy Statement: PS-ANM-25-05, Risk Assessment Methodology for Transport Category Airplanes, which evaluates the fleet risk for both systems and structures. We issued the policy statement on November 4, 20 11 , and it can be found at the following Web site: http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgPol