FAA mandate of research of similar design
Tillaga í öryggisátt
The Icelandic Transportation Safety Board (ITSB) recommends to the FAA, to research the need for making inspections, and possible replacement, of spoiler actuator’s Blocking and Thermal Relief Valve Housing mandatory via issue of airworthiness directive, for other large transport category aircraft with similar spoiler actuator design.
Afgreiðsla
The FAA has issued Safety Recommendation 15.116, gathering and reviewing compliance data, including hazard assessments, for each type of Title 14, Code of Federal Regulations (14 CFR) Part 25 airplane operating under part 121. The FAA will be addressing Safety Recommendation 15.116 for U.S.-manufactured aircraft. Furthermore, the FAA recommended to the ITSB to provide a similar recommendation to foreign aviation authorities for each State of design. The board of ITSB approved on a board meeting held on January 15th, 2016, to contact other states of designs of aircraft of similar spoiler design and extend the recommendation as needed.
Update: 31.01.2017:
The FAA has reviewed the design, manufacturing, and service information and determined the Boeing Model 757 failed BTRV housing was under-designed in that it had insufficient fatigue life. The reason for this was found to be a design error that led to a premature failure. The valve itself was designed by a third party, Moog, which reported that the valve is used only on the Boeing Model 757 series airplanes. Therefore this under-designed part is not on any other transport airplanes. Additionally, a quary of the FAA Service Difficulty Report (SDR) database did not reveal any other spoiler issue associated with the blocking/thermal relief valves in the past fifteen years on any transport airplanes. The FAA considers its action to Safety Recommendation 15.116 completed.