NTSB · Safety Recommendation
Safety Recommendation A-21-046
Recommendation
TO THE FEDERAL AVIATION ADMINISTRATION: Identify all currently certificated transport-category airplanes for which system safety assessments for landing gear systems did not consider human error that could lead to cross-wiring of antiskid brake system components, including the wheel speed transducers, and require manufacturers of transport-category airplanes without such assessments to perform the assessments and then implement mitigations to prevent cross-wiring of antiskid brake system components.
Safety Issue and Context
This report discusses the October 17, 2019, accident involving a Saab SA-2000 airplane, operated by Peninsula Aviation Services Inc. d.b.a. PenAir flight 3296, which overran the end of runway 13 at Unalaska Airport, Unalaska, Alaska. The airplane was substantially damaged during the runway overrun; as a result, of the 3 crewmembers and 39 passengers aboard, 1 passenger sustained fatal injuries, and 1 passenger sustained serious injuries. Eight passengers sustained minor injuries, most of which occurred during the evacuation.
Safety issues identified in this report include the potential for cross-wiring of airplane antiskid brake systems; insufficient Federal Aviation Administration (FAA) guidance to identify safety risks for air carriers experiencing significant organizational changes, including bankruptcy, acquisition, and merger; lack of FAA consideration of runway safety area dimensions during the process of authorizing an air carrier to operate its aircraft at a specific Title 14 Code of Federal Regulations Part 139 certificated airport, and the benefits of safety management systems for design, manufacturing, and maintenance organizations.
As a result of this investigation, the National Transportation Safety Board makes six new safety recommendations to the FAA, three new safety recommendations to the European Union Aviation Safety Agency, and one new recommendation to the Saab Group.
Response History
August 7, 2026 · Recipient Response · FAA
-From Bryan Bedford, Administrator: On February 26, 2025, the Board requested that the Federal Aviation Administration (FAA) provide the method that each applicant used to demonstrate compliance with Title 14, Code of Federal Regulations (14 CFR) 25.1309. Both the design approval holders (DAHs) and the methods of compliance (MOCs) are identified in the attachment provided.
Furthermore, we have completed our assessment of FAA-approved type designs for transport category airplanes relevant to the landing gear brake system components, including the antiskid system. We determined that the approved type designs are compliant with all relevant regulatory requirements. The DAHs'’ MOC included the use of design criteria, installation testing, and maintenance procedures, as well as a system safety assessment for certain designs. The MOCs identified have been found to satisfy the requirements of 14 CFR 25.1309 and associated guidance for system design and assessment. No additional showing of compliance has been determined to be necessary at this time.
The FAA issues airworthiness directives (AD) when an unsafe condition exists in a product and is likely to exist or develop in other products of the same type design. When an AD is issued to address an unsafe condition, 14 CFR 21.99 requires DAHs to submit design changes for approval to correct the unsafe condition. Our review of the approved type design for aircraft brake systems, including antiskid components, has not identified an unsafe condition, and we do not have a foundation to require the DAHs to submit design changes or conduct an additional review of FAA-approved data. Doing so would constitute a request for showing compliance, which would be outside of FAA’s current policy.
I believe the FAA has effectively addressed this safety recommendation and consider our actions complete.