Safety Recommendation A-22-003

-From Bryan Bedofrd, Administrator: On February 13, 2025, the Federal Aviation Administration (FAA) published Airworthiness Directive (AD) 2025-02-11, Airworthiness Directives; FS 2001 Corp, FS 2002 Corporation, FS 2003 Corporation, Piper, and Piper Aircraft, Inc. Airplanes. This AD requires any rudder equipped with a rudder post to be replaced with a rudder equipped with a rudder post made from 4130N low-alloy steel on all applicable FS 2001 Corporation, FS 2002 Corporation, FS 2003 Corporation, Piper, and Piper Aircraft, Inc. airplane models. More information can be found on the Federal Register, Rules and Regulations, Volume 90, Issue 29, at the following web address:

https://www.govinfo.gov/content/pkg/FR-2025-02-13/pdf/2025-02528.pdf

I believe the FAA has effectively addressed the intent of Safety Recommendation A-22-3 and plans no further action on this safety recommendation.

On March 8, 2024, Administrator Witaker sent us a letter about FAA’s response to Safety Recommendation A-22-3, regarding Piper Aircraft Inc. rudders. The letter notifies the NTSB of the proposed AD, published in the Federal Register on October 6, 2023 (88 FR 69556).

We note that the NTSB was already aware of this AD, and provided comments to the public regulatory docket, available at Regulations.gov. In our comments, we told you the proposed AD was responsive to recommendation A-22-3. However, we also informed you that, following the publication of the proposed AD, Piper had provided information indicating that the PA-25 is likely affected by the issue described in the proposed AD. Based on this information, we urged you to include the PA-25, for which the type certificate is currently held by Latinoamericana de Aviación S.A., in the list of models to which the AD would apply. We hope this concern is addressed in the final AD.

As such, we consider our comments on the NPRM to be responsive to your March 8, 2024, letter and we do not plan to take any further action in response. We look forward to receiving an update once the AD is finalized.

-From Michael G. Whitaker, Administrator: The Federal Aviation Administration (FAA) continues to work with the design approval holders as they identify the appropriate corrective actions and generate service information to accomplish the corrective actions.

The FAA reviewed Piper Service Bulletin 1379, Rudder Inspection, dated December 2, 2022, which provides procedures for inspecting and replacing rudder posts made from American Iron and Steel Institute (AISI) 1025 carbon steel with AISI 4130N low-alloy steel. The service bulletin also allows for the replacement of the full rudder assembly with a new rudder made from AISI 4130N low-alloy steel.

Additionally, the FAA published an associated Notice of Proposed Rulemaking (NPRM) Airworthiness Directive (AD) to the Federal Register on October 6, 2023 (88 FR 69556). This NPRM AD proposes to require replacing any rudder equipped with a rudder post made from AISI 1025 carbon steel with a rudder equipped with a rudder post made from AISI 4130N low alloy steel on all applicable FS 2001 Corporation, FS 2002 Corporation, FS 2003 Corporation, Piper, and Piper Aircraft, Inc. airplane models.

The NPRM AD also references the Piper Service Bulletin 1379, which allows for testing of the rudder assembly to determine if the rudder assembly is made from AISI 4130N low alloy steel. We anticipate issuing the final AD by August 15, 2024.

I will keep the Board informed of the FAA’s progress on Safety Recommendation A-22-3 and anticipate providing an update by February 28, 2025.

The National Transportation Safety Board (NTSB) has reviewed the Federal Aviation Administration’s (FAA) notice of proposed rulemaking titled, “Airworthiness Directives; FS 2001 Corp, FS 2002 Corporation, FS 2003 Corporation, Piper, and Piper Aircraft, Inc. Airplanes,” which was published at 88 Federal Register 69556 on October 6, 2023. The notice proposes a new airworthiness directive (AD) applicable to certain FS 2001 Corp, FS 2002 Corporation, FS 2003 Corporation, Piper, and Piper Aircraft Inc. (Piper) airplanes.

The proposed AD was prompted by two accidents involving airplanes designed and built by Piper that sustained substantial damage when their rudder posts fractured above the upper hinge, causing the rudders’ top portion to fold over the upper tail brace wires, resulting in diminished control of the airplanes. We determined that the rudders were consistent with Piper part number 40622 and that the rudder posts were made of American Iron and Steel Institute (AISI) 1025 carbon steel, which likely fractured due to fatigue.

As a result, the NTSB issued Safety Recommendation A-22-3 asking the FAA to issue an AD that describes the safety risk associated with the continued use of Piper part number 40622 rudders equipped with a post made of AISI 1025 carbon steel and requires owners and operators to address the unsafe condition, such as by replacing them with rudders equipped with a post made of AISI 4130 low-alloy steel or its equivalent.

The proposed AD would require that any rudder equipped with a rudder post made from 1025 carbon steel be replaced with a rudder equipped with a rudder post made from 4130N low-alloy steel. The proposed AD would require Category I airplanes to comply within 2 years, Category II airplanes within 3 years, and all other airplanes within 5 years after the AD effective date. The NTSB is pleased that the FAA issued the proposed AD and encourages the FAA to expedite the final rule.

However, based on information received from Piper following the publication of this proposed AD, the NTSB urges the FAA to include the PA-25, for which the type certificate is currently held by Latinoamericana de Aviación S.A., in the list of models to which the AD would apply on the basis that the PA-25 is likely affected by the issue described in the proposed AD.

Thank you for the opportunity to comment.

We note that the FAA has determined that there is a safety risk associated with Piper part number 40622 rudder posts and plans to issue an AD to require owners and operators to take corrective action. Pending our review of the proposed AD, Safety Recommendation A-22-3 remains classified OPEN-- ACCEPTABLE RESPONSE.

-From Billy Nolen, Administrator, Federal Aviation Administration: The Federal Aviation Administration (FAA) initiated a safety investigation of the Piper part number 40622 rudder posts in accordance with our Continued Operational Safety process. The FAA determined that there is an associated safety risk and plans to issue a notice of proposed rulemaking to mandate corrective action through an airworthiness directive. We are working with design approval holders as they identify and generate service information to accomplish the appropriate corrective actions.

I will keep the Board informed of the FAA’s progress on Safety Recommendation A-22-3 and anticipate providing an update by December 31, 2023.

We note that you are reviewing our aviation investigation report and accident and inspection data that pertains to Piper part number 40622. We believe these are necessary first steps to taking the recommended action. Pending your completed review and the development of the recommended AD, Safety Recommendation A-22-3 is classified OPEN-- ACCEPTABLE RESPONSE.

-From Billy Nolen, Acting Administrator: The Federal Aviation Administration (FAA) is reviewing the findings from the Board’s report, “Structural Failure of Piper Part Number 40622 Rudder Posts Made of 1025 Carbon Steel,” along with material from the National Transportation Safety Board’s Aviation Accident Database that pertain to Piper part number 40622, including available safety inspection data. Our review will determine appropriate actions to address the associated safety risk if an unsafe condition exists.

I will keep the Board informed of the FAA’s progress on Safety Recommendation A-22-3 and anticipate providing an update by April 30, 2023.

The attached letter from the NTSB Chair provides information about the NTSB’s January 10, 2022, report Structural Failure of Piper Part Number 40622 Rudder Posts Made of 1025 Carbon Steel, NTSB/AIR-22/02. The details of this accident investigation and the resulting safety recommendations may be found in the attached report, which can also be accessed at http://www.ntsb.gov.

The NTSB is vitally interested in these recommendations because they are designed to prevent accidents and save lives. We would appreciate a response within 90 days of the date of this letter, detailing the actions you have taken or intend to take to implement these recommendations. When replying, please refer to the safety recommendations by number (A-22-3). We encourage you to submit your response to ExecutiveSecretariat@ntsb.gov. If your reply exceeds 20 megabytes, including attachments, please e mail us at the same address for instructions on how to send larger documents. Please do not submit both an electronic copy and a hard copy of the same response.

This letter provides information about the National Transportation Safety Board’s (NTSB) January 10, 2022, report Structural Failure of Piper Part Number 40622 Rudder Posts Made of 1025 Carbon Steel, NTSB/AIR-22/02. The details of the related accident investigations and the resulting safety recommendation may be found in the attached report, which can also be accessed at http://www.ntsb.gov.

As a result of findings in two investigations, we identified the following safety issue:

• The structural failure of Piper part number 40622 rudder posts made of American Iron and Steel Institute (AISI) 1025 carbon steel

Accordingly, the NTSB makes the following safety recommendation to the FAA.

• Issue an airworthiness directive that describes the safety risk associated with the continued use of Piper Aircraft Inc. part number 40622 rudders equipped with a post made of AISI 1025 carbon steel and that requires owners and operators to address the unsafe condition, such as by replacing them with rudders equipped with a post made of AISI 4130 low-alloy steel or its equivalent. The NTSB is vitally interested in this recommendation because it is designed to prevent accidents and save lives. We would appreciate a response within 90 days of the date of this letter, detailing the actions you have taken or intend to take to implement this recommendation.