AD 2021-05-19

final rule
Data completeness: 80%

Airworthiness Directives; Sikorsky Aircraft and Sikorsky Aircraft Corporation Helicopters

AD Number
2021-05-19
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2020-0920
FR Citation
86 FR 17283

Applicability

TypeManufacturerModelDetails
aircraft Sikorsky Aircraft and Sikorsky Airworthiness Directives; Sikorsky Aircraft and Sikorsky Aircraft Corporation Helicopters

Unsafe Condition

The manufacturer determined that there may be arm assemblies in service with 15,000 or more hours time-in-service (TIS), which exceeds the life limit for this component. This condition, if not addressed, could result in reduced or loss of tail rotor control and reduced control of the helicopter.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Review the mixer unit component log card or equivalent record to determine if the affected arm assembly is entered with the appropriate 15,000 hours TIS limit. If the limit has been exceeded, add the arm assembly entry and determine the remaining life. If the remaining life is less than 15,000 hours, replace the arm assembly.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 90 days after the effective date of this AD

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Sikorsky Aircraft Model S-61L, S-61N, S-61NM, and S-61R helicopters and Sikorsky Aircraft Corporation Model S-61A, S-61D, S-61E, and S-61V helicopters, certificated in any category including restricted, with an arm assembly part number S6140-62614-009, installed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 4, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.