AD 2010-23-24

final rule
Data completeness: 70%

Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-70A and S-70C Helicopters

AD Number
2010-23-24
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2010-0490
FR Citation
75 FR 70101

Applicability

TypeManufacturerModelDetails
aircraft Sikorsky S-70A and S-70C Airworthiness Directives; Sikorsky Aircraft Corporation (Sikorsky) Model S-70A and S-70C Helicopters

Unsafe Condition

Crack in the tail gearbox output bevel gear (part number 70358-06620), which could lead to tail rotor separation, loss of tail rotor control, and subsequent loss of control of the helicopter.

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

Required Actions

Inspect the tail gearbox output bevel gear using Level II Ultrasonic Testing (UT) for cracks. If a crack is found, replace the gear with an airworthy one before further flight.

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

Compliance Time

Within 500 hours time-in-service (TIS), unless previously accomplished, and thereafter at intervals not exceeding 500 hours TIS.

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

Affected Aircraft

Sikorsky Aircraft Corporation Model S-70A and S-70C helicopters with a tail gearbox output bevel gear (part number 70358-06620), certificated in any category.

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

Source: Official FAA Source ↗

Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

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