AD 75-11-11

final rule
Data completeness: 70%

Airworthiness Directives; Sikorsky Models S-64E and S-64F Helicopters

AD Number
75-11-11
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Erickson Air-Crane S-64E Airworthiness Directives; Sikorsky Models S-64E and S-64F Helicopters
aircraft Erickson Air-Crane S-64F Airworthiness Directives; Sikorsky Models S-64E and S-64F Helicopters

Unsafe Condition

Failure of the torquemeter engine to gearbox shaft and gear assembly and consequent secondary damage to the main rotor control system components.

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

Required Actions

Remove torquemeter engine to gearbox shaft and gear assemblies with 3000 or more hours total time in service. Replace with P/N 6435-20564-042 assemblies having less than 3000 hours time in service, P/N 6435-20564-044 assemblies, or an equivalent approved by the FAA. Ensure replacement P/N 6435-20564-042 assemblies are removed before accumulating 3000 hours time in service.

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

Compliance Time

prior to further flight

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

Affected Aircraft

Sikorsky Models S-64E and S-64F helicopters with torquemeter engine to gearbox shaft and gear assemblies P/N 6435-20564-042

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

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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