AD 74-20-07 R5
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-61A | Airworthiness Directives; Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A, and S-61V Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A, and S-61V Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A, and S-61V Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61NM | Airworthiness Directives; Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A, and S-61V Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61R | Airworthiness Directives; Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A, and S-61V Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61V | Airworthiness Directives; Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A, and S-61V Helicopters |
Unsafe Condition
Fatigue cracks in the spar of a main rotor blade could lead to blade failure and subsequent loss of control.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove non-compliant main rotor blades within 10 hours time in service. Inspect blades with visual pressure indicators every 3 hours time in service or daily if inoperative. Install approved in-cockpit inspection systems or follow service bulletin procedures. Record inspections and restrict blades with unsafe indications.
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Compliance Time
within the next 10 hours time in service from the effective date
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Affected Aircraft
Sikorsky Models S-61L, S-61N, S-61NM, S-61R, S-61A (serial numbers 61083, 61087, 61094, 61161), and S-61V (serial number 61271) helicopters certificated in restricted or all categories.
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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