AD 88-26-01 R2
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Robinson Helicopter Company | R22 | Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R22 Series Helicopters |
| aircraft | Robinson Helicopter Company | R22 ALPHA | Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R22 Series Helicopters |
| aircraft | Robinson Helicopter Company | R22 BETA | Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R22 Series Helicopters |
| aircraft | Robinson Helicopter Company | R22 MARINER | Airworthiness Directives; ROBINSON HELICOPTER COMPANY Model R22 Series Helicopters |
Unsafe Condition
Main rotor spindle failure due to cracks or surface defects exceeding 0.0005 inch depth, which could result in loss of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect main rotor spindle boltholes and adjacent surfaces using dye penetrant and visual inspection with 10X magnification. Shot peen and polish spindle surfaces per specified grits and intensity. Replace A106 journals with revised versions. Reinstall blades and track/balance rotor. Conduct repetitive inspections at intervals not exceeding 50 hours time in service for original spindles or 500 hours for reworked spindles.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Required prior to further flight for helicopters with spindles over 500 hours time in service or experiencing unexplained vibration increases. For spindles under 500 hours, comply before reaching 500 hours. Repetitive inspections required at intervals not exceeding 50 hours (original spindles) or 500 hours (reworked spindles) since last inspection.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Robinson Helicopter Company Model R22 series helicopters, all serial numbers with A158-1 main rotor spindle and A106 journals.
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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