Airworthiness Directive · Amendment 39-17502 · Main rotor head
Various Restricted Category Helicopters
This AD applies to Arrow Falcon Exporters Inc.; AST, Inc.; Bell Helicopter Textron, Inc.; Global Helicopter Technology, Inc.; Hagglund Helicopters, LLC; JJASPP Engineering Services, LLC; Northwest Rotorcraft, LLC; Overseas Aircraft Support, Inc.; Richards Heavylift Helo, Inc.; Robinson Air Crane, Inc.; Rotorcraft Development Corporation; San Joaquin Helicopters; Southern Helicopter, Inc.; and Tamarack Helicopters, Inc. Model HH-1K, TH-1F, TH-1L, UH-1A, UH-1B, UH-1E, UH-1F, UH-1H, UH-1L, and UH-1P helicopters, and Southwest Florida Aviation International, Inc., Model UH-1B (SW204 and SW204HP) and UH-1H (SW205) helicopters, certificated in any category, with a main rotor hub inboard strap fitting (fitting) with a part number (P/N) and serial number (S/N) listed in Table 1 to paragraph (a) of this AD.
| Fitting P/Ns | Fitting S/Ns |
|---|---|
| 204-012-102-001 | All. |
| 204-012-102-005 | All. |
| 204-012-102-009 | All, except 7500 or larger with a prefix of “A” or “A-FS.” |
We are adopting a new airworthiness directive (AD) for various restricted category Model HH-1K, TH-1F, TH-1L, UH-1A, UH-1B, UH-1E, UH- 1F, UH-1H, UH-1L, and UH-1P helicopters with certain main rotor hub inboard strap fittings (fittings) installed. This AD requires a magnetic particle inspection (MPI) of the fittings for a crack, and if there is a crack, replacing the fitting with an airworthy fitting. This AD is prompted by reports of cracked fittings on Bell model helicopters and the determination that these same part-numbered fittings may be installed on various restricted category helicopters. These actions are intended to detect a crack in a fitting, which may lead to failure of a fitting, loss of a main rotor blade, and subsequent loss of helicopter control.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
Within 25 hours time-in-service or 15 days, whichever occurs first:
(1) Perform a magnetic particle inspection (MPI) of each fitting for a crack. If an MPI was already performed on a fitting resulting in re-identifying the fitting with “FM” at the end of the P/N or at the end of the P/N on the fitting's component history card or equivalent record, then the requirements of this AD have been met.
(2) If a fitting is cracked, before further flight, replace it with an airworthy fitting.
(3) If a fitting is not cracked, before further flight, re-identify the fitting by adding “FM” at the end of the P/N using a vibrating stylus. The depth of the “FM” must not exceed 0.005 inches or extend within 0.10 inch of the part's edge. Also, add “FM” at the end of the P/N on the fitting's component history card or equivalent record.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
