# AD 75-04-02: Main Rotor Spindles

- Type: Airworthiness directive
- Status: Current
- Products: Orlando Helicopter Airways CH-19E, H-19A, H-19D, H-19G, HRS-1/CH-19, HRS-3/H-19B, UH-19D, S-55, S-55B, S-55C and S62A
- Effective: February 19, 1975
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-2082
- Registered aircraft: 27 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5B5DAD41727276FF86256A560045AF5E.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/75-04-02

## The airworthiness directive

75-04-02 SIKORSKY AIRCRAFT: Amendment 39-2082. Applies to S-55, S-55B, S-55C and S-62A Helicopters certificated in all categories, including military type HRS-1, HRS-3, CH-19, H-19B, H-19G, H-19A, H-19D, HO4S-3G, UH-19D, H19D5, UH-19B, UH-19D helicopters, equipped with P/N S10-10-3325-1 and S10-10-3325-2 main rotor spindles.

  (a) Within the next 10 hours' time in service after the effective date of this AD, unless already accomplished within the preceding 50 hours' time in service, conduct a dye penetrant inspection of the exposed areas of the lugs of the main rotor spindles.

  (b) If a crack is found during the above inspection, replace the cracked spindle with a spindle that has been inspected in accordance with paragraph (a) above and found to be free of cracks, prior to flight.

  (c) Report in writing any cracks found during the inspection of paragraph (a) to: Chief, Engineering and Manufacturing Branch, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803. Each report must include the length and location of the cracks and the total time in service of the spindle.

Sikorsky message SST62A6C74.3 covers this inspection.

This amendment becomes effective February 19, 1975.

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS HR1SO](https://openairdocs.org/tcds/HR1SO): Orlando Helicopter Airways Inc.; names 7 of 10 models: CH-19E, H-19A, HRS-3/H-19B, UH-19D, H-19G, H-19D, HRS-1/CH-19
- [TCDS 1H4](https://openairdocs.org/tcds/1H4): Centerpointe Aerospace Inc.; names 3 of 3 models: S-55C, S-55, S-55B
- [TCDS 1H13](https://openairdocs.org/tcds/1H13): Centerpointe Aerospace Inc.; names 1 of 1 models: S62A

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 27 (27 by airframe model, 0 by engine model)
- Makers: Sikorsky 25, Sikorsky/Orlando 1, Sikorsky/Vertical 1

Models with the most aircraft:

- [Sikorsky S-55B](https://openairdocs.org/model/sikorsky-s-55b): 9 aircraft (airframe model)
- [Sikorsky UH-19D](https://openairdocs.org/model/sikorsky-uh-19d): 6 aircraft (airframe model)
- [Sikorsky S-55](https://openairdocs.org/model/sikorsky-s-55): 3 aircraft (airframe model)
- [Sikorsky S55B](https://openairdocs.org/model/sikorsky-s55b): 3 aircraft (airframe model)
- [Sikorsky H-19D](https://openairdocs.org/model/sikorsky-h-19d): 3 aircraft (airframe model)
- [Sikorsky/Orlando S-55](https://openairdocs.org/model/sikorsky-orlando-s-55): 1 aircraft (airframe model)
- [Sikorsky CH-19E](https://openairdocs.org/model/sikorsky-ch-19e): 1 aircraft (airframe model)
- [Sikorsky/Vertical S-55](https://openairdocs.org/model/sikorsky-vertical-s-55): 1 aircraft (airframe model)

All 8 models: https://openairdocs.org/ad/75-04-02/models.md
Every aircraft: https://openairdocs.org/ad/75-04-02/aircraft.md

Its text cites no advisory circulars or STCs.

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