# AD 66-19-04: Tail Rotor Blades

- Type: Airworthiness directive
- Status: Current
- Products: Sikorsky S-58A, S-58B, S-58BT, S-58C, S-58D, S-58DT, S-58E, S-58ET, S-58F, S-58FT, S-58G, S-58H and 11 more
- Effective: August 14, 1966
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-269
- Registered aircraft: 76 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0E790CF7A5A6135386256A55006D5E65.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/66-19-04

## The airworthiness directive

66-19-04 SIKORSKY: Amdt. 39-269 Part 39 Federal Register August 4, 1966. Applies to Models S-58 and S-61 Series Helicopters Equipped With Tail Rotor Blades With Serial Numbers Listed in the Appendix of Sikorsky Service Bulletin 58B15-6A, Dated May 18, 1966, or 61B15-5A, Dated May 18, 1966, As Applicable.

Compliance required within the next 50 hours' time in service after the effective date of this AD unless already accomplished.

To prevent operation with tail rotor blades of less than minimum hardness in the flex shank area of the spar, accomplish the following:

  (a) Inspect S 1615-30100, S 6115-30001, and S 6117-30001 Series tail rotor blades in the manner set forth in Sikorsky Service Bulletin 58B15-6A or 61B15-5A as applicable.

  (b) Before further flight, remove from service blades that do not meet the minimum hardness requirements for the flex shank area of the spar specified in the applicable Service Bulletin.

This directive effective August 14, 1966.

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1H11](https://openairdocs.org/tcds/1H11): Centerpointe Aerospace Inc.; names 15 of 15 models: S-58J, S-58FT, S-58C, S-58A, S-58HT, S-58F, S-58G, S-58ET…
- [TCDS 1H15](https://openairdocs.org/tcds/1H15): Sikorsky Aircraft; names 4 of 4 models: S-61R, S-61N, S-61L, S-61NM
- [TCDS H2EA](https://openairdocs.org/tcds/H2EA): Sikorsky Aircraft Corporation; names 4 of 4 models: S-61A, S-61D, S-61V, S-61E

## 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: 76 (76 by airframe model, 0 by engine model)
- Makers: Sikorsky 75, Carson Helicopters / Sikorsky 1

Models with the most aircraft:

- [Sikorsky S-61N](https://openairdocs.org/model/sikorsky-s-61n): 45 aircraft (airframe model)
- [Sikorsky S-58JT](https://openairdocs.org/model/sikorsky-s-58jt): 5 aircraft (airframe model)
- [Sikorsky S-61A](https://openairdocs.org/model/sikorsky-s-61a): 5 aircraft (airframe model)
- [Sikorsky S-58ET](https://openairdocs.org/model/sikorsky-s-58et): 3 aircraft (airframe model)
- [Sikorsky S-58C](https://openairdocs.org/model/sikorsky-s-58c): 3 aircraft (airframe model)
- [Sikorsky S58E](https://openairdocs.org/model/sikorsky-s58e): 3 aircraft (airframe model)
- [Sikorsky S-58J](https://openairdocs.org/model/sikorsky-s-58j): 2 aircraft (airframe model)
- [Sikorsky S-58H](https://openairdocs.org/model/sikorsky-s-58h): 2 aircraft (airframe model)
- [Sikorsky S-58B](https://openairdocs.org/model/sikorsky-s-58b): 1 aircraft (airframe model)
- [Sikorsky S-58D](https://openairdocs.org/model/sikorsky-s-58d): 1 aircraft (airframe model)
- [Sikorsky S-58BT](https://openairdocs.org/model/sikorsky-s-58bt): 1 aircraft (airframe model)
- [Sikorsky S-58DT](https://openairdocs.org/model/sikorsky-s-58dt): 1 aircraft (airframe model)
- [Sikorsky S-61L](https://openairdocs.org/model/sikorsky-s-61l): 1 aircraft (airframe model)
- [Sikorsky S-61NM](https://openairdocs.org/model/sikorsky-s-61nm): 1 aircraft (airframe model)
- [Sikorsky S-61R](https://openairdocs.org/model/sikorsky-s-61r): 1 aircraft (airframe model)
- [Carson Helicopters / Sikorsky S61A](https://openairdocs.org/model/carson-helicopters-sikorsky-s61a): 1 aircraft (airframe model)

All 16 models: https://openairdocs.org/ad/66-19-04/models.md
Every aircraft: https://openairdocs.org/ad/66-19-04/aircraft.md

Its text cites no advisory circulars or STCs.

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