# AD 73-15-01: Rear Fuselage and Pylon Fittings

- Type: Airworthiness directive
- Status: Current
- Products: Sikorsky S-61A, S-61D, S-61E, S-61L and S-61V
- Effective: July 27, 1973
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-1686
- Registered aircraft: 7 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7FDEDCA3724A533786256A3200681BF8.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/73-15-01

## The airworthiness directive

73-15-01 SIKORSKY AIRCRAFT: Amdt. 39-1686. Applies to all S-61A, S-61D, S- 61E, S-61V and S-61L Helicopters certificated in all categories.

Compliance required as indicated.

To prevent fatigue failures of the rear fuselage and pylon hinge fitting assemblies, accomplish the following:

  (a) For aft fuselage upper and lower hinge fitting assemblies S6120-65118-3, S6120-65118-4, S6120-65118-34, S6120-65121-0, S6120-75702-1 and S6120-75702-2:

  (1) Within the next 15 hours time in service after the effective date of this AD, unless already accomplished, inspect the hinge fittings in accordance with Section 2A of Sikorsky Service Bulletin No. 61B20-6A dated June 18, 1973 or later approved revisions or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration, New England Region;

  (2) Thereafter, on a daily basis inspect the hinge fitting assemblies in accordance with Section 2C of said Bulletin or later approved revisions or an equivalent method approved as above; and

  (3) At each 150 hours time in service after the initial inspection described in (a)(1) or approved equivalent period inspection, inspect the hinge fitting assemblies in accordance with Section 2G or said bulletin or later approved revisions or an equivalent method approved as above.

  (b) For aft fuselage upper and lower hinge fitting assemblies and upper and lower pylon hinge fitting assemblies S6120-65118-3, S6120-65118-4, S6120-65118-34, S6120-65121- 0, S6120-75702-1, S6120-75702-2, S6120-66117-0, S6120-66117-2, S6120-66120-0, S6120- 66120-2;

  (1) Within the next 15 days after the effective date of this AD, unless already accomplished, inspect the aft fuselage hinge fitting lugs and the pylon hinge fitting lugs in accordance with Section 2B of Sikorsky Service Bulletin No. 61B20-6A dated June 18, 1973 or later approved revisions or an equivalent inspection method approved by the Chief, Engineering and Manufacturing Branch,Federal Aviation Administration, New England Region.

  (2) Thereafter, at intervals not to exceed 50 hours time in service from the last inspection, inspect the aft fuselage hinge fitting lugs and the pylon hinge fitting lugs in accordance with Section 2D of said Bulletin, or later approved revisions, or an equivalent inspection method approved as above; and

  (3) At each 150 hours time in service after the initial inspection described in (b) (1) or approved equivalent period inspection, inspect the aft fuselage hinge fitting lugs and the pylon hinge fitting lugs in accordance with Section 2F of said Bulletin, or later approved revisions or an equivalent inspection method as approved above.

  (c) If a crack is found, remove and replace the hinge fitting prior to further flight.

  (d) These inspections are not required on the steel upper hinge fitting assemblies or on any hinge fitting assemblies in the T73 condition.

(This supersedes AD 71-11-7)

This amendment becomes effective July 27, 1973.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H2EA](https://openairdocs.org/tcds/H2EA): Sikorsky Aircraft Corporation; names 4 of 4 models: S-61A, S-61D, S-61V, S-61E
- [TCDS 1H15](https://openairdocs.org/tcds/1H15): Sikorsky Aircraft; names 1 of 4 models: S-61L

## 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: 7 (7 by airframe model, 0 by engine model)
- Makers: Sikorsky 6, Carson Helicopters / Sikorsky 1

Models with the most aircraft:

- [Sikorsky S-61A](https://openairdocs.org/model/sikorsky-s-61a): 5 aircraft (airframe model)
- [Sikorsky S-61L](https://openairdocs.org/model/sikorsky-s-61l): 1 aircraft (airframe model)
- [Carson Helicopters / Sikorsky S61A](https://openairdocs.org/model/carson-helicopters-sikorsky-s61a): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/73-15-01/models.md
Every aircraft: https://openairdocs.org/ad/73-15-01/aircraft.md

Its text cites no advisory circulars or STCs.

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