# AD 77-10-01: Fire Resistant Prop Feathering System

- Type: Airworthiness directive
- Status: Current
- Products: Boeing C54-DC, C54A-DC, C54B-DC, C54D-DC, C54E-DC, C54G-DC and DC-4
- Effective: June 16, 1977
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-2895
- Registered aircraft: 4 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7A8587384879520C862569C9007643BD.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/77-10-01

## The airworthiness directive

77-10-01 MCDONNELL DOUGLAS: Amendment 39-2895. Applies to DC-4 and C-54 series airplanes, certificated in all categories, using Hamilton Standard propellers.

Compliance required by the first engine change after the effective date of this AD or October 1, 1977, whichever occurs earlier, unless previously accomplished in accordance with AD 55-15-03 as amended by Amendment 55-24 to Part 507.

To increase fire resistance integrity of the propeller feathering system against damage by a powerplant fire, all flexible hose components of propeller feathering lines forward of the firewall must be replaced with lines and fittings which will meet the fire resistance requirements of the hose assemblies specified in (a) through (f) herein. However, if the feathering lines in Zone I include a section of steel tubing, flexible hose assemblies located forward of the cylinders and connecting to the governor are not affected by this directive.

The following flexible hose assemblies are acceptable for use in this application:

  (a) Resistoflex SSFR-3800-10 hose assemblies.

  (b) Aeroquip 680-10S hose assemblies with Aeroquip 304 protective sleeves over end fittings (Aeroquip Assembly P/N 304000).

  (c) Aeroquip 309009 hose assemblies.

  (d) Aeroquip 309009-8S hose assemblies (where feathering system requires this size).

  (e) Aeroquip 634000-8 or -10, as applicable, hose assemblies.

  (f) Hose assemblies that fully comply with FAR 37.140 (TSO-C42) and have a pressure rating equal to or greater than that of the propeller feathering system installed on the airplane.

  (g) Equivalent hose assemblies or other means of compliance may be used when approved by the Chief Aircraft Engineering Division, FAA Western Region.

Special flight permits may be issued in accordance with FAR's 21.97 and 21.199 to operate the airplane to a base for the accomplishment of this AD.

This supersedes AD 55-15-03, as amended by Amendment 55-24 to Part 507.

This Amendment becomes effective June 16, 1977.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-762](https://openairdocs.org/tcds/A-762): The Boeing Company; names 7 of 7 models: C54E-DC, C54G-DC, C54B-DC, DC-4, C54A-DC, C54D-DC, C54-DC

## 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: 4 (4 by airframe model, 0 by engine model)
- Makers: Douglas 4

Models with the most aircraft:

- [Douglas C54D-DC](https://openairdocs.org/model/douglas-c54d-dc): 2 aircraft (airframe model)
- [Douglas C54E-DC](https://openairdocs.org/model/douglas-c54e-dc): 1 aircraft (airframe model)
- [Douglas C54G-DC](https://openairdocs.org/model/douglas-c54g-dc): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/77-10-01/models.md
Every aircraft: https://openairdocs.org/ad/77-10-01/aircraft.md

Its text cites no advisory circulars or STCs.

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