# AD 47-51-04: Propeller Antiheat Shield

- Type: Airworthiness directive
- Status: Current
- Products: Airlift International C-46A, C-46D, C-46F, C-46R, C-46E, C-46A, C-46D, C-46E, C-46F, C-46A, C-46D, C-46F and 3 more
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 7 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/3F7F6DB4017AE77B862569A800699D3E.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-51-04

## The airworthiness directive

47-51-04 CURTISS-WRIGHT Applies to All C-46 Series Airplanes Incorporating Hamilton Standard Propellers.

Compliance required by March 1, 1948.

To eliminate failure of the propeller flexible feathering line, an antiheat shield shall be installed in accordance with the following instructions:

  (a) Remove the engine cowling adjacent to the propeller feathering line and inspect the flexible propeller feathering hose and lagging material (if installed) for disintegration and deterioration. Replace hose if deterioration is evident.

  (b) Fabricate the antiheat shield and attaching clamps as shown in Figure 1.

  (c) Place antiheat shield over the flexible hose and mount the shield on the engine mount by use of the clamps shown in Figure 1. The shield should be centered over the flexible hose. It may be necessary to rebend the metal feathering line slightly to achieve proper centering.

  (d) Upon completion of installation, check operation of propeller feathering system.

(The above information is also contained in Army Air Forces Technical Order 01-25L- 105 dated April 2, 1947. Copies of this Technical Order are not available for distribution by the FAA.)

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 2A5](https://openairdocs.org/tcds/2A5): Tempo Design Corporation; names 2 of 2 models: C-46/CW20-T, Super C-46/CW20-T
- [TCDS 3A2](https://openairdocs.org/tcds/3A2): Airlift International Inc.; names 1 of 4 models: C-46R

## 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: Curtiss Wright 7

Models with the most aircraft:

- [Curtiss Wright C-46F](https://openairdocs.org/model/curtiss-wright-c-46f): 4 aircraft (airframe model)
- [Curtiss Wright C-46A](https://openairdocs.org/model/curtiss-wright-c-46a): 1 aircraft (airframe model)
- [Curtiss Wright C-46D](https://openairdocs.org/model/curtiss-wright-c-46d): 1 aircraft (airframe model)
- [Curtiss Wright C-46R](https://openairdocs.org/model/curtiss-wright-c-46r): 1 aircraft (airframe model)

All 4 models: https://openairdocs.org/ad/47-51-04/models.md
Every aircraft: https://openairdocs.org/ad/47-51-04/aircraft.md

Its text cites no advisory circulars or STCs.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.