# AD 47-42-02: Cowling Fire Seal

- Type: Airworthiness directive
- Status: Current
- Products: Boeing C54-DC, C54A-DC, C54B-DC, C54D-DC, C54E-DC, C54G-DC and DC-4
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 4 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/F75AC5AEE225D48A862569BB00753A93.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-42-02

## The airworthiness directive

47-42-02 DOUGLAS: (Was Mandatory Note 21 of AD-762-7.) Applies to C-54 and DC-4 Aircraft.

To be accomplished as soon as possible but in any case not later than the first engine change after November 15, 1947.

It has been found that on some airplanes certain rework has been accomplished on the fire seal between the accessories section and the nacelle at the upper cowling former at the point where the carburetor airscoop skin rests on top of the firewall. This rework creates a hazardous condition by providing an opening from the accessories section into the nacelle, through the access hole under the non-ram air intake fairing.

Inspect all airplanes to ascertain that a fire seal is provided in this area. If the cowling fire seal has been cut away it must be replaced either with the original type seal or with a new type seal.

(Douglas Service Bulletin DC-4 No. 19 covers a new type fire seal.)

## 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/47-42-02/models.md
Every aircraft: https://openairdocs.org/ad/47-42-02/aircraft.md

Its text cites no advisory circulars or STCs.

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