# AD 46-12-02: Engine Mount

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC3A-S1C3G, DC3A-S1CG, DC3A-S4C4G, DC3A-SC3G and DC3A-SCG
- Superseded by: Nothing supersedes this AD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/8F8F0D1A2D5FB15D8625683200735447.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/46-12-02

## The airworthiness directive

46-12-02 DOUGLAS: (Was Service Note 12 of AD-669-3.) Applies to DC3A Aircraft.

Inspection required immediately and every 100 hours thereafter on all aircraft which have beryllium copper engine mount to firewall attach fittings installed.

Inspect the engine mount to firewall attach fittings, P/N 5-81486-4 (with 4-power magnifying glass min.) in the fillet of the spot face for cracks or flaws in the material. If evidence of defects are found, replace with P/N 1042764. If cracks are not found, inspect every 100 hours until next engine change. P/N 5-81486-4 should be replaced with P/N 1042764 at engine change.

(Douglas Service Bulletin No. 238 covers this same subject.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-669](https://openairdocs.org/tcds/A-669): The Boeing Company; names 5 of 10 models: DC3A-S1C3G, DC3A-SCG, DC3A-SC3G, DC3A-S1CG, DC3A-S4C4G

## 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: Douglas 7

Models with the most aircraft:

- [Douglas DC-3A-S1C3G](https://openairdocs.org/model/douglas-dc-3a-s1c3g): 5 aircraft (airframe model)
- [Douglas DC3A-S4C4G](https://openairdocs.org/model/douglas-dc3a-s4c4g): 2 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/46-12-02/models.md
Every aircraft: https://openairdocs.org/ad/46-12-02/aircraft.md

Its text cites no advisory circulars or STCs.

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