# AD 48-19-03: Elevator Trim Tab Operating Mechanism

- Type: Airworthiness directive
- Status: Current
- Products: Boeing DC-6, DC-6A and DC-6B
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 17 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/39D7A2F45AAA605D862569BC005A78C4.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/48-19-03

## The airworthiness directive

48-19-03 DOUGLAS: Applies to DC-6 Serial Numbers 42854 Through 42896; 43000 Through 43024; 43035 Through 43052; 43055 Through 43058; 43061 Through 43064; and 43105 through 43110.

Compliance required by September 15, 1958.

Due to two failures in flight and to reported excessive looseness in the elevator trim tab operating mechanism, the following must be accomplished:

1. Rework drum, P/N 4344461 into drum, P/N 4357010-4, by boring hole in end of drum 0.8755-0.8745 diameter, 0.188-0.189 deep and concentric within 0.002 full indicator reading, and press in bushing 4357010-2 into hole. Remove nut, P/N 2335472, press in nut, P/N 2357008, in place so that two holes in nut match two holes in drum, P/N 4357010-4, and insert two pins, P/N 1335480, and stake in place. This rework changes jackshaft mechanism assembly, P/N 434460, into P/N 4357010.

2. Rework push-pull tubes, P/N 2344790, into P/N 2357984-2 by cutting off swaged end of tube 1/8 inch so that new tube lengthis 10 inches. Insert large end of plug, P/N 2357980, into tube 1 3/4 inches, drill two 0.161 diameter holes (No. 20 drill) and attach plug to tube with two rivets, P/N AN 430 AD5-16. Machine hex end on socket, P/N 2331924, and install in end of the tube opposite to plug, P/N 2357980. Rework end assemblies, P/N 2331925 into end assemblies, P/N 2357983, and install with locknuts, P/N AN 316-5R and washer 1357982.

Reassemble trim tab mechanism and install on aircraft.

(Douglas Service Bulletin DC-6 No. 123 covers this same subject.)

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 6A3](https://openairdocs.org/tcds/6A3): The Boeing Company; names 1 of 3 models: DC-6A
- [TCDS 6A4](https://openairdocs.org/tcds/6A4): The Boeing Company; names 1 of 2 models: DC-6B
- [TCDS A-781](https://openairdocs.org/tcds/A-781): The Boeing Company; names 1 of 1 models: DC-6

## 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: 17 (17 by airframe model, 0 by engine model)
- Makers: Douglas 17

Models with the most aircraft:

- [Douglas DC-6B](https://openairdocs.org/model/douglas-dc-6b): 9 aircraft (airframe model)
- [Douglas DC-6A](https://openairdocs.org/model/douglas-dc-6a): 7 aircraft (airframe model)
- [Douglas DC-6](https://openairdocs.org/model/douglas-dc-6): 1 aircraft (airframe model)

All 3 models: https://openairdocs.org/ad/48-19-03/models.md
Every aircraft: https://openairdocs.org/ad/48-19-03/aircraft.md

Its text cites no advisory circulars or STCs.

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