# AD 63-21-04: Elevator Trim Tabs

- Type: Airworthiness directive
- Status: Current
- Products: Air Trading Navy PV-1 and 18
- Effective: January 10, 1964
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Registered aircraft: 2 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/47F185B02E929E8F862569B6005D98D4.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/63-21-04

## The airworthiness directive

63-21-04 LOCKHEED: Amdt. 625 Part 507 Federal Register October 2, 1963. Applies to All Models L-18 and PV-1 Airplanes Equipped With Spartan Electrically Actuated Elevator Trim Tabs.

Compliance required as indicated.

To prevent runaway operation of the electrically operated trim tab actuators, accomplish the following:

  (a) Within 30 hours' time in service after the effective date of this AD unless already accomplished, electrically deactivate the elevator trim tab.

  (b) Any tab deactivated may be reactivated when one of the following has been accomplished:

  (1) On any Lockheed Model 18 airplane with Spartan electrically actuated elevator trim tab, the trim tab installation is made in accordance with STC SA2-183.

  (2) An FAA approved modification to the speed and limits of actuation is accomplished. Modifications must be approved by the Chief of an FAA Engineering and Manufacturing Branch.

This directive effective November 1, 1963.

Revised January 10, 1964.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-723](https://openairdocs.org/tcds/A-723): Lockheed Martin Aeronautics Company; names 1 of 1 models: 18
- [TCDS LTC AL-13](https://openairdocs.org/tcds/LTC%20AL-13): Air Trading Corporation; names 1 of 3 models: Navy PV-1

## 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: 2 (2 by airframe model, 0 by engine model)
- Makers: Lockheed 2

Models with the most aircraft:

- [Lockheed 18](https://openairdocs.org/model/lockheed-18): 2 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/63-21-04/models.md
Every aircraft: https://openairdocs.org/ad/63-21-04/aircraft.md

Its text cites no advisory circulars or STCs.

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