# AD 61-09-01: Elevator Hydraulic Damper Housing

- Type: Airworthiness directive
- Status: Current
- Products: Lockheed Martin 188A and 188C
- Effective: April 7, 1961
- Superseded by: Nothing supersedes this AD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/DF5C00D493ED4840862569B200717F00.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/61-09-01

## The airworthiness directive

61-09-01 LOCKHEED: Amdt. 279 Part 507 Federal Register April 28, 1961. Applies to All 188 Series Aircraft Which Incorporate Hydraulic Damper Housing P/N's 840655-1 and 475645-1 (rudder, elevator, and aileron control systems) Installed Per Lockheed Service Bulletin 88/SB-524 and 88/SB-532.

Compliance required not later than the next 50 hours' time in service.

As a result of an incident involving elevator booster hydraulic damper malfunction, hydraulic damper housing P/N 840655-1 and P/N 475645-1 not identified with blue anodized color must be replaced with new parts identified with blue anodized color as received from the manufacturer or reworked to the following dimensions:

  (a) Length of skirt 0.312 inch plus or minus 0.010 inch.

  (b) Bore of body 1.3800-1.3817 inches.

  (c) Clearance between piston and damper housing 0.0015-0.0040 inch.

  (d) Identify the reworked housing with blue dye or blue paint.

The reinstallation of new or reworked damper housings mustbe accomplished in accordance with instructions in Lockheed Service Letter FS/251702-L dated February 14, 1961.

(Lockheed Service Wire to all operators dated April 7, 1961, applies to this same subject.)

This directive becomes effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated April 7, 1961.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A22](https://openairdocs.org/tcds/4A22): Lockheed Martin Corporation; names 2 of 2 models: 188A, 188C

## 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: Lockheed 4

Models with the most aircraft:

- [Lockheed 188C](https://openairdocs.org/model/lockheed-188c): 3 aircraft (airframe model)
- [Lockheed 188A](https://openairdocs.org/model/lockheed-188a): 1 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/61-09-01/models.md
Every aircraft: https://openairdocs.org/ad/61-09-01/aircraft.md

Its text cites no advisory circulars or STCs.

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