# AD 74-18-10: Horizontal Stabilizer and Elevator

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 707-100 Long Body, 707-100B Long Body, 707-100B Short Body, 707-200, 707-300 Series, 707-300B Series, 707-300C Series, 707-400 Series, 720 Series and 720B Series
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-1945
- Registered aircraft: 6 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/47259030AA8CD769862568320054EF6D.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/74-18-10

## The airworthiness directive

74-18-10 BOEING: Amendment 39-1945. Applies to all model 707/720 series airplanes, certificated in all categories.

Compliance required as indicated. To prevent potential oscillatory longitudinal flight on Boeing models 707/720 series airplanes, accomplish the following: By September 1, 1976, unless already accomplished, inspect and adjust the contour mismatch of the upper surfaces between the horizontal stabilizer and elevator in accordance with Boeing Service Bulletin No. 3151, or later FAA approved revisions or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region.

This amendment becomes effective thirty (30) days after publication in the Federal Register.

## Affected data sheets (3) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4A21](https://openairdocs.org/tcds/4A21): The Boeing Company; names 4 of 4 models: 707-100B Short Body, 707-200, 707-100 Long Body, 707-100B Long Body
- [TCDS 4A26](https://openairdocs.org/tcds/4A26): The Boeing Company; names 4 of 4 models: 707-300B Series, 707-400 Series, 707-300 Series, 707-300C Series
- [TCDS 4A28](https://openairdocs.org/tcds/4A28): The Boeing Company; names 2 of 2 models: 720B Series, 720 Series

## 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: 6 (6 by airframe model, 0 by engine model)
- Makers: Boeing 6

Models with the most aircraft:

- [Boeing 707-338C](https://openairdocs.org/model/boeing-707-338c): 2 aircraft (airframe model)
- [Boeing 707-368C](https://openairdocs.org/model/boeing-707-368c): 1 aircraft (airframe model)
- [Boeing 707-321B](https://openairdocs.org/model/boeing-707-321b): 1 aircraft (airframe model)
- [Boeing 707-323B](https://openairdocs.org/model/boeing-707-323b): 1 aircraft (airframe model)
- [Boeing 707-351B](https://openairdocs.org/model/boeing-707-351b): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/74-18-10/models.md
Every aircraft: https://openairdocs.org/ad/74-18-10/aircraft.md

Its text cites no advisory circulars or STCs.

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