# AD 79-26-02: GPWS Flap Position Switches

- Type: Airworthiness directive
- Status: Current
- Products: Boeing 737-200 Series
- Effective: December 31, 1979
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Large airplane
- Amendment: 39-3638
- Registered aircraft: 6 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D5E8C705D8DC25BC86256839006DE994.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/79-26-02

## The airworthiness directive

79-26-02 BOEING: Amendment 39-3638. Applies to all Model 737-200 (advanced) airplanes with GPWS flap position switches sensing less than 30 degrees as landing flaps, certificated in all categories. Compliance required as indicated. Accomplish the following: Within the next 1,200 hours time-in-service or six (6) months, whichever comes first, after the effective date of this AD, change the ground proximity warning system flap position switch to sense flaps 30 degrees and 40 degrees as the landing flap positions, and provide a flap override switch for landings that must proceed with flap position of 25 degrees or less. This modification may be accomplished in accordance with modifications approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108.

This amendment becomes effective December 31, 1979.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A16WE](https://openairdocs.org/tcds/A16WE): The Boeing Company; names 1 of 17 models: 737-200 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 737-205](https://openairdocs.org/model/boeing-737-205): 3 aircraft (airframe model)
- [Boeing 737-200](https://openairdocs.org/model/boeing-737-200): 1 aircraft (airframe model)
- [Boeing 737-201](https://openairdocs.org/model/boeing-737-201): 1 aircraft (airframe model)
- [Boeing 737-209](https://openairdocs.org/model/boeing-737-209): 1 aircraft (airframe model)

All 4 models: https://openairdocs.org/ad/79-26-02/models.md
Every aircraft: https://openairdocs.org/ad/79-26-02/aircraft.md

Its text cites no advisory circulars or STCs.

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