# AD 78-04-01: Wing Flap Control

- Type: Airworthiness directive
- Status: Current
- Products: Textron 19A, 23, A23, A23-19, A23-24, A23A, A24, A24R, B19, B23, B24R, C23 and 1 more
- Effective: February 20, 1978
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-3139
- Registered aircraft: 1,525 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/2E454F2D8830D01686256A080072D812.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/78-04-01

## The airworthiness directive

78-04-01 BEECH: Amendment 39-3139. Applies to the following models and serial number airplanes, equipped with manually operated wing flaps, certificated in all categories:

MODEL SERIAL NUMBERS 23, A23, A23A, B23, and C23 M-1 through M-1979 A23-19, 19A and B19 MB-1 through MB-866 A23-24 and A24 MA-1 through MA-368 A24R, B24R AND C24R MC-2 through MC-536

COMPLIANCE: Required a indicated unless already accomplished.

To prevent failure of the wing flap control weld assembly and resulting possible unwanted in-flight retraction of the wing flaps, within the next 50 hours time-in-service after the effective date of this AD, accomplish the following in accordance with Beechcraft Service Instructions No. 0940 or later approved revisions:

A) Remove flap control weld assembly and install Beech P/N 169-524024-85 flap control weld assembly.

B) Any equivalent means of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This amendment becomes effective on February 20, 1978.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A1CE](https://openairdocs.org/tcds/A1CE): Textron Aviation Inc.; names 13 of 14 models: A23-24, A24R, A24, A23, A23-19, B23, B19, 23…

## 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: 1,525 (1,525 by airframe model, 0 by engine model)
- Makers: Beech 1,525

Models with the most aircraft:

- [Beech C23](https://openairdocs.org/model/beech-c23): 456 aircraft (airframe model)
- [Beech C24R](https://openairdocs.org/model/beech-c24r): 176 aircraft (airframe model)
- [Beech 23](https://openairdocs.org/model/beech-23): 147 aircraft (airframe model)
- [Beech B19](https://openairdocs.org/model/beech-b19): 145 aircraft (airframe model)
- [Beech A23-24](https://openairdocs.org/model/beech-a23-24): 121 aircraft (airframe model)
- [Beech B24R](https://openairdocs.org/model/beech-b24r): 117 aircraft (airframe model)
- [Beech A23](https://openairdocs.org/model/beech-a23): 85 aircraft (airframe model)
- [Beech A23-19](https://openairdocs.org/model/beech-a23-19): 72 aircraft (airframe model)
- [Beech B23](https://openairdocs.org/model/beech-b23): 62 aircraft (airframe model)
- [Beech A23A](https://openairdocs.org/model/beech-a23a): 51 aircraft (airframe model)
- [Beech A24R](https://openairdocs.org/model/beech-a24r): 49 aircraft (airframe model)
- [Beech 19A](https://openairdocs.org/model/beech-19a): 41 aircraft (airframe model)
- [Beech B-19 SPORT](https://openairdocs.org/model/beech-b-19-sport): 2 aircraft (airframe model)
- [Beech C 23](https://openairdocs.org/model/beech-c-23): 1 aircraft (airframe model)

All 14 models: https://openairdocs.org/ad/78-04-01/models.md
Every aircraft: https://openairdocs.org/ad/78-04-01/aircraft.md

Its text cites no advisory circulars or STCs.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.