# AD 73-13-11: Automatic Pilot Instruments

- Type: Airworthiness directive
- Status: Current
- Products: Textron 19A, 23, A23, A23-19, A23-24, A23A, A24, A24R, B19, B23, C23, M19A and 1 more
- Effective: June 29, 1973
- Superseded by: Nothing supersedes this AD
- Product type: Appliance
- Amendment: 39-1677
- Registered aircraft: 1,232 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/8AF69A17EEA45C8C86256A3300561DC6.0001
- DRS record last changed: January 21, 2026
- Page: https://openairdocs.org/ad/73-13-11

## The airworthiness directive

73-13-11 MITCHELL INDUSTRIES, INC., doing business as EDO-AIRE MITCHELL: Amendment 39-1677. Applies to Mitchell automatic pilot instruments installed in various Beech aircraft with a mechanical wing flap control system in accordance with the following Supplemental Type Certificates:

STC NO. BEECH AIRPLANE MODELS AUTOPILOT MODEL SA1346SW 23, A23, A23A, A23-19, 19A, A24, Century I

A24R, B19, M19A, A23-24, B23,C23 Model AK341

SA1348SW 23, A23, A23A, A23-19, 19A, B19, Century IIB

M19A, A23-24, B23, C23, A24, A24R Model AK342

Compliance required within the next ten (10) hours' time in service after the effective date of this AD, unless already accomplished.

To prevent interference of the flap control system with the automatic pilot roll servo, which may result in loss of aileron control, accomplish the following:

Remove the automatic pilot roll servo assembly and all servo installation brackets from the airplanes or install the cable tensioner Kit PKMB-8 in accordance with Edo-Aire Mitchell Service Bulletin No. MB-8 dated June 7, 1973, or later FAA approved revision, or any other method approved by the Chief, Engineering and Manufacturing Branch, Southwest Region, Federal Aviation Administration, Fort Worth, Texas.

The bulletin mentioned herein may be obtained from Edo-Aire Mitchell, P. O. Box 610, Mineral Wells, Texas 76067.

This amendment becomes effective June 29, 1973.

## 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 12 of 14 models: A23-24, M19A, A24R, A24, A23, A23-19, B23, B19…

## 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: 1,232 (1,232 by airframe model, 0 by engine model)
- Makers: Beech 1,232

Models with the most aircraft:

- [Beech C23](https://openairdocs.org/model/beech-c23): 456 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 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 12 models: https://openairdocs.org/ad/73-13-11/models.md
Every aircraft: https://openairdocs.org/ad/73-13-11/aircraft.md

## Related documents

- [STC SA1346SW](https://openairdocs.org/stc/SA1346SW): Installation of Mitchell automatic flight system model AK341consisting of Century I autopilot and optional Omni Tracker.. Century Flight Systems Inc, Cited in the text
- [STC SA1348SW](https://openairdocs.org/stc/SA1348SW): Installation of Mitchell automatic flight system AK342 consisting of Century IIB autopilot with optional radio coupler.. Century Flight Systems Inc, Cited in the text

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