# AD 78-11-05: Autopilot Actuator - Type: Airworthiness directive - Status: Current - Products: Cessna 210M, 310R, 340A, 402B, 404, 414, 414A, 421C, P210N, P210R, T210M and T310R - Effective: June 5, 1978 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small airplane - Amendment: 39-3225 - Registered aircraft: 3,106 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/484937909BAFB3FF86256A3400690EE6.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/78-11-05 ## The airworthiness directive 78-11-05 CESSNA: Amendment 39-3225. Applies to Model 210M, T210M and P210 (Serial Numbers 21061574 through 21062583, and P2100001 through P2100010); Model 310R and T310R (Serial Numbers 310R0501 through 310R1302, 310R1304 through 310R1315, 310R1317, and 310R1318); Model 340A (Serial Numbers 340A0001 through 340A0458, 340A0460 through 340A0466, 340A0468, and 340A0470 through 340A0483); Model 402B (Serial Numbers 402B1001 through 402B1331 and 402B1333 through 402B1338); Model 404 (Serial Numbers 404-0001 through 404-0218, and 404-0220 through 404-0222); Model 414 and 414A (Serial Numbers 414-0801 through 414-0965, 414A0001 through 414A0032, 414A0034 through 414A0038, and 414A0040 through 414A0047); and Model 421C (Serial Numbers 421C0001 through 421C0479 and 421C0481 through 421C0488) airplanes incorporating ARC Model 400B autopilot installations. To preclude increased flight control forces caused by an autopilot actuator that has failed to disengage when the autopilot is disconnected, unless already accomplished: A) On airplanes not modified in accordance with Cessna Service Letter No. AV78-6, dated March 31, 1978, or later revision, before next flight, disable the Model 400B autopilot: 1. On affected 300 and 400 series airplanes by pulling and banding autopilot computer (COMP.) and actuator (ACT.) circuit breakers; 2. On affected 210 series airplanes by disconnecting the connector at the roll and pitch actuators and securing these connectors to prevent them from interfering with the flight controls; and install a locally fabricated placard in plain view of the pilot indicating "AUTOPILOT INOPERATIVE." NOTE: The autopilot disabling and installation of a locally fabricated placard required by Paragraph A on affected 300 and 400 series airplanes constitutes preventative maintenance and may be performed by persons authorized to perform preventative maintenance under FAR 43. B) Upon accomplishment of the electrical autopilot actuator modification set forth in Cessna Service Letter No. AV78-6, dated March 31, 1978, or later revision, the autopilot may be returned to service and the "AUTOPILOT INOPERATIVE" placard removed. C) Airplanes may be flown to a base where Paragraph A of this AD may be accomplished if the autopilot is not used. D) Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. This amendment becomes effective June 5, 1978, to all persons except those to whom it has already been made effective by air mail letter from the FAA dated May 11, 1978. ## Affected data sheets (5) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS 3A21](https://openairdocs.org/tcds/3A21): Textron Aviation Inc.; names 4 of 28 models: P210N, T210M, 210M, P210R - [TCDS A7CE](https://openairdocs.org/tcds/A7CE): Textron Aviation Inc.; names 4 of 16 models: 421C, 402B, 414, 414A - [TCDS 3A10](https://openairdocs.org/tcds/3A10): Textron Aviation Inc.; names 2 of 23 models: T310R, 310R - [TCDS 3A25](https://openairdocs.org/tcds/3A25): Textron Aviation Inc.; names 1 of 11 models: 340A - [TCDS A25CE](https://openairdocs.org/tcds/A25CE): Textron Aviation Inc.; names 1 of 2 models: 404 ## 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: 3,106 (3,106 by airframe model, 0 by engine model) - Makers: Cessna 3,106 Models with the most aircraft: - [Cessna 340A](https://openairdocs.org/model/cessna-340a): 543 aircraft (airframe model) - [Cessna 421C](https://openairdocs.org/model/cessna-421c): 496 aircraft (airframe model) - [Cessna P210N](https://openairdocs.org/model/cessna-p210n): 421 aircraft (airframe model) - [Cessna 414A](https://openairdocs.org/model/cessna-414a): 363 aircraft (airframe model) - [Cessna 310R](https://openairdocs.org/model/cessna-310r): 361 aircraft (airframe model) - [Cessna T210M](https://openairdocs.org/model/cessna-t210m): 321 aircraft (airframe model) - [Cessna 414](https://openairdocs.org/model/cessna-414): 242 aircraft (airframe model) - [Cessna T310R](https://openairdocs.org/model/cessna-t310r): 140 aircraft (airframe model) - [Cessna 210M](https://openairdocs.org/model/cessna-210m): 122 aircraft (airframe model) - [Cessna 402B](https://openairdocs.org/model/cessna-402b): 49 aircraft (airframe model) - [Cessna 404](https://openairdocs.org/model/cessna-404): 26 aircraft (airframe model) - [Cessna P210R](https://openairdocs.org/model/cessna-p210r): 22 aircraft (airframe model) All 16 models: https://openairdocs.org/ad/78-11-05/models.md Every aircraft: https://openairdocs.org/ad/78-11-05/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.