AD 78-11-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Cessna Aircraft Company | 210M | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 310R | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 340A | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 402B | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 404 | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 414 | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 414A | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | 421C | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | P210N | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | P210R | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | T210M | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
| aircraft | Cessna Aircraft Company | T310R | Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C |
Unsafe Condition
Failure of the autopilot actuator to disengage when the autopilot is disconnected, causing increased flight control forces.
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Required Actions
Disable the Model 400B autopilot by pulling and banding circuit breakers or disconnecting connectors, install a locally fabricated placard indicating 'AUTOPILOT INOPERATIVE', and perform the electrical autopilot actuator modification per Cessna Service Letter No. AV78-6 to return the autopilot to service.
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Compliance Time
before next flight
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Affected Aircraft
Cessna Models 210M, T210M, P210 (Serial Numbers 21061574-21062583, P2100001-P2100010); 310R, T310R (Serial Numbers 310R0501-310R1302, 310R1304-310R1315, 310R1317, 310R1318); 340A (Serial Numbers 340A0001-340A0458, 340A0460-340A0466, 340A0468, 340A0470-340A0483); 402B (Serial Numbers 402B1001-402B1331, 402B1333-402B1338); 404 (Serial Numbers 404-0001-404-0218, 404-0220-404-0222); 414, 414A (Serial Numbers 414-0801-414-0965, 414A0001-414A0032, 414A0034-414A0038, 414A0040-414A0047); 421C (Serial Numbers 421C0001-421C0479, 421C0481-421C0488) with ARC Model 400B autopilot installations.
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Federal Register Abstract
Autopilot Actuator
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-11-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-11-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, ...Show more Subject: Autopilot Actuator Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/05/1978 Make: Cessna Aircraft Company Model: 210M | 310R | 340A | 402B | 404 | 414 | 414A | 421C | P210N | P210R | T210M | T310R Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 78-11-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3225 AD NUMBER: 78-11-05 SUBJECT HEADING: Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C ACTION: SUMMARY: DATES: Effective June 5, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 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. FOOTER:
Document Text
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AD Final Rules - DRS_78-11-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-11-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, ...Show more Subject: Autopilot Actuator Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/05/1978 Make: Cessna Aircraft Company Model: 210M | 310R | 340A | 402B | 404 | 414 | 414A | 421C | P210N | P210R | T210M | T310R Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 78-11-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3225 AD NUMBER: 78-11-05 SUBJECT HEADING: Airworthiness Directives; CESSNA Model 210M, T210M, P210, 310R, T310R, 340A , 402B, 404, 414, 414A, and 421C ACTION: SUMMARY: DATES: Effective June 5, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 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. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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