AD 81-01-06
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bendix Avionics | Primary Servo | Airworthiness Directives; BENDIX AVIONICS: Applies to M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J and 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K having magnetic clutch, P/N 717503-0001, Serial Numbers 16750 through 18396 |
| appliance | Bendix Avionics | Primary Servo | Airworthiness Directives; BENDIX AVIONICS: Applies to M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J and 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K having magnetic clutch, P/N 717503-0001, Serial Numbers 16750 through 18396 |
Unsafe Condition
Failure of the primary servo due to seizure of the magnetic clutches (P/N 717503-0001, Serial Numbers 16750 through 18396).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect and modify the affected primary servos in accordance with Bendix Service Bulletin M-4D-060, dated November 1980, or an equivalent manner approved by the FAA.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 50 hours time in service after the effective date of this AD
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Affected Aircraft
Bendix Avionics M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J, 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K with magnetic clutch P/N 717503-0001, Serial Numbers 16750 through 18396, installed, repaired or overhauled after January 1, 1979, without Modification Number 4.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Autopilot
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_81-01-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-01-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BENDIX AVIONICS: Applies to M-4 (A, B, C, D) Autopilot Primary Servo Mod...Show more Subject: Autopilot Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/12/1981 Make: Bendix Avionics Model: Primary Servo Product Type: Appliance Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 81-01-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4008 AD NUMBER: 81-01-06 SUBJECT HEADING: Airworthiness Directives; BENDIX AVIONICS: Applies to M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J and 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K having magnetic clutch, P/N 717503-0001, Serial Numbers 16750 through 18396 ACTION: SUMMARY: DATES: Effective January 12, 1981. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-01-06 BENDIX AVIONICS: Amendment 39-4008. Applies to M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J and 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K having magnetic clutch, P/N 717503-0001, Serial Numbers 16750 through 18396, installed, repaired or overhauled after January 1, 1979, that do not contain Modification Number 4, as defined in Bendix Service Bulletin M-4D-060. PRIMARY SERVO PRIMARY SERVO PRIMARY SERVO MODEL NUMBER PART NUMBER SERIAL NUMBER *3013E 1U014-01 Any primary servo that has had magnetic clutches installed after January 1, 1979. *3013F 1U014-02 *3013G 1U014-03 3013H 4000523-8501 9530 through 9925 and any primary servo that has been repaired or overhauled after January 1, 1979 3013J 4009506-8501 1775 through 1792 and any primary servo that has been repaired or overhauled after January 1, 1979. 3013K 4009506-8502 2067 through 2110 and any primary servo that has been repaired or overhauled after January 1, 1979. *Older model primary servos which may contain magnetic clutches manufactured by Bendix. Compliance is required as indicated below unless already accomplished. To prevent the possible failure of the primary servo due to seizure of the magnetic clutches (P/N 717503-0001, Serial Numbers 16750 through 18396), accomplish the following: Within the next 50 hours time in service after the effective date of this AD, inspect and modify the affected primary servos in accordance with Bendix Service Bulletin M-4D-060, dated November 1980 or in an equivalent manner approved by the Chief, Engineering and Manufacturing Branch, FAA Southern Region. This amendment is effective January 12, 1981. FOOTER:
Document Text
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AD Final Rules - DRS_81-01-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-01-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BENDIX AVIONICS: Applies to M-4 (A, B, C, D) Autopilot Primary Servo Mod...Show more Subject: Autopilot Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/12/1981 Make: Bendix Avionics Model: Primary Servo Product Type: Appliance Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 81-01-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4008 AD NUMBER: 81-01-06 SUBJECT HEADING: Airworthiness Directives; BENDIX AVIONICS: Applies to M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J and 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K having magnetic clutch, P/N 717503-0001, Serial Numbers 16750 through 18396 ACTION: SUMMARY: DATES: Effective January 12, 1981. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-01-06 BENDIX AVIONICS: Amendment 39-4008. Applies to M-4 (A, B, C, D) Autopilot Primary Servo Models 3013E, 3013F, 3013G, 3013H, 3013J and 3013K and YD-4 Yaw Damper Primary Servos Models 3013J and 3013K having magnetic clutch, P/N 717503-0001, Serial Numbers 16750 through 18396, installed, repaired or overhauled after January 1, 1979, that do not contain Modification Number 4, as defined in Bendix Service Bulletin M-4D-060. PRIMARY SERVO PRIMARY SERVO PRIMARY SERVO MODEL NUMBER PART NUMBER SERIAL NUMBER *3013E 1U014-01 Any primary servo that has had magnetic clutches installed after January 1, 1979. *3013F 1U014-02 *3013G 1U014-03 3013H 4000523-8501 9530 through 9925 and any primary servo that has been repaired or overhauled after January 1, 1979 3013J 4009506-8501 1775 through 1792 and any primary servo that has been repaired or overhauled after January 1, 1979. 3013K 4009506-8502 2067 through 2110 and any primary servo that has been repaired or overhauled after January 1, 1979. *Older model primary servos which may contain magnetic clutches manufactured by Bendix. Compliance is required as indicated below unless already accomplished. To prevent the possible failure of the primary servo due to seizure of the magnetic clutches (P/N 717503-0001, Serial Numbers 16750 through 18396), accomplish the following: Within the next 50 hours time in service after the effective date of this AD, inspect and modify the affected primary servos in accordance with Bendix Service Bulletin M-4D-060, dated November 1980 or in an equivalent manner approved by the Chief, Engineering and Manufacturing Branch, FAA Southern Region. This amendment is effective January 12, 1981. FOOTER:
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