AD 75-12-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Honeywell International Inc. | T5313A | AVCO LYCOMING Model T5313A and T5313B Engines |
| engine | Honeywell International Inc. | T5313B | AVCO LYCOMING Model T5313A and T5313B Engines |
Unsafe Condition
Failure of the second stage gas producer cylinder retaining bolts, specifically part numbers MS9060-08 and MS9705-08.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove all P/N MS9060-08 and MS9705-08 retaining bolts within 100 hours time in service after the effective date and replace with new P/N 1-110-262-01 bolts per Avco Lycoming Service Bulletin 0028 Rev 2 or later. Equivalent methods may be approved.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 100 hours time in service after the effective date of this airworthiness directive
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Avco Lycoming T5313A and T5313B model turboshaft engines
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Second Stage Gas Producer Cylinder Retaining Bolt
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-12-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-12-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model T5313A and T5313B Engines Subject: Second Stage Gas Producer Cylinder Retaining Bolt Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/18/1975 Make: Honeywell International Inc. Model: T5313A | T5313B Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 75-12-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2235 AD NUMBER: 75-12-12 SUBJECT HEADING: AVCO LYCOMING Model T5313A and T5313B Engines ACTION: SUMMARY: DATES: Effective June 18, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-12-12 AVCO LYCOMING: Amendment 39-2235. Applies to all Avco Lycoming T5313A and T5313B model turboshaft engines. Compliance required as indicated. To prevent failure of the second stage gas producer cylinder retaining bolts, accomplish the following: a. Within the next 100 hours time in service after the effective date of this airworthiness directive, remove all P/N MS9060-08 retaining bolts and/or P/N MS9705-08 retaining bolts and replace with new P/N 1-110-262-01 retaining bolts in accordance with the instructions set forth in Avco Lycoming Service Bulletin, Product Support No. 0028, Revision 2, dated December 13, 1974, or later revision approved by the Chief, Engineering and Manufacturing Branch, FAA New England Region. b. Equivalent methods of compliance may be approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. Amendment 39-2235 supersedes AD 73-3-2. This amendment becomes effective June 18, 1975. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_75-12-12.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-12-12 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model T5313A and T5313B Engines Subject: Second Stage Gas Producer Cylinder Retaining Bolt Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/18/1975 Make: Honeywell International Inc. Model: T5313A | T5313B Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 75-12-12 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2235 AD NUMBER: 75-12-12 SUBJECT HEADING: AVCO LYCOMING Model T5313A and T5313B Engines ACTION: SUMMARY: DATES: Effective June 18, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-12-12 AVCO LYCOMING: Amendment 39-2235. Applies to all Avco Lycoming T5313A and T5313B model turboshaft engines. Compliance required as indicated. To prevent failure of the second stage gas producer cylinder retaining bolts, accomplish the following: a. Within the next 100 hours time in service after the effective date of this airworthiness directive, remove all P/N MS9060-08 retaining bolts and/or P/N MS9705-08 retaining bolts and replace with new P/N 1-110-262-01 retaining bolts in accordance with the instructions set forth in Avco Lycoming Service Bulletin, Product Support No. 0028, Revision 2, dated December 13, 1974, or later revision approved by the Chief, Engineering and Manufacturing Branch, FAA New England Region. b. Equivalent methods of compliance may be approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. Amendment 39-2235 supersedes AD 73-3-2. This amendment becomes effective June 18, 1975. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
Related Airworthiness Directives
77-17-08
final ruleAVCO LYCOMING Model T53 Series Engines
Unsafe Condition: Failure of the fuel regulator P1 multiplier lever resulting in flameout of the engine.
75-22-02
final ruleAVCO LYCOMING Model T53 Series Engines
Unsafe Condition: Secondary failure of the N2 accessory drive shaft due to binding of the torquemeter boost pump drive shaft.
74-22-07
final ruleAVCO LYCOMING T5313A Engines
Unsafe Condition: Compressor disk or centrifugal impeller assembly failures leading to partial or complete loss of engine power.
71-08-06
final ruleAVCO LYCOMING T5313A and T5313B Engines
Unsafe Condition: Failure of the overspeed pickup gear bearings could lead to secondary failure of the power turbine (N2) accessory drive system.