AD T83-03-51
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Honeywell International Inc. | ALF502L | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502L-2 | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502L-2A | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502L-2C | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502L-3 | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502R-3 | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502R-3A | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502R-4 | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502R-5 | AVCO LYCOMING Model ALF502 Series Engines |
| engine | Honeywell International Inc. | ALF502R-6 | AVCO LYCOMING Model ALF502 Series Engines |
Unsafe Condition
Fourth stage turbine rotors assembly P/N 2-141-170-23 or -27 may have blades that do not meet the etch inspection requirements, leading to potential failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove all fourth stage turbine rotors assembly P/N 2-141-170-23 or -27 and replace with a rotor that has satisfactorily met the etch inspection requirements per Service Bulletin ALF502-72-0038. Ferrying is allowed under FAR 21.197.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 10 engine operating hours
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Avco Lycoming ALF502 series model turbofan engines with less than 100 hours total operating time.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Fourth Stage Turbine Rotors Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_T83-03-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: T83-03-51 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model ALF502 Series Engines Subject: Fourth Stage Turbine Rotors Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Honeywell International Inc. Model: ALF502L | ALF502L-2 | ALF502L-2A | ALF502L-2C | ALF502L-3 | ALF502R-3 | ALF502R-3A | ALF502R-4 | ALF...Show more 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: AIRWORTHINESS DIRECTIVES FINAL RULES: T83-03-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: T83-03-51 SUBJECT HEADING: AVCO LYCOMING Model ALF502 Series Engines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: T83-03-51 AVCO LYCOMING: Telegram issued February 4, 1983. Applies to Avco Lycoming ALF502 series model turbofan engines. Unless already accomplished for all engines having less than 100 hours total operating time, within the next 10 engine operating hours, remove all fourth stage turbine rotors assembly P/N 2-141-170-23 or -27 and replace with a rotor which has satisfactorily met the etch inspection requirements for the blades per Avco Lycoming Service Bulletin ALF502-72-0038. NOTE: Avco Lycoming will provide replacement fourth stage turbine rotors which have been etch inspected per Service Bulletin ALF502-72-0038. Airplanes may be ferried in accordance with the provisions of FAR 21.197 to a base where the AD can be accomplished. Upon request of an operator an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Engine Certification Branch, FAA, New England Region. This airworthiness directive becomes effective upon receipt. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_T83-03-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: T83-03-51 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model ALF502 Series Engines Subject: Fourth Stage Turbine Rotors Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Honeywell International Inc. Model: ALF502L | ALF502L-2 | ALF502L-2A | ALF502L-2C | ALF502L-3 | ALF502R-3 | ALF502R-3A | ALF502R-4 | ALF...Show more 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: AIRWORTHINESS DIRECTIVES FINAL RULES: T83-03-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: T83-03-51 SUBJECT HEADING: AVCO LYCOMING Model ALF502 Series Engines ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: T83-03-51 AVCO LYCOMING: Telegram issued February 4, 1983. Applies to Avco Lycoming ALF502 series model turbofan engines. Unless already accomplished for all engines having less than 100 hours total operating time, within the next 10 engine operating hours, remove all fourth stage turbine rotors assembly P/N 2-141-170-23 or -27 and replace with a rotor which has satisfactorily met the etch inspection requirements for the blades per Avco Lycoming Service Bulletin ALF502-72-0038. NOTE: Avco Lycoming will provide replacement fourth stage turbine rotors which have been etch inspected per Service Bulletin ALF502-72-0038. Airplanes may be ferried in accordance with the provisions of FAR 21.197 to a base where the AD can be accomplished. Upon request of an operator an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Engine Certification Branch, FAA, New England Region. This airworthiness directive becomes effective upon receipt. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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