AD 91-14-05

final rule

AVCO LYCOMING Model ALF 502L Series Engines

AD Number
91-14-05
Status
final_rule
Effective Date
Product Category
engine
Docket
91-ANE-09
FR Citation
This information is not available.
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
engine Honeywell International Inc. ALF502L AVCO LYCOMING Model ALF 502L Series Engines
engine Honeywell International Inc. ALF502L-2 AVCO LYCOMING Model ALF 502L Series Engines
engine Honeywell International Inc. ALF502L-2A AVCO LYCOMING Model ALF 502L Series Engines
engine Honeywell International Inc. ALF502L-2C AVCO LYCOMING Model ALF 502L Series Engines
engine Honeywell International Inc. ALF502L-3 AVCO LYCOMING Model ALF 502L Series Engines

Unsafe Condition

Complete loss of engine power, uncontained disk failure, and possible damage to the aircraft due to corrosion pitting or cracks in the third stage high compressor rotor disks.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Clean, visually inspect, coat with 'Sermetel W' or 'ALSEAL-518', and reidentify third stage high compressor rotor disks per Textron Lycoming Service Bulletin ALF 502L 72-203, Revision 3. Remove disks with corrosion pitting or cracks prior to further flight. Ferrying allowed under FAR 21.197/21.199.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within the next 500 cycles in service, not to exceed 8,500 cycles since new (CSN) for disks at or above 7,000 CSN on AD effective date; or at or prior to 7,500 CSN for disks below 7,000 CSN on AD effective date.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Avco Lycoming ALF 502L series turbofan engines installed on, but not limited to, Canadair Challenger CL601 aircraft.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

High Compressor Rotor Disks

Applicability Source Text

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AD Number:
91-14-05
Document Type:
AD Final Rules
Docket Number:
91-ANE-09
Subject Heading:
AVCO LYCOMING Model ALF 502L Series Engines
Subject:
High Compressor Rotor Disks
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
07/15/1991
Make:
Honeywell International Inc.
Model:
ALF502L | ALF502L-2 | ALF502L-2A | ALF502L-2C | ALF502L-3
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: 91-14-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   91-ANE-09

AMENDMENT:   39-6955

AD NUMBER:   91-14-05

SUBJECT HEADING:   AVCO LYCOMING Model ALF 502L Series Engines

ACTION:  

SUMMARY:  

DATES:   Effective July 15, 1991.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   91-14-05 AVCO LYCOMING: Amendment 39-6955. Docket No. 91-ANE-09.
Applicability: Avco Lycoming ALF 502L series turbofan engines installed on, but not limited to the Canadair Challenger CL601 aircraft.
Compliance: Required as indicated, unless previously accomplished.
To prevent complete loss of engine power, uncontained disk failure, and possible damage to the aircraft, accomplish the following:
(a) Clean, visually inspect, coat with "Sermetel W" or "ALSEAL-518" and reidentify third stage high compressor (HC) rotor disks in accordance with Textron Lycoming Service Bulletin (SB) ALF 502L 72-203, Revision 3, dated December 7, 1990, as follows:
(1) For those third stage HC disks with 7,000 cycles since new (CSN) or greater on the effective date of this AD, within the next 500 cycles in service, not to exceed 8,500 CSN.
(2) For those third stage HC disks with less than 7,000 CSN on the effective date of this AD, at or prior to accumulating a total of 7,500 CSN.
(b) Remove, prior to further flight, third stage HC disks found with evidence of corrosion pitting or cracks.
(c) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished.
(d) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, an alternate method of compliance with the requirements of this AD or adjustments to the compliance times specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803-5299.
The inspection procedures shall be done in accordance with the following Textron Lycoming service bulletin:

Document No.	Page No.	Issue/Revision	Date
ALF 502L 72-203	1, 2, 4	3	December 7, 1990
ALF 502L 72-203	3, 6	2	August 8, 1990
ALF 502L 72-203	5	1	June 16, 1989

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Textron Lycoming, 550 Main Street, Stratford, Connecticut 06497. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, Massachusetts, or at the Office of the Federal Register, 1100 L Street NW, Room 8401, Washington, D.C.
This amendment (39-6955, AD 91-14-05) becomes effective on July 15, 1991.

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Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_91-14-05.html
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 Feedback
Details
AD Number:
91-14-05
Document Type:
AD Final Rules
Docket Number:
91-ANE-09
Subject Heading:
AVCO LYCOMING Model ALF 502L Series Engines
Subject:
High Compressor Rotor Disks
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
07/15/1991
Make:
Honeywell International Inc.
Model:
ALF502L | ALF502L-2 | ALF502L-2A | ALF502L-2C | ALF502L-3
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: 91-14-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   91-ANE-09

AMENDMENT:   39-6955

AD NUMBER:   91-14-05

SUBJECT HEADING:   AVCO LYCOMING Model ALF 502L Series Engines

ACTION:  

SUMMARY:  

DATES:   Effective July 15, 1991.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   91-14-05 AVCO LYCOMING: Amendment 39-6955. Docket No. 91-ANE-09.
Applicability: Avco Lycoming ALF 502L series turbofan engines installed on, but not limited to the Canadair Challenger CL601 aircraft.
Compliance: Required as indicated, unless previously accomplished.
To prevent complete loss of engine power, uncontained disk failure, and possible damage to the aircraft, accomplish the following:
(a) Clean, visually inspect, coat with "Sermetel W" or "ALSEAL-518" and reidentify third stage high compressor (HC) rotor disks in accordance with Textron Lycoming Service Bulletin (SB) ALF 502L 72-203, Revision 3, dated December 7, 1990, as follows:
(1) For those third stage HC disks with 7,000 cycles since new (CSN) or greater on the effective date of this AD, within the next 500 cycles in service, not to exceed 8,500 CSN.
(2) For those third stage HC disks with less than 7,000 CSN on the effective date of this AD, at or prior to accumulating a total of 7,500 CSN.
(b) Remove, prior to further flight, third stage HC disks found with evidence of corrosion pitting or cracks.
(c) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished.
(d) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, an alternate method of compliance with the requirements of this AD or adjustments to the compliance times specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803-5299.
The inspection procedures shall be done in accordance with the following Textron Lycoming service bulletin:

Document No.	Page No.	Issue/Revision	Date
ALF 502L 72-203	1, 2, 4	3	December 7, 1990
ALF 502L 72-203	3, 6	2	August 8, 1990
ALF 502L 72-203	5	1	June 16, 1989

This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Textron Lycoming, 550 Main Street, Stratford, Connecticut 06497. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, Massachusetts, or at the Office of the Federal Register, 1100 L Street NW, Room 8401, Washington, D.C.
This amendment (39-6955, AD 91-14-05) becomes effective on July 15, 1991.

FOOTER:

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Rights: U.S. Government Public Domain

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