AD 90-12-05

final rule

PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.

AD Number
90-12-05
Status
final_rule
Effective Date
Product Category
engine
Docket
90-ANE-10
FR Citation
This information is not available.
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
engine Pratt & Whitney Canada Corp. PT6A-15AG PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.
engine Pratt & Whitney Canada Corp. PT6A-27 PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.
engine Pratt & Whitney Canada Corp. PT6A-28 PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.
engine Pratt & Whitney Canada Corp. PT6A-29 PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.
engine Pratt & Whitney Canada Corp. PT6A-34 PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.
engine Pratt & Whitney Canada Corp. PT6A-34AG PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.

Unsafe Condition

The development of an unsafe condition which could result in an uncontained engine failure.

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

Required Actions

Remove the engines from service within 30 calendar days after the effective date. Return to service requires either a complete engine overhaul per PWC manual or submission of records for FAA approval including life-limited components' service history, inspection records, FAA-approved data compliance evidence, test data, and accident involvement lists.

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

Compliance Time

within the next 30 calendar days after the effective date of this AD

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

Affected Aircraft

Pratt & Whitney Canada PT6A series engines with specific models and serial numbers repaired by Gregory Flying Service/Airforce Turbine Service in Tynan, Texas.

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

Federal Register Abstract

Engine Overhaul

Applicability Source Text

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AD Final Rules - DRS_90-12-05.html
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AD Number:
90-12-05
Document Type:
AD Final Rules
Docket Number:
90-ANE-10
Subject Heading:
PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforc...Show more
Subject:
Engine Overhaul
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
05/30/1990
Make:
Pratt & Whitney Canada Corp.
Model:
PT6A-15AG | PT6A-27 | PT6A-28 | PT6A-29 | PT6A-34 | PT6A-34AG
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: 90-12-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   90-ANE-10

AMENDMENT:   39-6607

AD NUMBER:   90-12-05

SUBJECT HEADING:   PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.

ACTION:  

SUMMARY:  

DATES:   Effective May 30, 1990.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   90-12-05 PRATT & WHITNEY CANADA: Amendment 39-6607. Docket No. 90-ANE-10.

Applicability: Pratt & Whitney Canada (PWC) PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service (hereafter identified as Gregory Flying Service), located in Tynan, Texas. The affected engines are identified by model and serial number as follows:


MODEL	SERIAL NO.	MODEL	SERIAL NO.
PT6A-15AG	PCE 14012	PT6A-34AG	PCE 56433
PT6A-15AG	PCE 14018	PT6A-34AG	PCE 56466
PT6A-15AG	PCE 14028	PT6A-34AG	PCE 56471
PT6A-34	PCE 38093	PT6A-34AG	PCE 56516
PT6A-28	PCE 40023	PT6A-34AG	PCE 56522
PT6A-27	PCE 41704	PT6A-34AG	PCE 56527
PT6A-28	PCE 51327	PT6A-34AG	PCE 56612
PT6A-29	PCE 51426	PT6A-34AG	PCE 56628
PT6A-34	PCE 56089	PT6A-34AG	PCE 56650
PT6A-34AG	PCE 56381	PT6A-34AG	PCE 56717
PT6A-34AG	PCE 56405	PT6A-34AG	PCE 56773

Compliance: Required as indicated, unless already accomplished.

To prevent the development of an unsafe condition which could result in an uncontained engine failure, accomplish the following:

(a) Remove from service those engines identified above within the next 30 calendar days after the effective date of this AD.

(b) Return to service engines removed from service in accordance with paragraph (a) by accomplishing either one of the two following requirements:

(1) Accomplish a complete engine overhaul in accordance with the requirements of the appropriate PWC overhaul manual.

(2) Submit to the FAA, Manager, Engine Certification Office, through the cognizant FAA Airworthiness Inspector, all the pertinent records identified below for review, and obtain a written FAA approval prior to returning an engine to service:

(i) For the parts, sub-assemblies, accessories, or components of engines that were subjected to repair or maintenance activities during the last shop visit at Gregory Flying Service, provide the following:

(1) A list of all life-limited components by serial number, service history, and their current status as required by FAR Part 135, Section 439, or FAR Part 91, Section 173, as appropriate, and records establishing the origin and/or the prior service history of the subject parts.

(2) Records of accomplishment of the required inspections, checks, tests, as applicable, in accordance with PWC engine manual requirements that establish the components' airworthiness.

(ii) All repair, maintenance, and inspection records, concerning the last shop visit at Gregory Flying Service, as required by FAR Part 135, Section 439, or FAR Part 91, Section 173, as appropriate.

(iii) Substantiating evidence that the work performed during the last shop visit at Gregory Flying Service was done in accordance with FAA approved data as required by the FAR's.

(iv) Engine acceptance test data or engine installed test data, accomplished after the repair, whichever is applicable.

(v) A list by part number or serial number of any engine, part, sub-assembly, accessory, or component acquired from Gregory Flying Service that has been involved in an accident.

Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (Pub. L. 96-511) and have been assigned OMB Control No. 2120-0056.

(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 time specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803.

This amendment (39-6607, AD 90-12-05) becomes effective on May 30, 1990.

FOOTER:

Document Text

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AD Final Rules - DRS_90-12-05.html
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Details
AD Number:
90-12-05
Document Type:
AD Final Rules
Docket Number:
90-ANE-10
Subject Heading:
PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforc...Show more
Subject:
Engine Overhaul
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
05/30/1990
Make:
Pratt & Whitney Canada Corp.
Model:
PT6A-15AG | PT6A-27 | PT6A-28 | PT6A-29 | PT6A-34 | PT6A-34AG
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: 90-12-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   90-ANE-10

AMENDMENT:   39-6607

AD NUMBER:   90-12-05

SUBJECT HEADING:   PRATT & WHITNEY CANADA PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service.

ACTION:  

SUMMARY:  

DATES:   Effective May 30, 1990.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   90-12-05 PRATT & WHITNEY CANADA: Amendment 39-6607. Docket No. 90-ANE-10.

Applicability: Pratt & Whitney Canada (PWC) PT6A series turbopropeller engines repaired by Gregory Flying Service/Airforce Turbine Service (hereafter identified as Gregory Flying Service), located in Tynan, Texas. The affected engines are identified by model and serial number as follows:


MODEL	SERIAL NO.	MODEL	SERIAL NO.
PT6A-15AG	PCE 14012	PT6A-34AG	PCE 56433
PT6A-15AG	PCE 14018	PT6A-34AG	PCE 56466
PT6A-15AG	PCE 14028	PT6A-34AG	PCE 56471
PT6A-34	PCE 38093	PT6A-34AG	PCE 56516
PT6A-28	PCE 40023	PT6A-34AG	PCE 56522
PT6A-27	PCE 41704	PT6A-34AG	PCE 56527
PT6A-28	PCE 51327	PT6A-34AG	PCE 56612
PT6A-29	PCE 51426	PT6A-34AG	PCE 56628
PT6A-34	PCE 56089	PT6A-34AG	PCE 56650
PT6A-34AG	PCE 56381	PT6A-34AG	PCE 56717
PT6A-34AG	PCE 56405	PT6A-34AG	PCE 56773

Compliance: Required as indicated, unless already accomplished.

To prevent the development of an unsafe condition which could result in an uncontained engine failure, accomplish the following:

(a) Remove from service those engines identified above within the next 30 calendar days after the effective date of this AD.

(b) Return to service engines removed from service in accordance with paragraph (a) by accomplishing either one of the two following requirements:

(1) Accomplish a complete engine overhaul in accordance with the requirements of the appropriate PWC overhaul manual.

(2) Submit to the FAA, Manager, Engine Certification Office, through the cognizant FAA Airworthiness Inspector, all the pertinent records identified below for review, and obtain a written FAA approval prior to returning an engine to service:

(i) For the parts, sub-assemblies, accessories, or components of engines that were subjected to repair or maintenance activities during the last shop visit at Gregory Flying Service, provide the following:

(1) A list of all life-limited components by serial number, service history, and their current status as required by FAR Part 135, Section 439, or FAR Part 91, Section 173, as appropriate, and records establishing the origin and/or the prior service history of the subject parts.

(2) Records of accomplishment of the required inspections, checks, tests, as applicable, in accordance with PWC engine manual requirements that establish the components' airworthiness.

(ii) All repair, maintenance, and inspection records, concerning the last shop visit at Gregory Flying Service, as required by FAR Part 135, Section 439, or FAR Part 91, Section 173, as appropriate.

(iii) Substantiating evidence that the work performed during the last shop visit at Gregory Flying Service was done in accordance with FAA approved data as required by the FAR's.

(iv) Engine acceptance test data or engine installed test data, accomplished after the repair, whichever is applicable.

(v) A list by part number or serial number of any engine, part, sub-assembly, accessory, or component acquired from Gregory Flying Service that has been involved in an accident.

Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (Pub. L. 96-511) and have been assigned OMB Control No. 2120-0056.

(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 time specified in this AD may be approved by the Manager, Engine Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803.

This amendment (39-6607, AD 90-12-05) becomes effective on May 30, 1990.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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