AD 91-15-05

final rule

ROLLS-ROYCE plc Model GEM Mk 530 Series Engines

AD Number
91-15-05
Status
final_rule
Effective Date
Product Category
engine
Docket
91-ANE-19
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
engine Rolls-Royce Limited GEM Mk. 530 ROLLS-ROYCE plc Model GEM Mk 530 Series Engines

Unsafe Condition

External fuel leakage from the hydromechanical fuel control unit (HMU) could result in a fire hazard in the engine nacelle.

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

Required Actions

Perform an HMU leak check inspection within 15 hours time in service after the effective date. Reinspect daily within 30 minutes of last shut-down. Remove HMU from service if leakage is found. X-ray or disassemble inspect HMU at next engine shop visit or by December 31, 1991, and remove incorrectly assembled units. Use specified service bulletins.

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

Compliance Time

within the next 15 hours time in service after the effective date of this AD

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

Affected Aircraft

Rolls-Royce plc GEM Mk 530 series engines installed on, but not limited to, Westland 30 aircraft.

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

Federal Register Abstract

Hydromechanical Fuel Control Unit

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_91-15-05.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
91-15-05
Document Type:
AD Final Rules
Docket Number:
91-ANE-19
Subject Heading:
ROLLS-ROYCE plc Model GEM Mk 530 Series Engines
Subject:
Hydromechanical Fuel Control Unit
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/19/1991
Make:
Rolls-Royce Limited
Model:
GEM Mk. 530
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Superseded AD: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Superseded By: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: 91-15-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   91-ANE-19

AMENDMENT:   39-7068

AD NUMBER:   91-15-05

SUBJECT HEADING:   ROLLS-ROYCE plc Model GEM Mk 530 Series Engines

ACTION:  

SUMMARY:  

DATES:   Effective August 19, 1991.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   91-15-05 ROLLS-ROYCE plc: Amendment 39-7068. Docket No. 91-ANE-19.
Applicability: Rolls-Royce plc (RR) GEM Mk 530 series engines, installed on, but not limited to, Westland 30 aircraft. [[Dart]]
Compliance: Required as indicated, unless previously accomplished.
To prevent external fuel leakage from the hydromechanical fuel control unit (HMU) which could result in a fire hazard in the engine nacelle, accomplish the following:
(a) For engines equipped with Hamilton-Standard Model JFC118-22 HMU, part numbers 779218-3, 779218-6, 779218-9, 779218-12, excluding HMU's marked "MS090-001" adjacent to the identification plate, perform the following:
(1) Perform an HMU leak check inspection in accordance with RR Service Bulletin (SB) GEM- 73-24, dated October 29, 1990, within the next 15 hours time in service after the effective date of this AD.
(2) Thereafter, reinspect the HMU daily for fuel leakage within 30 minutes of the last shut-down of the day, in accordance with RR SB GEM-73-24.
(3) Remove from service, prior to further flight, HMU's exhibiting any fuel leakage when inspected in accordance with paragraphs (a)(1) or (a)(2) of this AD.
(4) X-ray or disassemble inspect the HMU for correct assembly in accordance with the Accomplishment Instructions of Hamilton-Standard (HS) SB JFC118-22-73-10, dated November 21, 1990, at the next engine shop visit or HMU removal, or by December 31, 1991, whichever occurs first.
(5) Remove from service, prior to further flight, HMU's confirmed incorrectly assembled when inspected in accordance with paragraph (a)(4) of this AD.
(6) For HMU's determined to be correctly assembled when inspected in accordance with paragraph (a)(4) of this AD, the repetitive inspections of paragraphs (a)(1) or (a)(2) of this AD are no longer required.
(b) For the purpose of this AD, shop visit is defined as the induction of an engine into a shop for the conduct of maintenance.
(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 Inspector (maintenance, avionics, or operations, as appropriate), 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, Aircraft Certification Service, Engine and Propeller Directorate, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803-5299.
(e) The leak check inspection and the x-ray and disassembly inspection shall be done in accordance with the following documents:

Document	Page	Revision	Date
RR SB GEM-73-24	1-4	Original	October 29, 1990
Total Pages: 4			
HS SB JFC118-22-73-10	1-12	Original	November 21, 1990
Total Pages: 12			

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 the United Technologies Corporation, Hamilton- Standard Division, Technical Publications Department, One Hamilton Road, Windsor Locks, Connecticut 06096- 1010, and Rolls-Royce plc, Leavesden, WD27BZ, England. Copies may be inspected at the

FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Room 311, Burlington, Massachusetts, or at the office of the Federal Register, 1100 L Street, NW, Room 8401, Washington, D.C.
Airworthiness Directive 91-15-05 published in Federal Register on July 23 was not distributed to the public by FAA due to a clerical error in the AD. This corrected version of Airworthiness Directive 91-15-05, Amendment 39-7068, published in the Federal Register on August 8, 1991, becomes effective on August 19, 1991.
This amendment (39-7068, AD 91-15-05) becomes effective on August 19, 1991.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_91-15-05.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
91-15-05
Document Type:
AD Final Rules
Docket Number:
91-ANE-19
Subject Heading:
ROLLS-ROYCE plc Model GEM Mk 530 Series Engines
Subject:
Hydromechanical Fuel Control Unit
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
08/19/1991
Make:
Rolls-Royce Limited
Model:
GEM Mk. 530
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: 91-15-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   91-ANE-19

AMENDMENT:   39-7068

AD NUMBER:   91-15-05

SUBJECT HEADING:   ROLLS-ROYCE plc Model GEM Mk 530 Series Engines

ACTION:  

SUMMARY:  

DATES:   Effective August 19, 1991.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   91-15-05 ROLLS-ROYCE plc: Amendment 39-7068. Docket No. 91-ANE-19.
Applicability: Rolls-Royce plc (RR) GEM Mk 530 series engines, installed on, but not limited to, Westland 30 aircraft. [[Dart]]
Compliance: Required as indicated, unless previously accomplished.
To prevent external fuel leakage from the hydromechanical fuel control unit (HMU) which could result in a fire hazard in the engine nacelle, accomplish the following:
(a) For engines equipped with Hamilton-Standard Model JFC118-22 HMU, part numbers 779218-3, 779218-6, 779218-9, 779218-12, excluding HMU's marked "MS090-001" adjacent to the identification plate, perform the following:
(1) Perform an HMU leak check inspection in accordance with RR Service Bulletin (SB) GEM- 73-24, dated October 29, 1990, within the next 15 hours time in service after the effective date of this AD.
(2) Thereafter, reinspect the HMU daily for fuel leakage within 30 minutes of the last shut-down of the day, in accordance with RR SB GEM-73-24.
(3) Remove from service, prior to further flight, HMU's exhibiting any fuel leakage when inspected in accordance with paragraphs (a)(1) or (a)(2) of this AD.
(4) X-ray or disassemble inspect the HMU for correct assembly in accordance with the Accomplishment Instructions of Hamilton-Standard (HS) SB JFC118-22-73-10, dated November 21, 1990, at the next engine shop visit or HMU removal, or by December 31, 1991, whichever occurs first.
(5) Remove from service, prior to further flight, HMU's confirmed incorrectly assembled when inspected in accordance with paragraph (a)(4) of this AD.
(6) For HMU's determined to be correctly assembled when inspected in accordance with paragraph (a)(4) of this AD, the repetitive inspections of paragraphs (a)(1) or (a)(2) of this AD are no longer required.
(b) For the purpose of this AD, shop visit is defined as the induction of an engine into a shop for the conduct of maintenance.
(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 Inspector (maintenance, avionics, or operations, as appropriate), 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, Aircraft Certification Service, Engine and Propeller Directorate, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803-5299.
(e) The leak check inspection and the x-ray and disassembly inspection shall be done in accordance with the following documents:

Document	Page	Revision	Date
RR SB GEM-73-24	1-4	Original	October 29, 1990
Total Pages: 4			
HS SB JFC118-22-73-10	1-12	Original	November 21, 1990
Total Pages: 12			

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 the United Technologies Corporation, Hamilton- Standard Division, Technical Publications Department, One Hamilton Road, Windsor Locks, Connecticut 06096- 1010, and Rolls-Royce plc, Leavesden, WD27BZ, England. Copies may be inspected at the

FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Room 311, Burlington, Massachusetts, or at the office of the Federal Register, 1100 L Street, NW, Room 8401, Washington, D.C.
Airworthiness Directive 91-15-05 published in Federal Register on July 23 was not distributed to the public by FAA due to a clerical error in the AD. This corrected version of Airworthiness Directive 91-15-05, Amendment 39-7068, published in the Federal Register on August 8, 1991, becomes effective on August 19, 1991.
This amendment (39-7068, AD 91-15-05) becomes effective on August 19, 1991.

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.