Published 2004-11-26 · Federal Register document 04-25791
Airworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company, Allison Gas Turbine Division, and Detroit Diesel Allison) (RRC) Models 250-C30R/3, -C30R/3M, -C47B, and -C47M Turboshaft Engines
Publication summary
The FAA is superseding an existing airworthiness directive (AD) for RRC models 250-C30R/3, -C30R/3M, -C47B, and -C47M turboshaft engines. That AD currently requires initial and repetitive electrical signal inspections of the hydromechanical unit (HMU) Power Lever Angle (PLA) potentiometer. This ad continues to require those inspections and adds replacement of the existing HMU with a new design HMU as a mandatory terminating action to the repetitive inspection requirements. This AD results from the manufacturer releasing a redesigned HMU that has a dual-element potentiometer. We are issuing this AD to prevent uncommanded and sudden changes in engine power.
Why this record is shown
Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:13.905821+00:00. The title, summary and date are source facts.
- Source revision
- federal_register_ad_metadata_2004-cb1e1f18d61cac01
- Source row
- results[500]
- Raw source SHA-256
- cb1e1f18d61cac01616802134d899b0c8ce1a9f79716b5ee037f78e4cb53a00a
Final-rule publication
Recorded publication clauses
- AD identifier printed in this edition
- 2004-24-04
- Effective date printed in this edition
- 2005-01-03
Read 11 complete recorded clauses
Effective Date
Effective Date
(a) This AD becomes effective January 3, 2005.
Exact source excerpt. Text positions 6267–6335, end exclusive, in the original decoded publication. SHA-256: eac8e3ca0b74774a403372825e522beeb3b1d2d9e214f7c49cdb33a27ac0fac4
Affected ADs
Affected ADs
(b) This AD supersedes AD 2003-13-10.
Exact source excerpt. Text positions 6335–6392, end exclusive, in the original decoded publication. SHA-256: 87ede85f6afae4221cb88386995f60185b4c5634a84ee37b09a1851d88250948
Applicability wording · Applicability
Applicability
(c) This AD applies to Rolls-Royce Corporation (formerly Allison
Engine Company, Allison Gas Turbine Division, and Detroit Diesel
Allison) (RRC) models 250-C30R/3, -C30R/3M, -C47B, and -C47M
turboshaft engines that have a hydromechanical unit (HMU) with a
part number (P/N) listed in 1.A. Group A of RRC Alert Commercial
Engine Bulletins (ACEB) No. CEB A-73-3103, Revision 4, dated
December 2, 2003; and No. CEB A-73-6030, Revision 4, dated December
2, 2003. These engines are installed on, but not limited to, Bell
OH-58D, Bell Helicopter Textron 407, Boeing AH/MH-6M, and MD
Helicopters Inc. 600N helicopters.
Exact source excerpt. Text positions 6392–7033, end exclusive, in the original decoded publication. SHA-256: 3fd645d39ba213a3d61e24b7a74e16f3ccfb7cbd83ee6827d67164b9540775d9
Unsafe Condition
Unsafe Condition
(d) This AD results from the manufacturer releasing a redesigned
HMU that has a dual-element potentiometer. The actions specified in
this AD are intended to prevent uncommanded and sudden changes in
engine power.
Exact source excerpt. Text positions 7033–7272, end exclusive, in the original decoded publication. SHA-256: c8be501429e6df0490ea30a461d9a9f5ebb43973ca298454888f4d3c09c5cc1b
Compliance
Compliance
(e) Compliance with this AD is required as indicated, unless
already done.
Exact source excerpt. Text positions 7272–7365, end exclusive, in the original decoded publication. SHA-256: f2767ac8794a66018ca0aa7dead39c7635f1f75ecb1b1b2d285481991dd25f6c
Initial Inspection
Initial Inspection
(f) Perform an initial electrical signal inspection of the HMU
Power Lever Angle (PLA) potentiometer, within 300 flight hours (FH)
after the effective date of this AD. Use paragraphs 2.B. through
2.B.(8) and 2.B.(10) of the Accomplishment Instructions of RRC ACEB
No. CEB A-73-3103, Revision 4, dated December 2, 2003; or No. CEB A-
73-6030, Revision 4, dated December 2, 2003; to perform the
inspection.
(g) Replace the HMU before further flight if the electrical
signal inspection result is unacceptable.
Exact source excerpt. Text positions 7365–7907, end exclusive, in the original decoded publication. SHA-256: d305e1e3b9e535467fd20f0be8e9e291a5f878892802a8d7d353a667a19d2f98
Repetitive Inspections
Repetitive Inspections
(h) Thereafter, perform repetitive electrical signal inspections
of the HMU PLA potentiometer within 300 FH of the last inspection.
Use paragraphs 2.B. through 2.B.(8) and 2.B.(10) of the
Accomplishment Instructions of RRC ACEB No. CEB A-73-3103, Revision
4, dated December 2, 2003; or No. CEB A-73-6030, Revision 4, dated
December 2, 2003; to perform the inspection.
(i) Replace the HMU before further flight if the electrical
signal inspection result is unacceptable.
Exact source excerpt. Text positions 7907–8416, end exclusive, in the original decoded publication. SHA-256: a87977bc7ccfb46ea32a059dd9387c0df307ba161fc966ac9259d063ea1c0f1e
Mandatory Terminating Action
Mandatory Terminating Action
(j) Replace the HMU with an HMU that has a P/N not specified in
this AD within 600 FH after the effective date of this AD, or
January 31, 2005, whichever occurs earlier. Replacing the HMU with
an HMU that has a P/N not specified in this AD terminates the
repetitive inspection requirement specified in paragraph (h) of this
AD.
Exact source excerpt. Text positions 8416–8784, end exclusive, in the original decoded publication. SHA-256: ff9f283282a203277f39fddc4c3c4713fc05c4d7c6eda9f15cb858fe0fa88b61
Alternative Methods of Compliance
Alternative Methods of Compliance
(k) Alternative methods of compliance must be requested in
accordance with 14 CFR part 39.19, and must be approved by the
Manager, Chicago Aircraft Certification Office, FAA.
Exact source excerpt. Text positions 8784–9001, end exclusive, in the original decoded publication. SHA-256: 98ff8d4a9ec3f9e8abe7b5638f6dcdbf5af4513a75e80d221ed7fd54643d0c5b
Material Incorporated by Reference
Material Incorporated by Reference
(l) You must use the Rolls-Royce Corporation Alert Commercial
Engine Bulletins (ACEBs) listed in Table 1 of this AD to perform the
inspections required by this AD. The Director of the Federal
Register approved the incorporation by reference of the documents
listed in Table 1 of this AD in accordance with 5 U.S.C. 552(a) and
1 CFR part 51. You can get a copy from Rolls-Royce Corporation, P.O.
Box 420, Indianapolis, IN 46206-0420; telephone (317) 230-6400; fax
(317) 230-4243. You can review copies at the FAA, New England
Region, Office of the Regional Counsel, 12 New England Executive
Park, Burlington, MA; or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. Table 1 follows:
Table 1.--Incorporation by Reference
----------------------------------------------------------------------------------------------------------------
Page number(s) shown Revision level shown
Service bulletin on the page on the page Date shown on the page
----------------------------------------------------------------------------------------------------------------
CEB A-73-3103, Total Pages: 20.... All................. 4.................... December 2, 2003.
CEB A-73-6030, Total Pages: 20.... All................. 4.................... December 2, 2003.
----------------------------------------------------------------------------------------------------------------
[[Page 68771]]
Exact source excerpt. Text positions 9001–10744, end exclusive, in the original decoded publication. SHA-256: 5c9f969035683150e008c816a5a556cff1936b3678d305f5422f41f13c6e43dd
Related Information
Related Information
(m) None.
Exact source excerpt. Text positions 10744–10779, end exclusive, in the original decoded publication. SHA-256: 23bbad44d56134f7c0105b30679b09e2e904f3159464b82bbd35ddc21c1b5e33
No replacement link has been established from this edition. The complete historical rule chain and current legal effect remain unknown.
Find all recorded historical references to AD 2004-24-04 · 0 printed reference observations in this pinned collection.
These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.
Why these observations are shown
They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.
Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 060ea9e229fbbe0b3a9a0ac08d0f2f432760573f13346f8f9cbc6a95c7626d82. Source manifest: a8e359fdb80cf1f79d6014a85397fcaae5a4e8668d053c20bb1f24945e329b23.
Official source · 2004-11-26
Publication text
This is the complete recorded text of this dated publication.
Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.
Read the complete official publication text
[Federal Register Volume 69, Number 227 (Friday, November 26, 2004)]
[Rules and Regulations]
[Pages 68769-68771]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-25791]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-NE-23-AD; Amendment 39-13880; AD 2004-24-04]
RIN 2120-AA64
Airworthiness Directives; Rolls-Royce Corporation (Formerly
Allison Engine Company, Allison Gas Turbine Division, and Detroit
Diesel Allison) (RRC) Models 250-C30R/3, -C30R/3M, -C47B, and -C47M
Turboshaft Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is superseding an existing airworthiness directive
(AD) for RRC models 250-C30R/3, -C30R/3M, -C47B, and -C47M turboshaft
engines. That AD currently requires initial and repetitive electrical
signal inspections of the hydromechanical unit (HMU) Power Lever Angle
(PLA) potentiometer. This ad continues to require those inspections and
adds replacement of the existing HMU with a new design HMU as a
mandatory terminating action to the repetitive inspection requirements.
This AD results from the manufacturer releasing a redesigned HMU that
has a dual-element potentiometer. We are issuing this AD to prevent
uncommanded and sudden changes in engine power.
DATES: This AD becomes effective January 3, 2005. The Director of the
Federal Register approved the incorporation by reference of certain
publications listed in the regulations as of January 3, 2005.
ADDRESSES: You can get the service information identified in this AD
from Rolls-Royce Corporation, P.O. Box 420, Indianapolis, IN 46206-
0420; telephone (317) 230-6400; fax (317) 230-4243.
You may examine the AD docket at the FAA, New England Region,
Office of the Regional Counsel, 12 New England Executive Park,
Burlington, MA. You may examine the service information, at the FAA,
New England Region, Office of the Regional Counsel, 12 New England
Executive Park, Burlington, MA; or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.
FOR FURTHER INFORMATION CONTACT: Khailaa Hosny, Aerospace Engineer,
Chicago Aircraft Certification Office, FAA, 2300 East Devon Avenue, Des
Plaines, IL 60018-4696; telephone (847) 294-7134; fax (847) 294-7834.
SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39
with a proposed AD. The proposed AD applies to RRC models 250-C30R/3, -
C30R/3M, -C47B, and -C47M turboshaft engines. We published the proposed
AD in the Federal Register on June 9, 2004 (69 FR 32287). That action
proposed to require initial and repetitive electrical signal
inspections of the HMU PLA potentiometer and replacement of the
existing HMU with a new design HMU as a mandatory terminating action to
the repetitive inspection requirements.
Examining the AD Docket
You may examine the AD Docket (including any comments and service
information), by appointment, between 8 a.m. and 4:30 p.m., Monday
through Friday, except Federal holidays. See ADDRESSES for the
location.
Comments
We provided the public the opportunity to participate in the
development of this AD. We received no comments on the proposal or on
the determination of the cost to the public.
Conclusion
We have carefully reviewed the available data and determined that
air safety and the public interest require adopting the AD as proposed.
Costs of Compliance
We estimate that 700 engines installed on helicopters of U.S.
registry will be affected by this AD. We estimate that it will take
about 4 work hours per engine to replace a single-element HMU with a
dual-element HMU. We also estimate that 12 percent of the single-
element HMUs will fail the required inspection and require replacing
the HMU. The average labor rate is $65 per work hour. Required parts
cost about $615 per engine. Based on these figures, we estimate the
total cost of the AD to U.S. operators to be $686,000.
[[Page 68770]]
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will not have a
substantial direct effect on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866;
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979); and
(3) Will not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
We prepared a summary of the costs to comply with this AD and
placed it in the AD Docket. You may get a copy of this summary by
sending a request to us at the address listed under ADDRESSES. Include
``AD Docket No. 2003-NE-23-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
Accordingly, under the authority delegated to me by the Administrator,
the Federal Aviation Administration amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
0
2. The FAA amends Sec. 39.13 by removing Amendment 39-13210 (68 FR
38590, June 30, 2003) and by adding a new airworthiness directive,
Amendment 39-13880, to read as follows:
2004-24-04 Rolls-Royce Corporation (formerly Allison Engine Company,
Allison Gas Turbine Division, and Detroit Diesel Allison): Amendment
39-13880. Docket No. 2003-NE-23-AD. Supersedes AD 2003-13-10,
Amendment 39-13210.
Effective Date
(a) This AD becomes effective January 3, 2005.
Affected ADs
(b) This AD supersedes AD 2003-13-10.
Applicability
(c) This AD applies to Rolls-Royce Corporation (formerly Allison
Engine Company, Allison Gas Turbine Division, and Detroit Diesel
Allison) (RRC) models 250-C30R/3, -C30R/3M, -C47B, and -C47M
turboshaft engines that have a hydromechanical unit (HMU) with a
part number (P/N) listed in 1.A. Group A of RRC Alert Commercial
Engine Bulletins (ACEB) No. CEB A-73-3103, Revision 4, dated
December 2, 2003; and No. CEB A-73-6030, Revision 4, dated December
2, 2003. These engines are installed on, but not limited to, Bell
OH-58D, Bell Helicopter Textron 407, Boeing AH/MH-6M, and MD
Helicopters Inc. 600N helicopters.
Unsafe Condition
(d) This AD results from the manufacturer releasing a redesigned
HMU that has a dual-element potentiometer. The actions specified in
this AD are intended to prevent uncommanded and sudden changes in
engine power.
Compliance
(e) Compliance with this AD is required as indicated, unless
already done.
Initial Inspection
(f) Perform an initial electrical signal inspection of the HMU
Power Lever Angle (PLA) potentiometer, within 300 flight hours (FH)
after the effective date of this AD. Use paragraphs 2.B. through
2.B.(8) and 2.B.(10) of the Accomplishment Instructions of RRC ACEB
No. CEB A-73-3103, Revision 4, dated December 2, 2003; or No. CEB A-
73-6030, Revision 4, dated December 2, 2003; to perform the
inspection.
(g) Replace the HMU before further flight if the electrical
signal inspection result is unacceptable.
Repetitive Inspections
(h) Thereafter, perform repetitive electrical signal inspections
of the HMU PLA potentiometer within 300 FH of the last inspection.
Use paragraphs 2.B. through 2.B.(8) and 2.B.(10) of the
Accomplishment Instructions of RRC ACEB No. CEB A-73-3103, Revision
4, dated December 2, 2003; or No. CEB A-73-6030, Revision 4, dated
December 2, 2003; to perform the inspection.
(i) Replace the HMU before further flight if the electrical
signal inspection result is unacceptable.
Mandatory Terminating Action
(j) Replace the HMU with an HMU that has a P/N not specified in
this AD within 600 FH after the effective date of this AD, or
January 31, 2005, whichever occurs earlier. Replacing the HMU with
an HMU that has a P/N not specified in this AD terminates the
repetitive inspection requirement specified in paragraph (h) of this
AD.
Alternative Methods of Compliance
(k) Alternative methods of compliance must be requested in
accordance with 14 CFR part 39.19, and must be approved by the
Manager, Chicago Aircraft Certification Office, FAA.
Material Incorporated by Reference
(l) You must use the Rolls-Royce Corporation Alert Commercial
Engine Bulletins (ACEBs) listed in Table 1 of this AD to perform the
inspections required by this AD. The Director of the Federal
Register approved the incorporation by reference of the documents
listed in Table 1 of this AD in accordance with 5 U.S.C. 552(a) and
1 CFR part 51. You can get a copy from Rolls-Royce Corporation, P.O.
Box 420, Indianapolis, IN 46206-0420; telephone (317) 230-6400; fax
(317) 230-4243. You can review copies at the FAA, New England
Region, Office of the Regional Counsel, 12 New England Executive
Park, Burlington, MA; or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. Table 1 follows:
Table 1.--Incorporation by Reference
----------------------------------------------------------------------------------------------------------------
Page number(s) shown Revision level shown
Service bulletin on the page on the page Date shown on the page
----------------------------------------------------------------------------------------------------------------
CEB A-73-3103, Total Pages: 20.... All................. 4.................... December 2, 2003.
CEB A-73-6030, Total Pages: 20.... All................. 4.................... December 2, 2003.
----------------------------------------------------------------------------------------------------------------
[[Page 68771]]
Related Information
(m) None.
Issued in Burlington, Massachusetts, on November 15, 2004.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification
Service.
[FR Doc. 04-25791 Filed 11-24-04; 8:45 am]
BILLING CODE 4910-13-P
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- Text SHA-256
- 060ea9e229fbbe0b3a9a0ac08d0f2f432760573f13346f8f9cbc6a95c7626d82
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These are dated publication metadata, recorded clauses and literal source observations. Word, model-label, header and reference matches do not establish current legal effect, manufacturer/model identity, aircraft applicability, installed configuration or compliance.
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