AD 2005-22-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Rolls-Royce Corporation | 501-D22A | Airworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G Turboprop Engines |
| engine | Rolls-Royce Corporation | 501-D22C | Airworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G Turboprop Engines |
| engine | Rolls-Royce Corporation | 501-D22G | Airworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G Turboprop Engines |
Unsafe Condition
Improper metal hardness of certain 1st stage, 2nd stage, 3rd stage, and 4th stage turbine wheels can lead to over dimensional limits, potentially causing uncontained turbine wheel failure, damage to the airplane, and total loss of engine power.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the metal hardness of specified turbine wheels. Report findings within 30 days of inspection using specified procedures. Install a serviceable turbine wheel if necessary.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before 7,400 cycles-since-new of any 1st stage, 2nd stage, 3rd stage, or 4th stage turbine wheel.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Rolls-Royce Corporation (formerly Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G turboprop engines.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for Rolls-Royce Corporation (RRC) (formerly Allison Engine Company) 501- D22A, 501-D22C, and 501-D22G turboprop engines. This AD requires a onetime inspection for proper metal hardness of certain 1st stage, 2nd stage, 3rd stage, and 4th stage turbine wheels. This AD results from a report of a turbine wheel found to be over dimensional limits, caused by improper metal hardness. We are issuing this AD to prevent uncontained turbine wheel failure, leading to damage of the airplane and total loss of engine power.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 70, Number 205 (Tuesday, October 25, 2005)]
[Rules and Regulations]
[Pages 61549-61552]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 05-21173]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-20742; Directorate Identifier 2005-NE-03-AD;
Amendment 39-14347; AD 2005-22-03]
RIN 2120-AA64
Airworthiness Directives; Rolls-Royce Corporation (Formerly
Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G Turboprop
Engines
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
Rolls-Royce Corporation (RRC) (formerly Allison Engine Company) 501-
D22A, 501-D22C, and 501-D22G turboprop engines. This AD requires a
onetime inspection for proper metal hardness of certain 1st stage, 2nd
stage, 3rd stage, and 4th stage turbine wheels. This AD results from a
report of a turbine wheel found to be over dimensional limits, caused
by improper metal hardness. We are issuing this AD to prevent
uncontained turbine wheel failure, leading to damage of the airplane
and total loss of engine power.
DATES: This AD becomes effective November 29, 2005. The Director of the
Federal Register approved the incorporation by reference of certain
publications listed in the regulations as of November 29, 2005.
ADDRESSES: Contact Rolls-Royce Corporation, P.O. Box 420, 2001 South
Tibbs Avenue, Indianapolis, IN 46206-0420; telephone (317) 230-2000;
fax (317) 230-4020 for the service information identified in this AD.
You may examine the AD docket on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>
or in Room PL-401 on the plaza level of the Nassif Building, 400
Seventh Street, SW., Washington, DC.
FOR FURTHER INFORMATION CONTACT: Michael Downs, Aerospace Engineer,
Chicago Aircraft Certification Office, FAA, 2300 East Devon Avenue, Des
Plaines, IL 60018; telephone (847) 294-7870; fax (847) 294-7834.
SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR part 39
with a proposed airworthiness directive (AD). The proposed AD applies
to Rolls-Royce Corporation (RRC) (formerly Allison Engine Company) 501-
D22A, 501-D22C, and 501-D22G turboprop engines. We published the
proposed AD in the Federal Register on March 29, 2005 (70 FR 15784).
That action proposed to require a onetime inspection for proper metal
hardness of certain 1st stage, 2nd stage, 3rd stage, and 4th stage
turbine wheels. That action proposed to do the inspection at the next
shop visit of the engine or turbine module, but not to exceed 7,400
cycles-since-new of any 1st stage, 2nd stage, 3rd stage, or 4th stage
turbine wheel.
Examining the AD Docket
You may examine the docket that contains the AD, any comments
received, and any final disposition in person at the Docket Management
Facility Docket Offices between 9 a.m.
[[Page 61550]]
and 5 p.m., Monday through Friday, except Federal holidays. The Docket
Office (telephone (800) 647-5227) is located on the plaza level of the
Department of Transportation Nassif Building at the street address
stated in ADDRESSES. Comments will be available in the AD docket
shortly after the DMS receives them.
Comments
We provided the public the opportunity to participate in the
development of this AD. We have considered the comments received.
NPRM Work Hour Estimate Is Different Than Estimate in RRC Commercial
Engine Bulletins
One commenter states that the NPRM work hour estimate of 0.5 hour
per engine is different from the estimate in the RRC Commercial Engine
Bulletins (CEBs) No. CEB-72-1138, No. CEB-72-4051, and No. CEB-72-1584,
(combined in one document) dated January 23, 2004. The CEBs state that
the 0.5 hour for inspection is in addition to the time required to
remove the wheel. The commenter received an estimate from a Rolls-
Royce-authorized overhaul facility of 250 work hours to perform the
wheel inspection, which includes turbine disassembly and reassembly. We
disagree. We estimated the cost of compliance to be 0.5 hour based on
the assumption that the turbine is disassembled for other reasons,
notably for an overhaul. The 250 work hours are basic and unrelated to
the onetime inspection required by this AD. We have clarified in this
final rule that the 0.5 hour is for the onetime inspection for metal
hardness, but we have not changed the total costs of compliance in the
AD.
Airplane Designations Not on the Type Certificate
The same commenter states that in the Applicability paragraph of
the proposed AD, the L-100-20 and L-100-30 airplane designations are
not included on the type certificate. The commenter suggests that only
the type certificated airplanes be listed. The commenter states that
historically, the L-382E is also known as the L-100-20, and the L-382G
is also known as the L-100-30. We agree. We have corrected the
Applicability in the AD to list the type-certificated airplanes and put
the other designations in parentheses, for reference.
The Term ``Shop Visit'' Needs Clarification
The same commenter states that in the Compliance paragraph of the
proposed AD, the term ``shop visit'' needs clarification. The commenter
asks if it is our intention to have the hardness test performed at the
next visit to the engine shop, regardless of the extent of other work
performed. The commenter feels that is not our intention. The commenter
also cites the recommended compliance appearing in CEBs No. CEB-72-
1138, No. CEB-72-4051, and No. CEB-72-1584, (combined in one document)
dated January 23, 2004. The commenter suggests that the Compliance
paragraph be changed to require compliance with the hardness inspection
on suspect turbine wheels based on whichever of the following events
occurs first:
<bullet> Not to exceed 7,400 cycles-since-new;
<bullet> Before installation of a suspect turbine wheel onto the
rotor;
<bullet> When the suspect turbine wheel is next accessed by rotor
disassembly.
We disagree. We expect a ``shop visit'' to be a visit that results
in a turbine wheel disassembly. The most common term is overhaul, but
not all users request an overhaul from their supplier when a turbine
module visits the shop. The type of service being sought is not
relevant to the hardness inspection. What is relevant, is that you
perform the inspection before 7,400 cycles-since-new. We have not
changed the Compliance paragraph in the AD based on this comment.
Request To Clarify Where To Mark the Part
The same commenter requests that we change compliance paragraph (h)
to allow the part to be marked after or near the end of the serial
number. The commenter states that CEBs No. CEB-72-1138, No. CEB-72-
4051, and No. CEB-72-1584, (combined in one document) dated January 23,
2004, also specify the marking this way. The paragraph in the proposed
AD instructs service personnel to mark the part after the serial number
only. The commenter states there is not always adequate space to mark
the part after the serial number. We disagree. The area suitable for
marking is quite large, however RRC chose to use the words ``after or
near'' to make sure the part is marked in a suitable place. We have not
changed the AD based on this comment.
Request Clarification of When To Report Findings of Inspections
The same commenter requests clarification of when to report
findings of inspections. The proposed AD requires reporting findings of
inspections using the procedures specified in paragraph 2.E. of RRC
CEBs No. CEB-72-1138, No. CEB-72-4051, and No. CEB-72-1584, (combined
in one document) dated January 23, 2004. Those procedures state that
inspection results be reported to Rolls-Royce T56/501 Customer Support
in compliance with this CEB (when done). ``When done'' does not specify
a time frame for submitting the inspection results. Some people may
interpret this as immediately and others at a later time. The commenter
suggests we specify that the inspection findings be submitted within 30
days of the inspection completion. We agree. We have changed paragraph
(i) of the AD to state to report findings of inspections within 30 days
of inspection using the procedures specified in paragraph 2.E of RRC
CEBs No. CEB-72-1138, No. CEB-72-4051, and No. CEB-72-1584, (combined
in one document) dated January 23, 2004.
Clarification of Compliance
As clarification, we have added wording to paragraph (g) of this
AD, to state to install a serviceable turbine wheel. This change
relates the compliance to the serviceable turbine wheel definition in
paragraph (j) of this AD.
Conclusion
We have carefully reviewed the available data, including the
comments received, and determined that air safety and the public
interest require adopting the AD with the changes described previously.
We have determined that these changes will neither increase the
economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
There are about 150 RRC 501-D22A, 501-D22C, and 501-D22G turboprop
engines of the affected design in the worldwide fleet. We estimate that
150 engines installed on airplanes of U.S. registry are affected by
this AD. We also estimate that it will take about 0.5 work hour per
engine to perform the onetime inspection for proper metal hardness, and
that the average labor rate is $65 per work hour. Required parts will
cost about $1,495 per turbine wheel. The manufacturer has stated that
it may provide replacement parts for turbine wheels that do not meet
inspection criteria, at no cost to operators. Based on these figures,
we estimate the total cost of the AD to U.S. operators to be $229,125.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, Section 106, describes the
authority of
[[Page 61551]]
the FAA Administrator. Subtitle VII, Aviation Programs, describes in
more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701, ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
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 at the
address listed under ADDRESSES.
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 adding the following new airworthiness
directive:
2005-22-03 Rolls-Royce Corporation (formerly Allison Engine
Company): Amendment 39-14347. Docket No. FAA-2005-20742; Directorate
Identifier 2005-NE-03-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective November
29, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Rolls-Royce Corporation (RRC) (formerly
Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G turboprop
engines with the turbine wheels listed in the following Table 1,
installed.
Table 1.--Affected Turbine Wheels
----------------------------------------------------------------------------------------------------------------
Turbine wheel part number Turbine wheel Serial numbers
----------------------------------------------------------------------------------------------------------------
6875431............................. 1st Stage.............. KK50152 through KK50199.
6845592............................. 2nd Stage.............. KK40998 through KK41057.
6845593............................. 3rd Stage.............. KK36452 through KK36461, and KK36492 through
KK36532.
6870434............................. 4th Stage.............. KK40320 through KK40393, and KK40485 through
KK40535.
----------------------------------------------------------------------------------------------------------------
These engines are installed on, but not limited to, Commercial
Hercules L-382B, L-382E (L-100-20), L-382G (L-100-30), Airbus Super
Guppy-201, Super Convair CV-580A, and CV5800 airplanes.
Unsafe Condition
(d) This AD results from a report of a turbine wheel found to be
over dimensional limits, caused by improper metal hardness. We are
issuing this AD to prevent uncontained turbine wheel failure,
leading to damage of the airplane and total loss of engine power.
Compliance
(e) You are responsible for having the actions required by this
AD performed at the next shop visit of the engine or turbine module,
but not to exceed 7,400 cycles-since-new of any 1st stage, 2nd
stage, 3rd stage, or 4th stage turbine wheel, unless the actions
have already been done.
Onetime Inspection for Proper Metal Hardness
(f) Perform a onetime inspection for proper metal hardness of
1st stage, 2nd stage, 3rd stage, and 4th stage turbine wheels. Use
paragraphs 2.B. and 2.F. of RRC Commercial Engine Bulletins (CEBs)
No. CEB-72-1138, No. CEB-72-4051, and No. CEB-72-1584, (combined in
one document) dated January 23, 2004.
(g) Remove from service any turbine wheel that does not pass
inspection, using paragraph 2.C. of RRC CEBs No. CEB-72-1138, No.
CEB-72-4051, and No. CEB-72-1584, (combined in one document) dated
January 23, 2004, and install a serviceable turbine wheel.
(h) Mark the letters, HC, after the serial number on any turbine
wheel that passes inspection, using the method described in
paragraph 2.D. of RRC CEBs No. CEB-72-1138, No. CEB-72-4051, and No.
CEB-72-1584, (combined in one document) dated January 23, 2004.
Reporting Requirements
(i) Report findings of inspections within 30 days of inspection
using the procedures specified in paragraph 2.E of RRC CEBs No. CEB-
72-1138, No. CEB-72-4051, and No. CEB-72-1584, (combined in one
document) dated January 23, 2004. The Office of Management and
Budget (OMB) has approved the reporting requirements specified in
paragraph 2.E. of RRC CEBs No. CEB-72-1138, No. CEB-72-4051, and No.
CEB-72-1584, (combined in one document) dated January 23, 2004, and
assigned OMB control number 2120-0056.
Definition
(j) For the purpose of this AD, a serviceable turbine wheel is:
(1) A turbine wheel that has a serial number not listed in this
AD; and
(2) A turbine wheel that has a serial number listed in this AD
that passed the inspection specified in paragraph (f) of this AD.
Alternative Methods of Compliance
(k) The Manager, Chicago Aircraft Certification Office, has the
authority to approve alternative methods of compliance for this AD
if requested using the procedures found in 14 CFR 39.19.
Related Information
(l) None.
Material Incorporated by Reference
(m) You must use Rolls-Royce Corporation Commercial Engine
Bulletins No. CEB-72-1138, No. CEB-72-4051, and No. CEB-72-1584,
(combined in one document) dated January 23, 2004, to perform the
actions
[[Page 61552]]
required by this AD. The Director of the Federal Register approved
the incorporation by reference of this service bulletin in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Rolls-
Royce Corporation, P.O. Box 420, 2001 South Tibbs Avenue,
Indianapolis, IN 46206-0420; telephone (317) 230-2000; fax (317)
230-4020 for a copy of this service information. You may review
copies at the Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-
401, Washington, DC 20590-0001, on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>, 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: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Burlington, Massachusetts, on October 17, 2005.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 05-21173 Filed 10-24-05; 8:45 am]
BILLING CODE 4910-13-P
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