Airworthiness Directives; Rolls-Royce Corporation (Formerly Allison Engine Company) 501-D22A, 501-D22C, and 501-D22G Turboprop Engines

[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 [www.gpo.gov]
[FR Doc No: 05-21173]


-----------------------------------------------------------------------

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 http://dms.dot.gov 
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 http://dms.dot.gov, 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/cfr/ibr-locations.html.

    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

The complete text was extracted from the official GovInfo HTML edition for this publication. Acquired 2026-10-09T03:50:59.689881+00:00. Text extraction preserves the recorded source wording; it does not determine current requirements.

Open the captured official edition

Source SHA-256

32cf1bd41790122374d38c41f30372abc111bc02ad5552a9bc4c4ff995f8d0e8

Text SHA-256

9e70187ca477d745a5de77847d154954fee4868dc23ba9a2808eea899a5f60b3