[Federal Register Volume 70, Number 190 (Monday, October 3, 2005)]
[Rules and Regulations]
[Pages 57487-57491]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-19693]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22534; Directorate Identifier 2005-NE-27-AD; 
Amendment 39-14305; AD 2005-20-11]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce Corporation (RRC) (formerly 
Allison Engine Company, Allison Gas Turbine Division, and Detroit 
Diesel Allison) Models 250-C28, -C28B, and -C28C Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

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ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
Rolls-Royce Corporation (formerly Allison Engine Company, Allison Gas 
Turbine Division, and Detroit Diesel Allison) (RRC) Models 250-C28, -
C28B, and -C28C turboshaft engines. This AD requires a onetime visual 
inspection of the seal joint in each passage between airfoils at the 
hub and shroud of third-stage turbine wheels, part number (P/N) 
6899383. This AD results from reports of three failed third-stage 
turbine wheels and from the manufacturer's analysis of those failures. 
We are issuing this AD to prevent loss of power and uncommanded engine 
shutdown due to failure of the third-stage turbine wheel.

DATES: This AD becomes effective October 18, 2005.
    We must receive any comments on this AD by December 2, 2005.

ADDRESSES: Use one of the following addresses to comment on this AD:
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590-0001.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Rolls-Royce Corporation, PO Box 420, Indianapolis, IN 
46206-0420; telephone (317) 230-6400; fax (317) 230-4243 for the 
service information identified in this AD.

FOR FURTHER INFORMATION CONTACT: John Tallarovic, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, 2300 East Devon Avenue, Des 
Plaines, IL 60018-4696; telephone (847) 294-8180; fax (847) 294-7834.

SUPPLEMENTARY INFORMATION: In April 2005, we became aware of reports of 
three failed third-stage turbine wheels, P/N 6899383. The third-stage 
turbine wheels had partial loss of the blades and shroud. RRC conducted 
an analysis and found the failures were caused by compromised third-
stage blade fillet radii, which led to increased stresses to the third-
stage blades and shroud. RRC categorized this finding as a 
manufacturer's quality control problem. This condition, if not 
corrected, could result in loss of power and uncommanded engine 
shutdown due to failure of the third-stage turbine wheel.

FAA's Determination and Requirements of This AD

    The unsafe condition described previously is likely to exist or 
develop on other RRC Models 250-C28, -C28B, and -C28C turboshaft 
engines of the same type design. For that reason, we are issuing this 
AD to prevent loss of power and uncommanded engine shutdown due to 
failure of the third-stage turbine wheel. This AD requires a onetime 
visual inspection of the seal joint in each passage between airfoils at 
the hub and shroud of third-stage turbine wheels, P/N 6899383.

FAA's Determination of the Effective Date

    Since an unsafe condition exists that requires the immediate 
adoption of this AD, we have found that notice and opportunity for 
public comment before issuing this AD are impracticable, and that good 
cause exists for making this amendment effective in less than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety and was not preceded by notice and an opportunity for public 
comment; however, we invite you to send us any written relevant data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. FAA-2005-22534; 
Directorate Identifier 2005-NE-27-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify it.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this AD. Using the search function of the Docket 
Management System (DMS) Web site, anyone can find and read the comments 
in any of our dockets, including the name of the individual who sent 
the comment (or signed the comment on behalf of an association, 
business, labor union, etc.). You may review the DOT's complete Privacy 
Act Statement in the Federal Register published on April 11, 2000 (65 
FR 19477-78) or you may visit http://dms.dot.gov.

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. 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.

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 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 the regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the 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.

[[Page 57489]]

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration amends part 39 of the Federal Aviation 
Regulations (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:

2005-20-11 Rolls-Royce Corporation (formerly Allison Engine Company, 
Allison Gas Turbine Division, and Detroit Diesel Allison): Amendment 
39-14305. Docket No. FAA-2005-22534; Directorate Identifier 2005-NE-
27-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective October 
18, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Rolls-Royce Corporation (RRC) (formerly 
Allison Engine Company, Allison Gas Turbine Division, and Detroit 
Diesel Allison) models 250-C28, -C28B, and -C28C turboshaft engines. 
These engines are installed on, but not limited to, Bell Helicopter 
Textron 206L-1; Eurocopter Deutschland BO 105 LS A-1; and Eurocopter 
Canada BO 105 LS A-3 helicopters.

Unsafe Condition

    (d) This AD results from reports of three failed third-stage 
turbine wheels and from the manufacturer's analysis of those 
failures. We are issuing this AD to prevent loss of power and 
uncommanded engine shutdown due to failure of the third-stage 
turbine wheel.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified unless the 
actions have already been done.

Onetime Visual Inspection

    (f) For third-stage turbine wheels, part number (P/N) 6899383, 
with fewer than 3,000 hours time-since-new (TSN), inspect the next 
time the third-stage turbine wheel is directly available for 
removal, at the next turbine overhaul, or by April 30, 2007, 
whichever occurs sooner.
    (g) For third-stage turbine wheels, P/N 6899383, with 3,000 
hours or more TSN, inspect within 300 hours or by April 30, 2007, 
whichever occurs sooner.
    (h) Remove the third-stage turbine wheel and perform a onetime 
visual inspection of the seal joint in each passage between airfoils 
at the hub and shroud. Seal joint evidence must not be present 
within blade fillet radii. See Figure 1 of this AD for reference.
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    (i) Remove from service any turbine wheel that has seal joint 
evidence present within blade fillet radii.

Alternative Methods of Compliance

    (j) 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

    (k) RRC Alert Service Bulletin No. CEB-A-72-2205, dated April 
26, 2005, pertains to the subject of this AD.

    Issued in Burlington, Massachusetts, on September 26, 2005.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-19693 Filed 9-30-05; 8:45 am]
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