Document ID: FAA-2011-0961-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce Corporation Turboshaft Engines
Posted Date: 2011-12-20T05:00Z

[Federal Register Volume 76, Number 244 (Tuesday, December 20, 2011)]
[Proposed Rules]
[Pages 78863-78864]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-32491]

 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 76, No. 244 / Tuesday, December 20, 2011 / 
Proposed Rules  

[[Page 78863]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0961; Directorate Identifier 2011-NE-22-AD]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce Corporation Turboshaft 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
certain Rolls-Royce Corporation (RRC) 250-C20, -C20B, and -C20R/2 
turboshaft engines. This proposed AD was prompted by seven cases 
reported of released turbine blades and shrouds, which led to loss of 
power and engine in-flight shutdowns (IFSDs). This proposed AD would 
require a one-time visual inspection and fluorescent penetrant 
inspection (FPI) on certain 3rd and 4th stage turbine wheels for cracks 
in the turbine blades. We are proposing this AD to prevent failure of 
3rd or 4th stage turbine wheel blades which could cause engine failure 
and damage to the airplane.

DATES: We must receive comments on this proposed AD by February 21, 
2012.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, contact Rolls-
Royce Corporation Customer Support, P.O. Box 420, Indianapolis, IN 
46206-0420; phone: (888) 255-4766 or (317) 230-2720; fax: (317) 230-
3381, email: royce.com">helicoptercustsupp@rolls-royce.com, and Web site: 
www.rolls-royce.com. You may review copies of the referenced service 
information at the FAA, Engine & Propeller Directorate, 12 New England 
Executive Park, Burlington, MA 01803. For information on the 
availability of this material at the FAA, call (781) 238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: John Tallarovic, Aerospace Engineer, 
Chicago Aircraft Certification Office, FAA, 2300 E. Devon Ave., Des 
Plaines, IL 60018; phone: (847) 294-8180; fax: (847) 294-7834; email: 
john.m.tallarovic@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2011-0961; 
Directorate Identifier 2011-NE-22-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We received reports of seven cases of released turbine blades and 
shrouds due to fatigue on certain RRC 250-C20, -C20B, and -C20R/2 
turboshaft engines. These cases resulted in loss of power and engine 
IFSDs. This condition, if not corrected, could result in IFSDs. We are 
proposing a one-time visual and FPI on the 3rd stage turbine wheel, 
part number (P/N) 23065818, and on the 4th stage turbine wheel, P/N 
23055944.
    Since the original approval of these parts, speed avoidance 
restrictions have been established for these engines to prevent fatigue 
damage. In trying to identify the cause of this failure, RRC conducted 
an extensive product review. This product review determined the cause 
of the problem and instituted corrective actions. However, latent 
damage may still be present. Therefore, this unsafe condition may still 
exist.

Relevant Service Information

    We reviewed RRC Alert Commercial Engine Bulletin (CEB) No. CEB-A-
1407, Revision 1, dated February 7, 2011 and CEB-A-72-4098, Revision 1, 
dated February 7, 2011 (combined in one document). Alert CEB-A-1407 
describes procedures for performing a one-time visual inspection and 
FPI on the 3rd stage turbine wheel, P/N 23065818, and on the 4th stage 
turbine wheel, P/N 23055944 for cracks in the turbine blades on the 
model 250-C20 and -C20B turboshaft engines. Alert CEB-A-72-4098 
describes procedures for performing a one-time visual inspection and 
FPI on the 3rd stage turbine wheel, P/N 23065818, and on the 4th stage 
turbine wheel, P/N 23055944 for cracks in the turbine blades on the 
model 250-C20R/2 turboshaft engine.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in the service information described previously.

[[Page 78864]]

Costs of Compliance

    We estimate that this proposed AD would affect 500 RRC C250-C20, -
C20B, and -C20R/2 turboshaft engines installed on aircraft of U.S. 
registry. We also estimate that it would take about 5 hours to perform 
a one-time visual inspection and FPI of the 3rd stage turbine wheel and 
the 4th stage turbine wheel for cracks in the turbine blades, for each 
engine. The average labor rate is $85 per work-hour. We anticipate no 
required parts cost. Based on these figures, we estimate the total cost 
of the AD to U.S. operators to be $212,500.

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 determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

    2. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

Rolls-Royce Corporation (Formerly Allison Engine Company and Allison 
Gas Turbine Division of General Motors): Docket No. FAA-2011-0961; 
Directorate Identifier 2011-NE-22-AD.

(a) Comments Due Date

    We must receive comments by February 21, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies only to Rolls-Royce Corporation 250-C20, -C20B, 
and -C20R/2 turboshaft engines with 3rd stage turbine wheel, part 
number (P/N) 23065818, and 4th stage turbine wheel, P/N 23055944.

(d) Unsafe Condition

    This AD was prompted by seven cases reported of released turbine 
blades and shrouds, which led to loss of power and engine in-flight 
shutdowns. We are issuing this AD to prevent failure of 3rd or 4th 
stage turbine wheel blades which could cause engine failure and 
damage to the airplane.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) Remove the 3rd stage turbine wheel, P/N 23065818, and the 
4th stage turbine wheel, P/N 23055944, at the next 1,750-hour 
overhaul.
    (2) Perform a one-time visual inspection and a fluorescent 
penetrant inspection on the 3rd and 4th stage turbine wheels for 
cracks at the trailing edge of the turbine blades near the fillet at 
the rim.
    (3) If any cracks in the trailing edge near the rim are 
detected, do not return the wheel to service.

(f) Alternative Methods of Compliance (AMOCs)

    The Manager, Chicago Aircraft Certification Office, FAA, may 
approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 
to make your request.

(g) Related Information

    (1) For more information about this AD, contact John Tallarovic, 
Aerospace Engineer, Chicago Aircraft Certification Office, FAA, 2300 
E. Devon Ave., Des Plaines, IL 60018; phone: (847) 294-8180; fax: 
(847) 294-7834; email: john.m.tallarovic@faa.gov.
    (2) Rolls-Royce Corporation Alert Commercial Engine Bulletin No. 
CEB-A-1407, Revision 1, dated February 7, 2011 and CEB-A-72-4098, 
Revision 1, dated February 7, 2011 (combined in one document) 
pertain to the subject of this AD.
    (3) For service information identified in this AD, contact 
Rolls-Royce Corporation Customer Support, P.O. Box 420, 
Indianapolis, IN 46206-0420; phone: (888) 255-4766 or (317) 230-
2720; fax: (317) 230-3381; email: royce.com">helicoptercustsupp@rolls-royce.com, and Web site: www.rolls-royce.com. You may review copies 
of the referenced service information at the FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803. 
For information on the availability of this material at the FAA, 
call (781) 238-7125.

    Issued in Burlington, Massachusetts, on December 14, 2011.
Thomas A. Boudreau,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-32491 Filed 12-19-11; 8:45 am]
BILLING CODE 4910-13-P