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[Federal Register: May 12, 2010 (Volume 75, Number 91)]
[Proposed Rules]               
[Page 26681-26683]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12my10-14]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28077; Directorate Identifier 2007-NE-20-AD]
RIN 2120-AA64

 
Airworthiness Directives; Turbomeca S.A. Arriel 2B and 2B1 
Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to revise an existing airworthiness directive (AD) 
for the products listed above. This proposed AD results from mandatory 
continuing airworthiness information (MCAI) issued by an aviation 
authority of another country to identify and correct an unsafe 
condition on an aviation product. The MCAI describes the unsafe 
condition as: Since issuance of AD 2007-0109, Turbom[eacute]ca has 
released modification TU166 which consists in inserting HP blade 
dampers between the HP disc and the HP blade platform. Introduction of 
these dampers has demonstrated to limit axial displacement of the HP 
blade relative to the disk in case of blade lock rupture or opening, 
therefore eliminating the need for inspection and replacement.
    We are proposing this AD to prevent an uncommanded in-flight engine 
shutdown which could result in an emergency autorotation landing or an 
accident.

DATES: We must receive comments on this proposed AD by June 28, 2010.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 1200 New Jersey Avenue, SE., West Building Ground 
Floor, Room W12-140, Washington, DC 20590-0001.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
     Fax: (202) 493-2251.
    Contact Turbomeca, 40220 Tarnos, France; telephone 33 05 59 74 40 
00, fax 33 05 59 74 45 15 for the service information identified in 
this proposed AD.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office 
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 Operations office (telephone (800) 647-5527) is 
the same as the Mail address provided in

[[Page 26682]]

the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Kevin Dickert, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; e-mail: 
kevin.dickert@faa.gov; telephone (781) 238-7117, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2007-
28077; Directorate Identifier 2007-NE-20-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 based on 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 
with FAA personnel concerning this proposed AD. Using the search 
function of the Web site, anyone can find and read the comments in any 
of our dockets, including, if provided, 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).

Discussion

    On April 16, 2009, the FAA issued AD 2009-09-03, Amendment 39-15889 
(74 FR 18981, April 27, 2009). That AD requires performing an initial 
and repetitive borescope inspection of the engine for rearward 
displacement of the high-pressure turbine (HP) blades.

Actions Since AD 2009-09-03 Was Issued

    Since that AD was issued, the European Aviation Safety Agency 
(EASA), which is the Technical Agent for the Member States of the 
European Community, has issued EASA Airworthiness Directive 2007-
0109R1, dated November 9, 2009 (referred to after this as ``the 
MCAI''), to correct an unsafe condition for the specified products. The 
MCAI states:

    Since issuance of AD 2007-0109, Turbom[eacute]ca has released 
modification TU166 which consists in inserting HP blade dampers 
between the HP disc and the HP blade platform. Introduction of these 
dampers has demonstrated to limit axial displacement of the HP blade 
relative to the disk in case of blade lock rupture or opening, 
therefore eliminating the need for inspection and replacement.
    Therefore, this AD revises AD 2007-0109 by retaining the same 
requirements of AD 2007-0109 except that applicability is limited to 
ARRIEL 2B, 2B1 and 2B1A engines which do not incorporate 
modification TU166.

You may obtain further information by examining the MCAI in the AD 
docket.

Relevant Service Information

    Turbomeca S.A. has issued Mandatory Service Bulletin No. 292 72 
2825, Version B, dated September 21, 2009. The actions described in 
this service information are intended to correct the unsafe condition 
identified in the EASA AD.

FAA's Determination and Requirements of This Proposed AD

    This product has been approved by the aviation authority of France, 
and is approved for operation in the United States. Pursuant to our 
bilateral agreement with France, they have notified us of the unsafe 
condition described in the EASA AD and service information referenced 
above. We are proposing this AD because we evaluated all information 
provided by EASA, and determined the unsafe condition exists and is 
likely to exist or develop on other products of the same type design. 
This proposed AD would require inspecting for HP blade rearward 
displacement.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we required different actions 
in this AD from those in the MCAI in order to follow FAA policies. Any 
such differences are described in a separate paragraph of the AD. These 
requirements take precedence over the actions copied from the MCAI.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 248 products of U.S. registry. We also estimate that 
it would take about 2 work-hours per product to comply with this 
proposed AD. The average labor rate is $85 per work-hour. Based on 
these figures, we estimate the cost of the proposed AD on U.S. 
operators to be $42,160.

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); 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 regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket.

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:

[[Page 26683]]

    Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13  [Amended]

    2. The FAA amends Sec.  39.13 by removing Amendment 39-15889 and 
adding the following new AD:

Turbomeca S.A.: Docket No. FAA-2007-28077; Directorate Identifier 
2007-NE-20-AD.

Comments Due Date

    (a) We must receive comments by June 28, 2010.

Affected Airworthiness Directives (ADs)

    (b) This AD revises AD 2009-09-03, Amendment 39-15889.

Applicability

    (c) This AD applies to Turbomeca S.A. Arriel 2B and 2B1 
turboshaft engines that don't incorporate modification TU166. These 
engines are installed on, but not limited to, Eurocopter AS 350 B3 
and EC 130 B4 helicopters.

Reason

    (d) This AD results from:

    Since issuance of AD 2007-0109, Turbom[eacute]ca has released 
modification TU166 which consists in inserting HP blade dampers 
between the HP disc and the HP blade platform. Introduction of these 
dampers has demonstrated to limit axial displacement of the HP blade 
relative to the disk in case of blade lock rupture or opening, 
therefore eliminating the need for inspection and replacement.

We are issuing this AD to prevent an uncommanded in-flight engine 
shutdown which could result in an emergency autorotation landing or 
an accident.

Actions and Compliance

    (e) Unless already done, do the following actions:

Initial Inspection

    (1) Perform an initial high-pressure (HP) turbine borescope 
inspection according to Turbomeca S.A. Mandatory Service Bulletin 
(MSB) No. 292 72 2825, Version B, dated September 21, 2009, or 
earlier version as follows:
    (i) For engines with fewer than 500 hours and 450 cycles since 
new or since the last HP turbine borescope inspection, inspect 
before reaching 600 hours or 500 cycles whichever occurs first. 
Replace HP turbine modules with rearward turbine blade displacement 
greater than 0.5 mm.
    (ii) For the remaining engines, inspect within the next 100 
hours. Replace HP turbine modules with rearward turbine blade 
displacement greater than 0.5 mm.

Repetitive Inspections

    (2) Perform repetitive HP turbine borescope inspections 
according to Turbomeca S.A. MSB No. 292 72 2825, Version B, dated 
September 21, 2009 or earlier version:
    (i) Within 600 hours or 500 cycles from the previous inspection, 
whichever occurs first, if the rearward displacement of the turbine 
blades was less than 0.2 mm. Replace HP turbine modules with 
rearward turbine blade displacement greater than 0.5 mm.
    (ii) Within 100 hours of the previous inspection if the rearward 
displacement of the turbine blades was between 0.2 mm and 0.5 mm. 
Replace HP turbine modules with rearward turbine blade displacement 
greater than 0.5 mm.

Optional Terminating Action

    (f) Incorporating modification TU166 terminates the repetitive 
inspection requirements of paragraphs (e)(2)(i) and (e)(2)(ii) of 
this AD.

FAA AD Differences

    (g) For clarification, we restructured the actions and 
compliance wording of this AD.
    (h) We deleted the Turbomeca reporting requirement from the AD.
    (i) Although EASA Airworthiness Directive 2007-0109R1, dated 
November 9, 2009, applies to the Arriel 2B1A engine, this AD does 
not apply to that model because it has no U.S. type certificate.

Alternative Methods of Compliance (AMOCs)

    (j) The Manager, Engine Certification Office, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19.

Related Information

    (k) Refer to EASA Airworthiness Directive 2007-0109R1, dated 
November 9, 2009, and Turbomeca S.A. MSB No. 292 72 2825, Version B, 
dated September 21, 2009, or earlier version, for related 
information.
    (l) Contact Kevin Dickert, Aerospace Engineer, Engine 
Certification Office, FAA, Engine and Propeller Directorate, 12 New 
England Executive Park, Burlington, MA 01803; e-mail: 
kevin.dickert@faa.gov; telephone (781) 238-7117, fax (781) 238-7199.

    Issued in Burlington, Massachusetts, on May 5, 2010.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.

[FR Doc. 2010-11324 Filed 5-11-10; 8:45 am]
BILLING CODE 4910-13-P
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