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

ACTION: Final rule; request for comments.

SUMMARY: We are superseding an existing airworthiness directive (AD)
for the specified ECF model helicopters. This AD results from a
mandatory continuing airworthiness information (MCAI) AD issued by the
European Aviation Safety Agency (EASA), which is the Technical Agent
for the Member States of the European Union. The MCAI AD states that
some cracks have been discovered in the spar of the upper fin on Model
AS355N helicopters. Due to the fin design similarity between AS350 and
AS355 helicopters, this AD action applies to both helicopter models.
Modifying the upper and lower fin attachment is intended to prevent
failure of a spar, loss of a fin, a separated fin hitting a rotor, and
subsequent loss of control of a helicopter.

DATES: This AD becomes effective on February 8, 2012.
The incorporation by reference of certain publications is approved
by the Director of the Federal Register as of February 8, 2012.
We must receive comments on this AD by March 26, 2012.

ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the
instructions for submitting your comments electronically.
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: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
You may get the service information identified in this AD from
American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, TX
75053-4005, telephone (972) 641-3460, fax (972) 641-3527, or at http://www.eurocopter.com.
Examining The 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 AD, the economic evaluation, any
comments received, and other information. The street address for the
Docket Operations office (telephone (800) 647-5527) is stated in the
ADDRESSES section of this AD. Comments will be available in the AD
docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Jim Grigg, ASW-112, Aviation Safety
Engineer, Rotorcraft Directorate, Safety Management Group, 2601 Meacham
Blvd., Fort Worth, Texas 76137, telephone (817) 222-5126, fax (817)
222-5961.

SUPPLEMENTARY INFORMATION:

Discussion

On March 11, 1983, we issued AD 82-13-05 R1, Amendment 39-4567 (48
FR 13406, March 31, 1983), which revised AD 82-13-05, Amendment 39-4401
(47 FR 27244, June 24, 1982), which superseded AD 82-02-02, Amendment
39-4294 (47 FR 1113, January 11, 1982). The current AD requires a
visual check for a crack in the flanges of the upper vertical fin
support before the first flight each day. It also requires an initial
10 hours time-in-service (TIS) inspection and thereafter, at intervals
not to exceed 50 hours TIS, repetitive dye-penetrant or equivalent
inspections for a crack in the flange of the upper vertical fin
support. Since we issued those ADs, there have been additional reports
of cracks in the spar area of the upper tail fin of the ECF Model
AS355N helicopters.
EASA, which is the Technical Agent for the Member States of the
European Union, has issued EASA AD No. 2009-0030, dated February 12,
2009, which supersedes EASA AD 2008-0121, dated June 27, 2008, for the
AS350 helicopters. EASA has also issued AD No. 2009-0029, dated
February 12, 2009, which supersedes EASA AD 2008-0120, dated June 27,
2008, for the AS355 helicopters. This latest unsafe condition results
from additional cracks that have been discovered in the spar of the
upper fin on Model AS355N helicopters. Due to the fin design similarity
between AS350 and AS355 helicopters, the same corrective action applies
to both model helicopters. Modifying the upper and lower fin attachment
is intended to prevent failure of a spar, loss of a fin, a separated
fin hitting a rotor, and subsequent loss of control of a helicopter.
You may obtain further information by examining the MCAI and any
related service information in the AD docket.

Related Service Information

ECF has issued Alert Service Bulletin (ASB) No. 55.00.12, Revision
1, dated January 5, 2009, specifying MOD 073330 for the Model AS355E,
F, F1, F2, and N helicopters and No. 55.00.16, Revision 1, dated
January 5, 2009, specifying MOD 073330 for the Model SA350B, B1, B2,
B3, BA, BB, D, and L1 helicopters. ECF has also issued ASB No.
55.00.11, Revision 2, dated February 28, 2008, specifying MOD 073288
for the AS355 E, F, F1, F2, and N helicopters and No. 55.00.13,
Revision 2, dated February 28, 2008, specifying MOD 073288 for the
AS350B3 helicopters. These ASBs specify various inspections and
modifications for improving or monitoring upper and lower fin
attachments and improving the attachment strength for upper and lower
tailboom fin. The actions described in the MCAI AD are intended to
correct the same unsafe condition as that identified in the service
information.

FAA's Evaluation and Unsafe Condition Determination

These products have been approved by the aviation authority of
France and are approved for operation in the United States. Pursuant to
our bilateral agreement with France, EASA, their technical agent, has
notified us of the unsafe condition described in the MCAI AD. We are
issuing this AD because we evaluated all information provided by the
EASA and determined the unsafe condition exists and is likely to exist
or develop on other ECF helicopters of these same type designs.

Differences Between This AD and the MCAI

We refer to flight hours as hours time-in-service. The dates in the
MCAI have already passed; therefore, we did not use them in this AD.
Also, some of the requirements are out-of-date, and we have not
included them in this AD. We have also made some minor editorial
changes for clarity.

Costs of Compliance

We estimate that this AD will affect about 791 helicopters of U.S.
registry. We also estimate that it will take about 4 work-hours per
helicopter to modify the upper and lower fins and the upper and lower
fin attachments. The average labor rate is $85 per work-hour. Required
parts will cost about $453. Based on these figures, we estimate the
cost of this AD on U.S. operators will be $793 to modify each
helicopter or $627,263 for the fleet, assuming every helicopter is
modified.

FAA's Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of
this superseding AD. We find that the risk to the flying public
justifies waiving notice and comment prior to adoption of this rule
because of reported cracks in the spar of the upper fin on AS355N
helicopters. The growth of a crack in a fin attachment spar might occur
quickly and if not corrected, lead to failure of a spar, loss of a fin,
a separated fin hitting a rotor, and subsequent loss of control of the
helicopter. Therefore, we have determined that notice and opportunity
for public comment before issuing this AD are impracticable and that
good cause exists for making this amendment effective in fewer than 30
days.

Comments Invited

This AD is a final rule that involves requirements affecting flight
safety, and we did not precede it by notice and opportunity for public
comment. However, we invite you to send us any written data, views, or
arguments concerning this AD. Send your comments to an address listed
under the ADDRESSES section of this AD. Include ``Docket No. FAA-2011-
0923; Directorate Identifier 2009-SW-20-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this AD. We will
consider all comments received by the closing date and may amend this
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 AD.

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 product(s) identified in this
rulemaking action.

Regulatory Findings

We 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.
Therefore, I certify this AD:
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 to the extent that
it justifies making a regulatory distinction; 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.
We prepared an economic evaluation of the estimated costs to comply
with this 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.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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 AD: