[Federal Register Volume 70, Number 213 (Friday, November 4, 2005)]
[Proposed Rules]
[Pages 67099-67101]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-22007]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22364; Directorate Identifier 2005-NE-26-AD]
RIN 2120-AA64


Airworthiness Directives; Turbomeca Arriel 1B, 1D and 1D1 
Turboshaft Engines

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Turbomeca Arriel 1B, 1D and 1D1 turboshaft engines. This proposed 
AD would require inspecting the 2nd stage nozzle guide vanes (NGV2) for 
wall thickness. This proposed AD results from one instance of a 
fractured 2nd stage turbine blade followed by an uncommanded engine 
shutdown. We are proposing this AD to detect and prevent perforation of 
the NGV2 that could cause fracture of a turbine blade that could result 
in an uncommanded engine in-flight shutdown.

DATES: We must receive any comments on this proposed AD by January 3, 
2006.

[[Page 67100]]


ADDRESSES: Use one of the following addresses to comment on this 
proposed 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 Turbomeca S.A., 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.

FOR FURTHER INFORMATION CONTACT: Christopher Spinney, Aerospace 
Engineer, Engine Certification Office, FAA, Engine and Propeller 
Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; 
telephone (781) 238-7175; fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send us any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2005-22364; 
Directorate Identifier 2005-NE-26-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    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 proposed AD. Using the search function of the 
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 proposal, 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 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 docket office 
receives them.

Discussion

    The Direction Generale de L'Aviation Civile (DGAC), which is the 
airworthiness authority for France, notified us that an unsafe 
condition might exist on certain Turbomeca S.A. Arriel 1B, 1D and 1D1 
turboshaft engines. The affected engines are those modified to TU 202, 
except those having NGV2 vanes with serial numbers or specific marks 
identified in Turbomeca Mandatory Service Bulletin (MSB) No. 292 72 
0231, Update No. 5, dated July 22, 2004. The DGAC advises that in order 
to detect and prevent a possible perforation of the NGV2, they are 
requiring inspection of the NGV2 for wall thickness. Perforation of the 
NGV2 could cause an aerodynamic wake upstream of the 2nd stage turbine. 
Such a wake could lead to the fracture of a 2nd stage turbine blade 
followed by an uncommanded engine in-flight shutdown. On a single-
engine helicopter, this in-flight shutdown could lead to an emergency 
landing by autorotation or an accident.

Relevant Service Information

    We have reviewed and approved the technical contents of Turbomeca 
MSB No. 292 72 0231, Update No. 5, dated July 22, 2004, that describes 
procedures for removing each vane of the NGV2, checking the vane 
thickness, and replacing the NGV2 if the vane thickness is below the 
defined criteria. The DGAC classified this MSB as mandatory and issued 
airworthiness directive No. F-2004-088 R1, dated August 4, 2004, in 
order to ensure the airworthiness of these NGV2 vanes in France.

FAA's Determination and Requirements of the Proposed AD

    These engines, manufactured in France, are type-certificated for 
operation in the United States under the provisions of section 21.29 of 
the Federal Aviation Regulations (14 CFR 21.29) and the applicable 
bilateral airworthiness agreement. In keeping with this bilateral 
airworthiness agreement, the DGAC kept us informed of the situation 
described above. We have examined the DGAC's findings, reviewed all 
available information, and determined that AD action is necessary for 
products of this type design that are certificated for operation in the 
United States. For this reason, we are proposing this AD, which would 
require inspection of the NGV2 wall thickness. The proposed AD would 
require you to use the service information described previously to 
perform these actions.

Costs of Compliance

    There are about 2,000 Turbomeca Arriel 1B, 1D and 1D1 turboshaft 
engines of the affected design in the worldwide fleet. We estimate that 
this proposed AD would affect 571 engines installed on helicopters of 
U.S. registry. We also estimate that it would take about 0.5 work hours 
per engine to perform the proposed actions, and that the average labor 
rate is $65 per work hour. No parts are required. Based on these 
figures, we estimate the total cost of the proposed AD to U.S. 
operators to be $18,558.

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 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

[[Page 67101]]

responsibilities among the various levels of government.
    For the reasons discussed above, I certify that the 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. Would 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. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Under the authority delegated to me by the Administrator, the 
Federal Aviation Administration 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:

Turbomeca: Docket No. FAA-2005-22364; Directorate Identifier 2005-
NE-26-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by January 3, 
2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Turbomeca Arriel 1B, 1D and 1D1 certain 
turboshaft engines, modified to TU 202. These engines are installed 
on, but not limited to, Eurocopter France AS350A, AS350B, AS350B1, 
and AS350B2 helicopters.

Unsafe Condition

    (d) This AD results from one instance of a fractured 2nd stage 
turbine blade followed by an uncommanded engine shutdown. We are 
issuing this AD to detect and prevent perforation of the NGV2 that 
could cause fracture of a turbine blade that could result in an 
uncommanded engine in-flight shutdown.

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.

Inspect 2nd Stage Nozzle Guide Vanes (NGV2)

    (f) At the next shop visit or the next accessibility of the NGV2 
after the effective date of this AD, whichever occurs first, check 
the thickness of the material on each NGV2 using the Instructions to 
be Incorporated of Turbomeca Mandatory Service Bulletin (MSB) No. 
292 72 0231, Update No. 5, dated July 22, 2004. Replace the NGV2 if 
the vane thickness is below the defined criteria.
    (g) Inspections carried out before the effective date of this 
AD, using an earlier update of MSB No. 292 72 0231, are acceptable 
alternatives to the requirements of this AD.
    (h) Information regarding NGV2's that have already had the 
actions required by this AD done and are exempt from the inspections 
using paragraph (e) of this AD can be found in MSB No. 292 72 0231, 
Update No. 5, dated July 22, 2004.

Definitions

    (i) For the purposes of this AD the following definitions apply:
    (1) A shop visit is defined as introduction of the engine into a 
shop for the purposes of deep maintenance and the separation of a 
major mating flange.
    (2) Accessibility of the NGV2 is defined as removal of the NGV2 
from the engine regardless of the location or reason for removal.

Alternative Methods of Compliance (AMOCs)

    (j) The Manager, Engine 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) DGAC airworthiness directive No. F-20040-088 R1 also 
addresses the subject of this AD.

    Issued in Burlington, Massachusetts, on October 31, 2005.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-22007 Filed 11-3-05; 8:45 am]
BILLING CODE 4910-13-P