Document ID: FAA-2005-21242-0026
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Turbomeca Arriel 1B, 1D, 1D1, and 1S1 Turboshaft Engines
Posted Date: 2010-03-10T05:00Z

[Federal Register: March 10, 2010 (Volume 75, Number 46)]
[Proposed Rules]               
[Page 11072-11075]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr10mr10-12]                         

=======================================================================
-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-21242; Directorate Identifier 2005-NE-09-AD]
RIN 2120-AA64

 
Airworthiness Directives; Turbomeca Arriel 1B, 1D, 1D1, and 1S1 
Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for certain Turbomeca Arriel 1B, 1D, 1D1, and 1S1 
turboshaft engines. That AD requires initial and repetitive relative 
position checks of the gas generator 2nd stage turbine blades on 
Turbomeca Arriel 1B (that incorporate Turbomeca Modification (mod) TU 
148), Arriel 1D, 1D1, and 1S1 turboshaft engines that do not 
incorporate mod TU 347. That AD also requires initial and repetitive 
replacements of 2nd stage turbines on Arriel 1B, 1D, and 1D1 engines. 
This proposed AD would require lowering the repetitive threshold for 
relative position checks on Arriel 1B engines. This proposed AD would 
also require lowering the initial and repetitive thresholds for 
replacement of 2nd stage turbines on Arriel 1B, 1D, and 1D1 engines. 
This proposed AD results from reports of new cases of failures of 2nd 
stage turbine blades since we issued AD 2008-07-01. We are proposing 
this AD to prevent the failure of 2nd stage turbine blades, which could 
result in an uncommanded in-flight engine

[[Page 11073]]

shutdown, and a subsequent forced autorotation landing or accident.

DATES: We must receive any comments on this proposed AD by April 9, 
2010.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD.
     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.

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-2005-
21242; Directorate Identifier 2005-NE-09-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).

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

Discussion

    On March 17, 2008, the FAA issued AD 2008-07-01, Amendment 39-15442 
(73 FR 15866, March 26, 2008). That AD requires initial and repetitive 
relative position checks of the gas generator 2nd stage turbine blades 
on Turbomeca Arriel 1B (that incorporate mod TU 148), 1D, 1D1, and 1S1 
turboshaft engines that do not incorporate mod TU 347. That AD also 
requires initial and repetitive replacements of 2nd stage turbines on 
1B, 1D, and 1D1 engines. The European Aviation Safety Agency (EASA), 
which is the Technical Agent for the Member States of the European 
Community, recently notified us that an unsafe condition likely exists 
on Turbomeca Arriel 1B, 1D, 1D1, and 1S1 turboshaft engines.

Since AD 2008-07-01 Was Issued

    Since AD 2008-07-01 was issued, EASA reports that in engines that 
do not incorporate mod TU 347, new cases of gas generator 2nd stage 
turbine blade release have occurred, at lower blade service lives than 
previously reported. EASA issued AD 2009-0236, dated October 29, 2009, 
to optimize the 2nd stage turbine blade life limit and the replacement 
allowances for turbines currently in service in Europe, based on parts 
availability while keeping the risk level within acceptable limits.

Relevant Service Information

    We have reviewed and approved the technical contents of Turbomeca 
Mandatory Service Bulletin (MSB) No. A292 72 0807, Version E, dated 
October 29, 2009, that describes procedures for the relative position 
check of 2nd stage turbine blades, and replacement of 2nd stage 
turbines that do not incorporate mod TU 347, with inspected 2nd stage 
turbines, or with 2nd stage turbines that incorporate mod TU 347, on 
Arriel 1B, 1D, and 1D1 engines. We have also reviewed and approved the 
technical contents of Turbomeca MSB No. A292 72 0810, Version C, dated 
July 24, 2009, that describes procedures for the relative position 
check of 2nd stage turbine blades on Arriel 1S1 engines. EASA 
classified these MSBs as mandatory and issued AD 2009-0236, dated 
October 29, 2009, to ensure the airworthiness of these Turbomeca Arriel 
engines in Europe.

Bilateral Agreement Information

    This engine model is manufactured in France, and is 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. Under this bilateral 
airworthiness agreement, EASA kept us informed of the situation 
described above. We have examined the findings of the EASA, 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.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other products 
of this same type design. We are proposing this AD supersedure, which 
would require lowering the repetitive threshold for relative position 
checks on Arriel 1B engines. This proposed AD would also require 
lowering the initial and repetitive thresholds for replacement of 2nd 
stage turbines on Arriel 1B, 1D, and 1D1 engines. The proposed AD would 
require that you do these actions using the service information 
described previously.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 587 Turbomeca Arriel 1B, 1D, 1D1, and 1S1 turboshaft 
engines installed on products of U.S. registry. We also estimate that 
it would take about 2 work-hours per engine to perform one inspection, 
and about 40 work-hours per engine to replace the gas turbine discs and 
blades. The average labor rate is $85 per work-hour. Required parts 
would cost about $54,000 per engine. Based on these figures, we 
estimate the cost of the proposed AD on U.S. operators to be 
$33,793,590.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I,

[[Page 11074]]

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 responsibilities among the various levels of government.
    For the reasons discussed above, I certify that the proposed 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); 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, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, 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 removing Amendment 39-15442 (73 FR 
15866, March 26, 2008) and by adding a new airworthiness directive, to 
read as follows:

Turbomeca: Docket No. FAA-2005-21242; Directorate Identifier 2005-
NE-09-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by April 9, 
2010.

Affected ADs

    (b) This AD supersedes AD 2008-07-01, Amendment 39-15442.

Applicability

    (c) This AD applies to Turbomeca Arriel 1B (that incorporate 
Turbomeca Modification (mod) TU 148), Arriel 1D, 1D1, and 1S1 
engines that do not incorporate mod TU 347. Arriel 1B engines are 
installed on, but not limited to, Eurocopter AS-350B and AS-350BA 
``Ecureuil'' helicopters. Arriel 1D engines are installed on, but 
not limited to, Eurocopter France AS-350B1 ``Ecureuil'' helicopters. 
Arriel 1D1 engines are installed on, but not limited to, Eurocopter 
France AS-350B2 ``Ecureuil'' helicopters. Arriel 1S1 engines are 
installed on, but not limited to, Sikorsky Aircraft Corporation S-
76C helicopters.

Unsafe Condition

    (d) This AD results from reports of new cases of failures of 2nd 
stage turbine blades since we issued AD 2008-07-01. We are issuing 
this AD to prevent the failure of 2nd stage turbine blades, which 
could result in an uncommanded in-flight engine shutdown, and a 
subsequent forced autorotation landing or accident.

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.

Initial Relative Position Check of 2nd Stage Turbine Blades

    (f) Do an initial relative position check of the 2nd stage 
turbine blades using the Turbomeca Mandatory Service Bulletins 
(MSBs) specified in the following Table 1. Do the check before 
reaching any of the intervals specified in Table 1 or within 50 
hours time-in-service after the effective date of this AD, whichever 
occurs later.

          Table 1--Initial and Repetitive Relative Position Check Intervals of 2nd Stage Turbine Blade
----------------------------------------------------------------------------------------------------------------
                                           Initial relative                                 Mandatory service
        Turbomeca engine model         position check interval    Repetitive interval            bulletin
----------------------------------------------------------------------------------------------------------------
Arriel 1B (that incorporate mod TU     Within 1,200 hours time- Within 150 hours time-   A292 72 0807, Version
 148), 1D1, and 1D.                     since-new (TSN) or       in-service-since-last-   E, dated October 29,
                                        time-since-overhaul      relative-position-       2009, paragraphs
                                        (TSO) or 3,500 cycles-   check (TSLRPC).          2B(1)(a) and (b), or
                                        since-new (CSN) or                                2B(2)(a).
                                        cycles-since-overhaul
                                        (CSO), whichever
                                        occurs earlier.
Arriel 1S1...........................  Within 1,200 hours TSN   Within 150 hours TSLRPC  A292 72 0810, Version
                                        or TSO or 3,500 CSN or                            C, dated July 24,
                                        CSO, whichever occurs                             2009, paragraphs
                                        earlier.                                          2B(1)(a) and (b), or
                                                                                          2B(2)(a), (b), and
                                                                                          (c).
----------------------------------------------------------------------------------------------------------------

Repetitive Relative Position Check of 2nd Stage Turbine Blades

    (g) Recheck the relative position of 2nd stage turbine blades at 
the TSLRPC intervals specified in Table 1 of this AD, using the 
Turbomeca MSBs indicated.

Credit for Previous Relative Position Checks

    (h) Credit is allowed for previous relative position checks of 
2nd stage turbine blades done using the following Turbomeca MSBs:
    (1) MSB No. A292 72 0263, Update Nos. 1 through 5.
    (2) MSB No. A292 72 0807, Original, and Update No. 1 through 
Version D.
    (3) MSB No. A292 72 0809, Update No. 1.
    (4) MSB No. A292 72 0810, Original, and Version A through 
Version B.

Initial Replacement of 2nd Stage Turbines on Arriel 1B Engines

    (i) Initially replace the Arriel 1B 2nd stage turbine disk and 
blades with an inspected 2nd stage turbine that does not incorporate 
mod TU 347 and is fitted with new blades or with a 2nd stage turbine 
that incorporates

[[Page 11075]]

mod TU 347, using Turbomeca MSB No. A292 72 0807, Version E, dated 
October 29, 2009, paragraphs 2B(1)(c) or (d), or 2B(2)(b) or (c), at 
the following times:
    (1) Replace before further flight on engines with a 2nd stage 
turbine disk having accumulated more than 2,200 hours TIS since-new 
or since-last-inspection, whichever occurs later, or with 2nd stage 
turbine blades that have accumulated more than 3,000 hours TIS 
since-new.
    (2) For engines with 2nd stage turbine blades having accumulated 
on the effective date of this AD, more than 1,800 hours TIS since-
new, but 3,000 or fewer hours TIS since-new, replace before reaching 
any of the following:
    (i) 400 hours TIS from the effective date of this AD, or
    (ii) 3,000 hours TIS since-new on the 2nd stage turbine blades, 
or
    (iii) 2,200 hours TIS since-new or since-last-inspection, 
whichever occurs later, on the 2nd stage turbine disk.
    (3) For engines with 2nd stage turbine blades having accumulated 
on the effective date of this AD, more than 900 hours TIS since-new, 
but 1,800 or fewer hours TIS since-new, replace before reaching any 
of the following:
    (i) 800 hours TIS from the effective date of this AD, or
    (ii) 2,200 hours TIS since-new or since-last-inspection, 
whichever occurs later, on the 2nd stage turbine disk.
    (4) For engines with 2nd stage turbine blades having accumulated 
on the effective date of this AD, 900 or fewer hours TIS since-new, 
replace before the 2nd stage turbine blades have accumulated 1,200 
hours TIS since-new.

Repetitive Replacements of 2nd Stage Turbines on Arriel 1B Engines

    (j) Thereafter, for 2nd stage turbines that do not incorporate 
mod TU 347, replace the 2nd stage turbine disk and blades before the 
blades have accumulated 1,200 hours TIS since-new.

Initial Replacement of 2nd Stage Turbines on Arriel 1D and 1D1 Engines

    (k) Initially replace the Arriel 1D and 1D1 2nd stage turbine 
disk and blades with an inspected turbine that does not incorporate 
mod TU 347 and is fitted with new blades or with a turbine that 
incorporates mod TU 347, using Turbomeca MSB No. A292 72 0807, 
Version E, dated October 29, 2009, paragraphs 2B(1)(c) or (d), or 
2B(2)(b) or (c), at the following times:
    (1) Replace before further flight on engines with a 2nd stage 
turbine disk having accumulated more than 1,500 hours TIS since-new 
or since-last-inspection, whichever occurs later, or with 2nd stage 
turbine blades having accumulated more than 1,500 hours TIS since-
new.
    (2) For engines with 2nd stage turbine blades having accumulated 
on the effective date of this AD, more than 900 hours TIS since-new, 
but 1,500 or fewer hours TIS since-new, replace before the 2nd stage 
turbine blades have accumulated 1,500 hours TIS since-new, or before 
the 2nd stage turbine disk has accumulated 1,500 hours TIS since-
new, whichever occurs first.
    (3) For engines with 2nd stage turbine blades having accumulated 
on the effective date of this AD, 900 or fewer hours TIS since-new, 
replace before the 2nd stage turbine blades have accumulated 1,200 
hours TIS since-new.

Repetitive Replacements of 2nd Stage Turbines on Arriel 1D and 1D1 
Engines

    (l) Thereafter, for 2nd stage turbines that do not incorporate 
mod TU 347, replace the 2nd stage turbine disk and blades before the 
blades have accumulated 1,200 hours TIS since-new.

Relative Position Check Continuing Compliance Requirements

    (m) All 2nd stage turbines, including those that are new or 
overhauled, must continue to comply with the actions specified in 
paragraphs (f) and (g) of this AD, unless mod TU 347 has been 
incorporated.

Optional Terminating Action

    (n) Installing a new turbine, P/N 0 292 25 039 0, (incorporation 
of mod TU 347) terminates the requirements to perform the repetitive 
actions specified in paragraphs (g), (j), and (l) of this AD.

Alternative Methods of Compliance

    (o) 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

    (p) The EASA airworthiness directive 2009-0236, dated October 
29, 2009, also addresses the subject of this AD.
    (q) 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, 
for more information about this AD.

    Issued in Burlington, Massachusetts, on March 1, 2010.
Thomas A. Boudreau,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 2010-5028 Filed 3-9-10; 8:45 am]
BILLING CODE 4910-13-P