AD 2012-08-18

Airworthiness directive · PT Blade Rupture · Turbomeca Arriel 2B and Arriel 2B1

Effective
May 30, 2012
Published
April 25, 2012 · 77 FR 24585–24587
Issued
April 17, 2012
Models
Arriel 2B, Arriel 2B1
Data sheet
TCDSE00054EN
Registered aircraft
333 matched by model
Product
Engine
Amendment
39-17035
Docket
FAA-2012-0010
Project
2012-NE-03-AD
Issued as
Final rule

Unofficial copy from the Federal Register XML, document 2012-9789. Only the govinfo PDF is the legal edition. DRS record last changed May 30, 2024.

On this page

Summary

We are adopting a new airworthiness directive (AD) for all Turbomeca S.A. Arriel 2B and 2B1 turboshaft engines. This AD was prompted by the discovery of non-conformities of certain power turbine (PT) blade fir-tree roots. This AD requires removing the affected PT blades from service on or before reaching a new reduced life limit for those certain PT blades. We are issuing this AD to prevent PT blade rupture, which could result in an uncommanded in-flight engine shutdown, forced autorotation landing, or accident.

The airworthiness directive

2012-08-18 Turbomeca S.A: Amendment 39-17035; Docket No. FAA-2012-0010; Directorate Identifier 2012-NE-03-AD.

(a) Effective Date

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This AD is effective May 30, 2012.

(b) Affected ADs

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None.

(c) Applicability

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This AD applies to Turbomeca S.A. Arriel 2B and 2B1 turboshaft engines with at least one installed power turbine (PT) blade part number (P/N) 2 292 81 A01 0, serial numbers (S/Ns) 102782 through 120230 inclusive, or, S/Ns 120293 through 120390 inclusive.

(d) Reason

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This AD was prompted by the detection of geometric non-conformities on PT blade fir-tree roots. We are issuing this AD to prevent PT blade rupture, which could result in an uncommanded in-flight engine shutdown, forced autorotation landing, or accident.

(e) Actions and Compliance

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Unless already done, do the following actions within 5,000 flight cycles-since-new (CSN) on the PT blades, or within one month after the effective date of this AD, whichever occurs later.

(1) Replace the PT blades with PT blades eligible for installation; or

(2) Replace the M04 module with an M04 module having PT blades eligible for installation; or

(3) Replace the PT wheel assembly with a PT wheel assembly having PT blades eligible for installation.

(4) Guidance on the replacements specified in paragraphs (e)(1) through (e)(3) can be found in Turbomeca S.A. Alert Mandatory Service Bulletin No. A292 72 2842, Version A, dated September 23, 2011.

(f) Definition

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For the purposes of this AD, a PT blade eligible for installation is one not listed in paragraph (c) of this AD or, one listed in paragraph (c) of this AD with fewer than 5,000 flight CSN.

(g) Installation Prohibition

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From the effective date of this AD:

(1) Do not install a PT blade as listed in paragraph (c) of this AD, that has 5,000 or more flight CSN, into any engine.

(2) Do not install any engine with a PT blade as listed in paragraph (c) of this AD, that has 5,000 or more flight CSN, onto a helicopter.

(h) Alternative Methods of Compliance (AMOCs)

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

(i) Related Information

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(1) For more information about this AD, contact Rose Len, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7772; fax: 781-238-7199; email: rose.len@faa.gov.

(2) Refer to MCAI EASA Airworthiness Directive 2011-0218, dated November 10, 2011, and Turbomeca S.A. Alert Mandatory Service Bulletin No. A292 72 2842, Version A, dated September 23, 2011, for related information.

(3) For service information identified in this AD, contact Turbomeca, 40220 Tarnos, France; phone: 33 05 59 74 40 00; fax: 33 05 59 74 45 15. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125.

(j) Material Incorporated by Reference

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None.

Rule preamble

The FAA’s background, reasoning and cost estimate, published with the AD.

DatesPage 1

This AD is effective May 30, 2012.

AddressesPage 1

For service information identified in this AD, contact Turbomeca, 40220 Tarnos, France; phone: 33 05 59 74 40 00; fax: 33 05 59 74 45 15. You may review copies of the referenced service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125.

For further information contactPage 1

Rose Len, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7772; fax: 781-238-7199; email: rose.len@faa.gov.

DiscussionPage 1

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM published in the Federal Register on January 20, 2012 (77 FR 2930). That NPRM proposed to require removing the affected PT blades from service on or before reaching a new reduced life limit for those certain PT blades.

CommentsPage 1

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM (77 FR 2930, January 20, 2012).

Clarification of Compliance TimePage 1

Since we issued the proposed AD, we determined that we need to clarify the compliance time. The proposed AD stated 5,000 flight cycles. We changed the AD to state 5,000 flight cycles-since-new.

ConclusionPage 1

We reviewed the relevant data and determined that air safety and the public interest require adopting the AD with the change described previously.

Costs of CompliancePage 1

Based on the service information, we estimate that this AD will affect about 150 engines installed on helicopters of U.S. registry. We also estimate that it will take about 4 work-hours per product to comply with this AD. The average labor rate is $85 per work-hour. A prorated replacement M04 module will cost about $20,000 per engine. Based on these figures, we estimate the cost of the AD on U.S. operators to be $3,051,000.

Authority for This RulemakingPage 1

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 findingsPage 1

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.

For the reasons discussed above, I certify that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Is not a “significant rule” under 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.

Adoption of the AmendmentPage 1

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

1. The authority citation for part 39 continues to read as follows:

Adoption of the amendmentPage 1

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

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 333

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Eurocopter250 aircraft
  • American Eurocopter52 aircraft
  • Eurocopter France12 aircraft
  • Airbus Helicopters7 aircraft
  • Airbus Helicopters Deutschland7 aircraft
  • Other makers25 aircraft
By year built
19912018
Registered aircraft by year built: 324 aircraft
19911
19983
19994
20005
200117
200225
200324
200418
200518
200618
200729
200840
200934
201031
201135
201215
20153
20161
20171
20182

9 with no year recorded

By model

Aircraft

See all 333 aircraft