Airworthiness Directives; Turbomeca Turmo IV A and IV C Series Turboshaft Engines

[Federal Register Volume 71, Number 221 (Thursday, November 16, 2006)]
[Rules and Regulations]
[Pages 66664-66665]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-19274]



[[Page 66664]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25970; Directorate Identifier 99-NE-12-AD; 
Amendment 39-14829; AD 2006-23-17]
RIN 2120-AA64


Airworthiness Directives; Turbomeca Turmo IV A and IV C Series 
Turboshaft Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is superseding an existing airworthiness directive 
(AD) for Turbomeca Turmo IV A and IV C series turboshaft engines. That 
AD currently requires borescope and eddy current inspections or 
ultrasonic inspections of centrifugal compressor intake wheel blades 
for cracks and evidence of corrosion pitting, and replacement with 
serviceable parts. This AD requires the same actions, but would require 
borescope inspections at more frequent intervals for certain engines. 
This AD results from Turbomeca's review of the engines' service 
experience that determined more frequent borescope inspections are 
required on engines not modified to the TU 191, TU 197, or TU 224 
standard. We are issuing this AD to prevent centrifugal compressor 
intake wheel blade cracks, which can result in engine in-flight power 
loss, engine shutdown, or forced landing.

DATES: This AD becomes effective December 21, 2006. The Director of the 
Federal Register approved the incorporation by reference of certain 
publications listed in the regulations as of December 21, 2006.

ADDRESSES: You can get the service information identified in this AD 
from Turbomeca, 40220 Tarnos, France; telephone 33 05 59 74 40 00, fax 
33 05 59 74 45 15.
    You may examine the AD docket on the Internet at http://dms.dot.gov 
or in Room PL-401 on the plaza level of the Nassif Building, 400 
Seventh Street, SW., Washington, DC.

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

SUPPLEMENTARY INFORMATION: The FAA proposed to amend 14 CFR Part 39 
with a proposed AD. The proposed AD applies to Turbomeca Turmo IV A and 
IV C series turboshaft engines. We published the proposed AD in the 
Federal Register on February 9, 2006 (71 FR 6691). That action proposed 
to require initial and repetitive borescope and eddy current 
inspections or ultrasonic inspections of centrifugal compressor intake 
wheel blades for cracks and evidence of corrosion pitting, and, if 
found cracked or if there is evidence of corrosion pitting, replacement 
with serviceable parts. Additionally, it proposed to require borescope 
inspections at more frequent intervals for certain engines.

Examining the AD Docket

    You may examine the docket that contains the AD, any comments 
received, and any final disposition in person at the Docket Management 
Facility Docket Office between 9 a.m. and 5 p.m., Monday through 
Friday, except Federal holidays. The Docket Office (telephone (800) 
647-5227) is located 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 DMS receives them.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We received no comments on the proposal or on 
the determination of the cost to the public.

Docket Number Change

    We are transferring the docket for this AD to the Docket Management 
System as part of our on-going docket management consolidation efforts. 
The new Docket No. is FAA-2006-25970. The old Docket No. became the 
Directorate Identifier, which is 99-NE-12-AD. This final rule might get 
logged into the DMS docket, ahead of the proposed AD and comments 
received, as we are in the process of sending those items to the DMS.

Conclusion

    We have carefully reviewed the available data and determined that 
air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

    We estimate that this AD will affect 36 Turbomeca Turmo IV A and IV 
C series turboshaft engines installed on helicopters of U.S. registry. 
We also estimate that it will take about 41 work-hours per engine to 
perform the inspections, including disassembling and assembling 
engines, and that the average labor rate is $65 per work-hour. A 
replacement centrifugal compressor assembly costs about $21,651. Based 
on these figures, the cost per inspection and replacement is estimated 
to be $24,316. Based on these figures, we estimate the total cost of 
the AD to U.S. operators to be $875,390.

Special Flight Permits Paragraph Removed

    Paragraph (e) of the current AD, AD 2003-11-09, contains a 
paragraph pertaining to special flight permits. Even though this AD 
does not contain a similar paragraph, we have made no changes with 
regard to the use of special flight permits to operate the helicopter 
to a repair facility to do the work required by this AD. In July 2002, 
we published a new Part 39 that contains a general authority regarding 
special flight permits and airworthiness directives; see Docket No. 
FAA-2004-8460, Amendment 39-9474 (69 FR 47998, July 22, 2002). Thus, 
when we now supersede ADs we will not include a specific paragraph on 
special flight permits unless we want to limit the use of that general 
authority granted in section 39.23.

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 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:

[[Page 66665]]

    (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); 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 summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary at the 
address listed under ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the Federal Aviation Administration amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by removing Amendment 39-13168 (68 FR 
31970, May 29, 2003) and by adding a new airworthiness directive, 
Amendment 39-14829, to read as follows:

2006-23-17 Turbomeca: Amendment 39-14829. Docket No. FAA-2006-25970; 
Directorate Identifier 99-NE-12-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective December 
21, 2006.

Affected ADs

    (b) This AD supersedes AD 2003-11-09, Amendment 39-13168.

Applicability

    (c) This AD applies to Turbomeca Turmo IV A and IV C series 
turboshaft engines. These engines are installed on but not limited 
to Aerospatiale SA 330--PUMA helicopters.

Unsafe Condition

    (d) This AD results from Turbomeca's review of the engines' 
service experience that determined more frequent borescope 
inspections are required on engines not modified to the TU 191, TU 
197, or TU 224 standard. The actions specified in this AD are 
intended to prevent centrifugal compressor intake wheel blade 
cracks, which can result in engine in-flight power loss, engine 
shutdown, or forced landing.

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.

Engine Modification Before Further Flight

    (f) For engines modified to the TU 197 standard, but not to the 
TU 191 or TU 224 standard, before further flight, remove the TU 197 
standard and install the TU 224 standard.

Initial Inspections

    (g) For all engines, borescope-inspect, and either eddy current-
inspect (ECI) or ultrasonic-inspect (UI) the centrifugal compressor 
intake wheel blades using paragraphs 2.B.(1)(a) through 2.B.(1)(g) 
of Turbomeca Mandatory Service Bulletin A249 72 0100, Update No. 5, 
dated February 25, 2005, and the criteria in the following Table 1:

                                          Table 1.--Inspection Criteria
----------------------------------------------------------------------------------------------------------------
                                        Then borescope-inspect       Were traces of       Then confirm corrosion
   If engine modification level is:     centrifugal compressor     corrosion found at    by performing ECI or UI
                                         intake wheel blades:    borescope-inspection?           within:
----------------------------------------------------------------------------------------------------------------
(1) Pre TU 191 and Pre TU 224........  Within 200 flight hours- (i) Yes................  Six months-or 50 flight
                                        since-last inspection.                            hours-since-borescope
                                                                                          inspection, whichever
                                                                                          occurs first.
                                                                (ii) No................  Two hundred flight
                                                                                          hours-since-borescope
                                                                                          inspection.
(2) Post TU 191 or Post TU 224.......  Within 1,000 flight      (i) Yes................  Six months-or 50 flight
                                        hours-since-last                                  hours-since-borescope
                                        inspection.                                       inspection, whichever
                                                                                          occurs first.
                                                                (ii) No................  One thousand flight
                                                                                          hours-since-borescope
                                                                                          inspection.
----------------------------------------------------------------------------------------------------------------

    (h) Thereafter, perform repetitive inspections using the 
criteria in Table 1 of this AD.
    (i) Remove centrifugal compressor intake wheel blades confirmed 
cracked or pitted.

Alternative Methods of Compliance

    (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.

Material Incorporated by Reference

    (k) You must use Turbomeca Mandatory Service Bulletin A249 72 
0100, Update No. 5, dated February 25, 2005, to perform the actions 
required by this AD. The Director of the Federal Register approved 
the incorporation by reference of this service bulletin in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You can get a 
copy of this service information from Turbomeca, 40220 Tarnos, 
France; telephone 33 05 59 74 40 00, fax 33 05 59 74 45 15. You may 
review copies at the FAA, New England Region, Office of the Regional 
Counsel, 12 New England Executive Park, Burlington, MA; or at the 
National Archives and Records Administration (NARA). For information 
on the availability of this material at NARA, call 202-741-6030, or 
go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

Related Information

    (l) Direction Generale de L'Aviation Civile airworthiness 
directive F-2005-037, dated March 2, 2005, also addresses the 
subject of this AD.

    Issued in Burlington, Massachusetts, on November 7, 2006.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. E6-19274 Filed 11-15-06; 8:45 am]
BILLING CODE 4910-13-P

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