
[Federal Register: March 12, 2008 (Volume 73, Number 49)]
[Rules and Regulations]               
[Page 13096-13098]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr12mr08-10]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-29342; Directorate Identifier 2007-SW-08-AD; 
Amendment 39-15411; AD 2008-05-17]
RIN 2120-AA64

 
Airworthiness Directives; MD Helicopters, Inc. Model 600N 
Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This document supersedes an existing airworthiness directive 
(AD) for MD Helicopters, Inc. (MDHI) Model 600N helicopters. That AD 
currently requires interim initial and repetitive inspections of 
tailboom parts, installing

[[Page 13097]]

six inspection holes in the aft fuselage skin panels, installing 
tailboom attachment bolt washers, modifying both access covers, and 
replacing broken attachment bolts. The current AD also provides for 
modifying the fuselage aft section as an optional terminating action. 
This amendment requires modifying the fuselage aft section within the 
next 24 months to strengthen the tailboom attachment fittings and upper 
longerons. The actions specified by this AD are intended to prevent 
failure of the tailboom attachment fittings, separation of the tailboom 
from the helicopter, and subsequent loss of control of the helicopter.

DATES: Effective April 16, 2008.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 16, 2008.

ADDRESSES: You may get the service information identified in this AD 
from MD Helicopters Inc., Attn: Customer Support Division, 4555 E. 
McDowell Rd., Mail Stop M615, Mesa, Arizona 85215-9734, telephone 1-
800-388-3378, fax 480-346-6813, or on the Internet at http://
www.mdhelicopters.com.

EXAMINING THE DOCKET: You may examine the docket that contains this AD, 
any comments, and other information on the Internet at http://
www.regulations.gov or at the Docket Operations office, West Building 
Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, 
DC.

FOR FURTHER INFORMATION CONTACT: Jon Mowery, Aviation Safety Engineer, 
FAA, Los Angeles Aircraft Certification Office, Airframe Branch, 3960 
Paramount Blvd., Lakewood, California 90712, telephone (562) 627-5322, 
fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 by 
superseding AD 2006-08-12, Amendment 39-14569 (71 FR 24808, April 27, 
2006), which superseded AD 2001-24-51, Amendment 39-12706 (67 FR 17934, 
April 12, 2002), for the specified MDHI model helicopters was published 
in the Federal Register on October 19, 2007 (72 FR 59227). The action 
proposed to require modifying the fuselage aft section within the next 
24 months to strengthen the tailboom attachment fittings and upper 
longerons.
    On January 12, 2004, MDHI issued Technical Bulletin (TB) TB600N-007 
specifying procedures, tooling, replacement parts, and supplies needed 
for modifying the fuselage aft section and tailboom. TB600N-007R1, 
dated April 13, 2006, superseded TB600N-007 to correct some tooling, 
replacement parts, and supplies. TB600N-007R2, dated October 5, 2006, 
superseded TB600N-007R1 to correct tooling part numbers and re-sequence 
some assembly steps. These TBs specify that any aircraft complying with 
any of these revisions meets the intent of the other TBs.
    In AD 2006-08-12, we incorporated by reference TB600N-007R1, dated 
April 13, 2006. Since issuing that AD, MDHI has issued TB600N-007R2, 
dated October 5, 2006 (TB), which updates previous issues by further 
specifying procedures for modifying the fuselage aft section to 
strengthen the tailboom attachment fittings and upper longerons. This 
latest revision continues to caution that a high level of sheet metal 
expertise and experience is required to perform this modification.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposal or the FAA's determination of the cost to the public. The FAA 
has determined that air safety and the public interest require adopting 
the rule as proposed.
    The FAA estimates that this AD will affect 18 helicopters of U.S. 
registry, and the required actions will take about 322 work hours to 
modify each helicopter at an average labor rate of $80 per work hour. 
Required parts will cost about $14,960 per helicopter. The manufacturer 
states in its TB that those complying with the TB within 3 years of the 
issue date are eligible for special pricing and technical assistance. 
Based on these figures, we estimate the total cost impact of the AD on 
U.S. operators to be $732,960, assuming no special pricing from the 
manufacturer.

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 the 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. 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. See the AD docket to examine the economic evaluation.

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.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

0
Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by removing Amendment 39-14569 (71 FR 
24808, April 27, 2006) and by adding a new airworthiness directive 
(AD), Amendment 39-15411, to read as follows:

2008-05-17 MD Helicopters, Inc.: Amendment 39-15411, Docket No. FAA-
2007-29342, Directorate Identifier 2007-SW-08-AD. Supersedes AD 
2006-08-12, Amendment 39-14569, Docket No. FAA-2006-24518, 
Directorate Identifier 2006-SW-10-AD.

    Applicability: Model 600N helicopters, serial numbers with a 
prefix ``RN'' and 003 through 058, that have not been modified in

[[Page 13098]]

the fuselage aft section to strengthen the tailboom attachments and 
longerons per MD Helicopters (MDHI) Technical Bulletin (TB) TB600N-
007, dated January 12, 2004; TB600N-007R1, dated April 13, 2006, or 
TB600N-007R2, dated October 5, 2006, certificated in any category.
    Compliance: Required within the next 24 months, unless 
accomplished previously.
    To prevent failure of the tailboom attachment fittings, 
separation of the tailboom from the helicopter, and subsequent loss 
of control of the helicopter, do the following:
    (a) Modify the fuselage aft section to strengthen the tailboom 
attach fittings and upper longerons by following paragraph 2, 
Accomplishment Instructions, of MDHI TB600N-007R2, dated October 5, 
2006, except you are not required to contact the manufacturer. This 
modification to the fuselage aft section is terminating action for 
the requirements of this AD.
    (b) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Contact the Manager, Los Angeles Aircraft Certification Office, FAA, 
Attn: Jon Mowery, Aviation Safety Engineer, Airframe Branch, 3960 
Paramount Blvd., Lakewood, California 90712, telephone (562) 627-
5322, fax (562) 627-5210, for information about previously approved 
alternative methods of compliance.
    (c) Modifying the fuselage aft section shall be done by 
following the specified portions of MD Helicopters Technical 
Bulletin (TB) TB600N-007R2, dated October 5, 2006. The Director of 
the Federal Register approved this incorporation by reference in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from MD Helicopters Inc., Attn: Customer Support Division, 
4555 E. McDowell Rd., Mail Stop M615, Mesa, Arizona 85215-9734, 
telephone 1-800-388-3378, fax 480-346-6813, or on the Internet at 
http://www.mdhelicopters.com. Copies may be inspected at the FAA, 
Office of the Regional Counsel, Southwest Region, 2601 Meacham 
Blvd., Room 663, Fort Worth, Texas 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/code_of_federal_regulations/
ibr_locations.html.
    (d) This amendment becomes effective on April 16, 2008.

    Issued in Fort Worth, Texas, on February 27, 2008.
Mark R. Schilling,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
 [FR Doc. E8-4489 Filed 3-11-08; 8:45 am]

BILLING CODE 4910-13-P
