Airworthiness Directives; MD Helicopters, Inc., Model 369, YOH-6A, 369A, OH-6A, 369H, 369HM, 369HS, 369HE, 369D, 369E, 369F, and 369FF Helicopters

[Federal Register Volume 72, Number 117 (Tuesday, June 19, 2007)]
[Rules and Regulations]
[Pages 33642-33644]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-11409]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-28449; Directorate Identifier 2007-SW-18-AD; 
Amendment 39-15103; AD 2007-09-51]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters, Inc., Model 369, YOH-
6A, 369A, OH-6A, 369H, 369HM, 369HS, 369HE, 369D, 369E, 369F, and 369FF 
Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 2007-09-51, sent previously to 
all known U.S. owners and operators of the

[[Page 33643]]

specified MD Helicopters, Inc. (MDHI), model helicopters by individual 
letters. This AD requires, before further flight, removing each 
affected tail rotor blade assembly and inspecting the bore of the tail 
rotor blade root fitting. If the blade assembly does not have a smooth 
radius, the AD requires replacing it. The AD also requires identifying 
each airworthy tail rotor blade assembly with the applicable helicopter 
model. This amendment is prompted by a report of an accident after the 
loss of a tail rotor blade. The actions specified by this AD are 
intended to prevent the failure of a tail rotor blade and subsequent 
loss of control of the helicopter.

DATES: Effective July 5, 2007, to all persons except those persons to 
whom it was made immediately effective by Emergency AD 2007-09-51, 
issued on April 27, 2007, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 5, 2007.
    Comments for inclusion in the Rules Docket must be received on or 
before August 20, 2007.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD:
    <bullet> DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically;
    <bullet> Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically;
    <bullet> Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590;
    <bullet> Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays; or
    <bullet> Fax: 202-493-2251.
    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 web at http://www.mdhelicopters.com.
    Examining the Docket: You may examine the docket that contains the 
AD, any comments, and other information on the Internet at http://dms.dot.gov, or in person at the Docket Management System (DMS) Docket 
Offices between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal holidays. The Docket Office (telephone (800) 647-5527) is 
located on the plaza level of the Department of Transportation Nassif 
Building at the street address stated in the ADDRESSES section. 
Comments will be available in the AD docket shortly after the DMS 
receives them.

FOR FURTHER INFORMATION CONTACT: John Cecil, Aviation Safety Engineer, 
FAA, Los Angeles Aircraft Certification Office, Airframe Branch, 3960 
Paramount Blvd., Lakewood, California 90712-4137, telephone (562) 627-
5228, fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: On April 27, 2007, the FAA issued Emergency 
AD 2007-09-51 (EAD) for the specified MDHI model helicopters. The EAD 
requires, before further flight, removing each affected tail rotor 
blade assembly and, using a bright light, inspecting the bore of the 
tail rotor blade root fitting. If the blade assembly does not have a 
smooth radius, the AD requires replacing it. The AD also requires 
identifying each airworthy tail rotor blade assembly with the 
applicable model of helicopter. That action was prompted by a report of 
an accident after the loss of a tail rotor blade. This condition, if 
not corrected, could result in the failure of a tail rotor blade and 
subsequent loss of control of the helicopter.
    MDHI has issued Service Bulletin No. SB369H-247, SB369D-204, 
SB369E-099, and SB369F-084, dated April 26, 2007 (SB), which describes 
procedures for inspecting the tail rotor blade assembly. The SB states 
that reports from the field have shown that there are tail rotor blades 
in operation with a machining defect. The SB further states that these 
blades have a sharp transition in the tapered end of the root fitting 
bore that can cause the tail rotor blade root fitting to fail.
    Since the unsafe condition described is likely to exist or develop 
on other MDHI model helicopters of these same type designs, the FAA 
issued EAD 2007-09-51 to prevent the failure of a tail rotor blade and 
subsequent loss of control of the helicopter. This AD requires the 
following, before further flight:
    <bullet> Remove each affected tail rotor blade assembly. Using a 
bright light, inspect the bore of the tail rotor blade root fitting.
    <bullet> Replace each blade assembly that does not have a smooth 
radius.
    <bullet> Identify the airworthy tail rotor blade assembly with the 
applicable model of helicopter.

The actions must be done by following specified portions of the ASB 
described previously. The short compliance time involved is required 
because the previously described critical unsafe condition can 
adversely affect the controllability and structural integrity of the 
helicopter. Therefore, removing each affected blade assembly, 
inspecting the bore of the tail rotor blade root fitting, and replacing 
each blade assembly that does not have a smooth radius are required 
before further flight, and this AD must be issued immediately.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest. Good cause existed 
to make the AD effective immediately by individual letters issued on 
April 27, 2007, to all known U.S. owners and operators of MD 
Helicopters, Inc., Model 369 (Army YOH-6A), 369A (Army OH-6A), 369H, 
369HM, 369HS, 369HE, 369D, 369E, 369F, and 369FF helicopters. These 
conditions still exist, and the AD is hereby published in the Federal 
Register as an amendment to 14 CFR 39.13 to make it effective to all 
persons.
    The FAA estimates that this AD will affect 980 helicopters of U.S. 
registry and will require about:
    <bullet> 0.1 work hour to identify a blade,
    <bullet> 2 work hours to remove, inspect, install and balance the 
tail rotor blade assemblies on each helicopter,
    <bullet> $80 per work hour labor rate, and
    <bullet> $8,862 for each replacement blade plus hardware.

Based on these figures, we estimate the total cost impact of the AD on 
U.S. operators to be $1,901,592, assuming 1 out of 10 blades are found 
defective for an estimated 196 blades that need replacing.

Comments Invited

    This AD is a final rule that involves requirements that affect 
flight safety and was not preceded by notice and an opportunity for 
public comment; however, we invite you to submit any written data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2007-28449; 
Directorate Identifier 2007-SW-18-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the AD. We will consider 
all comments received by the closing date and may amend the 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

[[Page 33644]]

substantive verbal contact with FAA personnel concerning this AD. Using 
the search function of our docket Web site, you can find and read the 
comments to any of our dockets, including the name of the individual 
who sent the comment. 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.

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 DMS 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 adding a new airworthiness directive to 
read as follows:

2007-09-51 MD Helicopters, Inc.: Amendment 39-15103. Docket No. FAA-
2007-28449; Directorate Identifier 2007-SW-28-AD.

Applicability

    Model 369, YOH-6A, 369A, OH-6A, 369H, 369HM, 369HS, 369HE, 369D, 
369E, 369F, and 369FF helicopters, with a tail rotor blade, part 
number (P/N) 369A1613, 369D21606, 369D21613, 369D21615, or 421-088, 
all dash numbers, installed, certificated in any category.

Compliance

    Before further flight, unless accomplished previously.
    To prevent the loss of a tail rotor blade and subsequent loss of 
control of the helicopter, do the following:
    (a) Inspect each affected tail rotor blade for a smooth radius 
as follows:
    (1) Remove the tail rotor blade assembly by following the 
Accomplishment Instructions, paragraphs 2.B.(1) through 2.B.(3), 
Part 2., of MD Helicopters, Inc., Service Bulletin SB369H-247, 
SB369D-204, SB369E-099, and SB369F-084 dated April 26, 2007 (SB).
    (2) Using a bright light, inspect the bore of the tail rotor 
blade root fitting by following the Accomplishment Instructions, 
paragraphs 2.B.(4) and 2.B.(5), Part 2, and Figures 1 and 2 of the 
SB.
    (b) Replace each blade assembly that does not have a smooth 
radius by following the Accomplishment Instructions, paragraphs 
2.B.(6) and (7), Part 2, and Figure 2 of the SB.
    (c) Identify the airworthy tail rotor blade assembly with the 
applicable model of helicopter by following the Identification, 
paragraphs 3.(1) through 3.(4) of the SB.
    (d) 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: John Cecil, Aviation Safety Engineer, Airframe Branch, 3960 
Paramount Blvd., Lakewood, California 90712-4137, telephone (562) 
627-5228, fax (562) 627-5210, for information about previously 
approved alternative methods of compliance.
    (e) Special flight permits will not be issued.
    (f) Inspecting, replacing, and identifying the tail rotor blade 
assembly shall be done by following the specified portions of MD 
Helicopters, Inc., Service Bulletin SB369H-247, SB369D-204, SB369E-
099, and SB369F-084, dated April 26, 2007. 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 Web 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.
    (g) This amendment becomes effective on July 5, 2007, to all 
persons except those persons to whom it was made immediately 
effective by Emergency AD 2007-09-51, issued April 27, 2007, which 
contained the requirements of this amendment.

    Issued in Fort Worth, Texas, on June 5, 2007.
Mark R. Schilling,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. E7-11409 Filed 6-18-07; 8:45 am]
BILLING CODE 4910-13-P

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