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

[Federal Register Volume 69, Number 209 (Friday, October 29, 2004)]
[Rules and Regulations]
[Pages 63054-63055]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-24228]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-SW-51-AD; Amendment 39-13840; AD 2004-22-12]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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

SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
MD Helicopters, Inc. Model 600N helicopters that requires replacing the 
fuselage Station 75 control support bracket assembly (control support 
bracket), reducing the life limit, and revising the Limitations section 
of the applicable maintenance manual to state the reduced life limits 
on certain serial-numbered helicopters. This amendment is prompted by 
information received from the manufacturer indicating that the fatigue 
life of the control support bracket is shorter than the original 
analysis indicated. The actions specified by this AD are intended to 
prevent failure of the control support bracket and subsequent loss of 
control of the helicopter.

DATES: Effective December 3, 2004.

FOR FURTHER INFORMATION CONTACT: Fred Guerin, Aviation Safety Engineer, 
FAA, Los Angeles Aircraft Certification Office, Airframe Branch, 3960 
Paramount Blvd., Lakewood, California 90712, telephone (562) 627-5232, 
fax (562) 627-5210.

SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 to 
include an AD for the specified model

[[Page 63055]]

helicopters was published in the Federal Register on July 29, 2004 (69 
FR 45291). That action proposed to require replacing the control 
support bracket assembly, part number (P/N) 369N2608-11, on helicopters 
that have a yaw stability augmentation system (YSAS) installed, with an 
airworthy assembly, P/N 600N2608-1. The revised time limits are 
dependent upon the time the YSAS was initially installed. Also proposed 
was revising the applicable maintenance manual to state the reduced 
life limits.
    The FAA has reviewed MD Helicopters, Inc. Service Bulletin No. 
SB600N-040, dated September 18, 2003, which describes the revised 
finite life for the control support bracket on certain serial-numbered 
helicopters, and replacing them upon reaching the revised life limit, 
or no later than November 30, 2005, whichever occurs first.
    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 the 
adoption of the rule as proposed.
    The FAA estimates that this AD will affect 13 helicopters of U.S. 
registry. Replacing the control support bracket will take approximately 
40 work hours per helicopter to accomplish at an average labor rate of 
$65 per work hour. Required parts will cost approximately $5,617 per 
helicopter. Based on these figures, the total estimated cost impact of 
this AD on U.S. operators is $106,821 to replace the control support 
bracket on each helicopter in the fleet.
    The regulations adopted herein 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the FAA, Office of the Regional Counsel, 
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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:

2004-22-12 MD Helicopters, Inc.: Amendment 39-13840. Docket No. 
2003-SW-51-AD.

    Applicability: Model 600N helicopters, serial numbers with a 
prefix of ``RN'' and numbers 025, 029, 032, 034 through 038, 040, 
041, 045, 048, or 067; or, any Model 600N helicopter with a yaw 
stability augmentation system (YSAS) installed, and with a control 
support bracket assembly, part number (P/N) 369N2608-11, installed, 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the fuselage Station 75 control support 
bracket assembly (control support bracket) and subsequent loss of 
control of the helicopter, accomplish the following:
    (a) Replace the control support bracket, part number 369N2608-
11, with an airworthy control support bracket assembly, P/N 
600N2608-1, no later than November 30, 2005, or by the time the 
helicopter reaches the hours time-in-service (TIS) listed in the 
chart below, whichever occurs first:

------------------------------------------------------------------------
                                                        Revised finite
              Helicopter serial number                    life (TIS)
------------------------------------------------------------------------
RN025...............................................                2556
RN029...............................................                2377
RN032...............................................                2498
RN034...............................................                2456
RN035...............................................                2243
RN036...............................................                2652
RN037...............................................                2544
RN038...............................................                2531
RN040...............................................                2562
RN041...............................................                2763
RN045...............................................                2015
RN048...............................................                2125
RN067...............................................                1600
------------------------------------------------------------------------


    Note: MD Helicopters, Inc. Service Bulletin No. SB600N-040, 
dated September 18, 2003, pertains to the subject of this AD.

    (b) For helicopters with a YSAS installed that are not listed in 
the previous table, replace the control support bracket, P/N 
369N2608-11, with an airworthy control support bracket, P/N 
600N2608-1, no later than November 30, 2005, or by the time the 
helicopter reaches 1,600 hours TIS since the installation of the 
YSAS.
    (c) For helicopters with no YSAS installed, but with a control 
support bracket, P/N 369N26080-11, installed, replace the control 
support bracket, with an airworthy control support bracket, P/N 
600N2608-1, prior to the installation of a YSAS.
    (d) This AD revises the Limitations section of the applicable 
maintenance manual by reducing the life limit of the control support 
bracket assembly, part number 369N2608-11, to the life limits stated 
in paragraph (a) of this AD or to 1,600 hours TIS, whichever occurs 
first.
    (e) 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 Los Angeles Aircraft Certification Office, Transport 
Airplane Directorate, FAA, for information about previously approved 
alternative methods of compliance.
    (f) This amendment becomes effective on December 3, 2004.


    Issued in Fort Worth, Texas, on October 22, 2004.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 04-24228 Filed 10-28-04; 8:45 am]
BILLING CODE 4910-13-P

The complete text was extracted from the official GovInfo HTML edition for this publication. Acquired 2026-10-09T04:01:14.677414+00:00. Text extraction preserves the recorded source wording; it does not determine current requirements.

Open the captured official edition

Source SHA-256

c9dadac49fb8ac4d74b4b74f66b18bc13a0fd3c4f10b1a5ba04f4dd39fc87b94

Text SHA-256

d52721083611a2a4924565f84eca012ad89a655294db6ec44fba4135a73cf1ac