[Federal Register Volume 64, Number 161 (Friday, August 20, 1999)]
[Rules and Regulations]
[Pages 45435-45436]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-21572]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-SW-16-AD; Amendment 39-11264; AD 99-17-18]
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 amendment adopts a new airworthiness directive (AD), 
applicable to MD Helicopters, Inc. (MDHI) Model 600N helicopters, that 
requires applying serial numbers to several life-limited components 
related to pitch control and removing and replacing the components 
according to new life-limits. This amendment is prompted by fatigue 
tests that indicate a need for shorter service lives for these 
components. The actions specified by this AD are intended to prevent 
failure of the collective pitch control tubes, collective stick 
housings, and collective pitch tube assemblies, which can cause loss of 
collective pitch control, and subsequent loss of control of the 
helicopter.

DATES: Effective September 24, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 24, 1999.

ADDRESSES: The service information referenced in this AD may be 
obtained from MD Helicopters Inc., Attn: Customer Support Division, 
5000 E. McDowell Rd., Mail Stop M615-GO48, Mesa, Arizona 85215-9797, 
telephone 1-800-388-3378 or 480-891-6342, datafax 480-891-6782. This 
information may be examined at the FAA, Office of the Regional Counsel, 
Southwest Region, Room 663, Fort Worth, Texas; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, Washington, 
DC.

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

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an AD that is 
applicable to MDHI Model 600N helicopters was published in the Federal 
Register on March 23, 1999 (64 FR 13936). That action proposed to 
require applying serial numbers to several life-limited components 
related to pitch control and removing and replacing the components 
according to new life-limits.
    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 with the following exceptions. Since 
the publication of the Notice of Proposed Rulemaking (NPRM), the name 
of the type certificate holder has changed from ``McDonnell Douglas 
Helicopter Systems'' to ``MD Helicopters, Inc.'' Also, the NPRM 
contained an error in the part number for the ``Housing, collective 
stick.'' The part number should have been ``369A7347'' but was 
incorrectly listed as ``1369A7347.'' A part number ``1369A7347'' does 
not exist for the affected model helicopter. Both the name and the part 
number have been changed in this final rule AD; the FAA has determined 
that these changes will neither increase the economic burden on any 
operator nor increase the scope of the AD.
    The FAA estimates that 16 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 0.5 work hours per 
helicopter to accomplish the required actions, and that the average 
labor rate is $60 per work hour. Based on these figures, the total cost 
impact of the AD on U.S. operators is estimated to be $480.
    The regulations adopted herein will not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    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 location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    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

    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]

    2. Section 39.13 is amended by adding a new airworthiness directive 
to read as follows:

AD 99-17-18  MD Helicopters Inc.: Amendment 39-11264. Docket No. 98-
SW-16-AD.

    Applicability: Model 600N helicopters, certificated in any 
category.

    Note 1: This AD applies to each helicopter identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise modified, altered, or repaired in the area subject to the 
requirements of this AD. For helicopters that have been modified,

[[Page 45436]]

altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (e) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the collective pitch control tubes, 
collective stick housings, and collective pitch tube assemblies, 
loss of collective pitch control, and subsequent loss of control of 
the helicopter, accomplish the following:
    (a) On or before reaching 400 hours time-in-service (TIS), apply 
the serial number (S/N) listed in McDonnell Douglas Helicopter 
Systems Mandatory Service Bulletin No. 600N-009, dated February 24, 
1998 (SB), to the two collective stick housings, P/N's 369A7347 and 
369A7820; the pilot collective pitch control tube, P/N 369A7348; and 
the co-pilot collective pitch control tube, P/N 369A7809, in the 
most visible spot for the specified aircraft S/N.
    (b) Remove and replace the following flight control components 
according to the stated life-limits:

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                             Life-Limit
                    P/N                                                                Component                                             (Hours TIS)
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369A7347..................................  Housing, collective stick.....................................................................           450
369A7348..................................  Tube, collective pitch control (pilot)........................................................           400
369H7354-3................................  Tube assembly, collective pitch (pilot).......................................................           600
369A7809..................................  Tube, collective pitch control (co-pilot).....................................................         1,800
369A7820..................................  Housing, collective stick.....................................................................           450
369H7837..................................  Housing, collective stick.....................................................................           450
369H7838-3................................  Tube assembly, collective pitch (co-pilot)....................................................         1,000
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    (c) Create a component history card or equivalent record in the 
helicopter log and record the helicopter TIS at installation for 
each of the components listed in paragraph (b) of this AD.
    (d) This AD revises the Airworthiness Limitations Section of the 
maintenance manual by reducing the life-limits of the pilot 
collective pitch control tube, the collective stick housings, and 
the collective pitch tube assemblies, and adding the co-pilot 
collective pitch control tube to the Airworthiness Limitations 
section, Component Mandatory Replacement Schedule.
    (e) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Los Angeles Aircraft Certification 
Office, FAA. Operators shall submit their requests through an FAA 
Principal Maintenance Inspector, who may concur or comment and then 
send it to the Manager, Los Angeles Aircraft Certification Office.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Los Angeles Aircraft Certification Office.

    (f) Special flight permits may be issued in accordance with 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the helicopter to a location where the 
requirements of this AD can be accomplished.
    (g) The application of serial numbers shall be done in 
accordance with the Accomplishment Instructions of McDonnell Douglas 
Helicopter Systems Mandatory Service Bulletin No. 600N-009, dated 
February 24, 1998. This incorporation by reference was approved by 
the Director of the Federal Register 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, 5000 E. McDowell Rd., Mail 
Stop M615-GO48, Mesa, Arizona 85215-9797, telephone 1-800-388-3378 
or 480-891-6342, datafax 480-891-6782. 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 Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.
    (h) This amendment becomes effective on September 24, 1999.

    Issued in Fort Worth, Texas, on August 12, 1999.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-21572 Filed 8-19-99; 8:45 am]
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