Airworthiness Directives; MD Helicopters Inc. Model 369D, D369E, 369FF, 500N, and 600N Helicopters

[Federal Register Volume 64, Number 189 (Thursday, September 30, 1999)]
[Rules and Regulations]
[Pages 52649-52650]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-25375]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-SW-80-AD; Amendment 39-11342; AD 99-20-12]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters Inc. Model 369D, D369E, 
369FF, 500N, and 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. Model 369D, 369E, 369FF, 500N, and 
600 N helicopters, that requires replacing the oil cooler blower 
bracket (bracket). This amendment is prompted by three reports of 
cracked brackets. The actions specified by this AD are intended to 
prevent failure of a bracket, loss of cooling of engine oil and 
transmission oil, and subsequent forced landing.

EFFECTIVE DATE: November 4, 1999.

FOR FURTHER INFORMATION CONTACT: Bruce Conze, Aerospace Engineer, FAA, 
Los Angeles Aircraft, Certification Office, 3960 Paramount Blvd, 
Lakewood, California 90712, telephone (562) 627-5261, fax (562) 627-
5210.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to MD Helicopters Inc. Model 369D, 
369E, 369FF, 500N, and 600N helicopters was published in the Federal 
Register on June 23, 1999 (64 FR 33447). That action proposed to 
require replacing the bracket.
    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 100 helicopters of U.S. registry will be 
affected by this AD, that it will take approximately 2.5 work hours per 
helicopter to replace the bracket, and that the average labor rate is 
$60 per work hour. Required parts will cost approximately $225 per 
helicopter. Based on these figures, the total cost impact of the AD on 
U.S. operators is estimated to be $37,500.
    The regulations adopted therein 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 FAA, Office of the Regional Counsel, 
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 
76137.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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 99-20-12 MD Helicopters, Inc. (MDHI): Amendment 39-11342. Docket 
No. 98-SW-80-AD.

    Applicability: Model 369D, 369E, 369FF, 500N, and 600N 
helicopters, with oil cooler blower bracket (bracket), part number 
(P/N)

[[Page 52650]]

369F5190-1, installed, 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, 
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 (b) 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 within 100 hours time-in-service, unless 
accomplished previously.
    To prevent failure of a bracket, loss of cooling of engine oil 
and transmission oil, and a subsequent forced landing, accomplish 
the following:
    (a) Remove the bracket, P/N 369F5190-1, and replace it with an 
airworthy bracket P/N 369F5194-1.
    (b) 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. Operators shall submit their request 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.

    (c) Special flight permits may be issued in accordance with 
sections 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.
    (d) This amendment becomes effective on November 4, 1999.

    Issued in Fort Worth, Texas, on September 22, 1999.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-25375 Filed 9-29-99; 8:45 am]
BILLING CODE 4910-13-M

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