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

[Federal Register Volume 64, Number 120 (Wednesday, June 23, 1999)] [Proposed Rules] [Pages 33447-33448] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-15932]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-SW-80-AD]

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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) applicable to MD Helicopters Inc. (MDHI) Model 369D, 369E, 369FF, 500N, and 600N helicopters. The AD would require replacing the oil cooler blower bracket (bracket). This proposal is prompted by three reports of cracked brackets. The actions specified by the proposed AD are intended to prevent failure of a bracket, loss of cooling of engine oil and transmission oil, and a subsequent forced landing.

DATES: Comments must be received on or before August 23, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 98-SW-80-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

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:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket No. 98-SW-80-AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 98-SW-80-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Discussion

This document proposes the adoption of a new AD, applicable to MDHI Model 369D, 369E, 369FF, 500N, and 600N helicopters. The AD would require replacing the bracket, part number (P/N) 369F5190-1 with an airworthy bracket, P/N 369F5194-1. This proposal is prompted by three reports of cracked brackets. The actions specified by the proposed AD are intended to prevent failure of a bracket, loss of cooling of engine oil and transmission oil, and a subsequent forced landing. The FAA has reviewed Boeing Service Bulletin SB369D-196 SB369E-089 SB369F-076 SB500N-016 SB600N-012, dated April 28, 1998, which describes procedures for removing affected brackets and replacing them with improved-design brackets. Since an unsafe condition has been identified that is likely to exist or develop on other MDHI Model 369D, 369E, 369FF, 500N, and 600N helicopters of the same type design, the proposed AD would require removing the bracket, P/N 369F5190-1, and replacing it with an airworthy bracket, P/N 369F5194-1. The FAA estimates that 100 helicopters of U.S. registry would be affected by this proposed AD, that it would 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 would cost approximately $225 per helicopter. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $37,500. The regulations proposed herein would 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 proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this proposed regulation (1) Is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT

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Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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:

MD Helicopters Inc. (MDHI): 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) 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 when approved by the Manager, Los Angeles Aircraft Certification Office. 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.

(c) 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. Issued in Fort Worth, Texas, on June 17, 1999. Henry A. Armstrong, Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 99-15932 Filed 6-22-99; 8:45 am] BILLING CODE 4910-13-U