Skip to Content

Proposed Rule

Airworthiness Directives; Sikorsky Aircraft Corporation Model S76A, B, and C Helicopters

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble Start Printed Page 6382

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S76A, B, and C helicopters. The AD would require removing non-conforming main landing gear brake discs (discs) and replacing them with different part-numbered airworthy discs. It would also require revising the Rotorcraft Flight Manual (RFM) to adjust takeoff and landing distances until the discs are replaced. This proposal is prompted by the manufacture of some discs using inferior materials. The actions specified by the proposed AD are intended to prevent reduced braking performance and subsequent loss of control of the helicopter.

DATES:

Comments must be received on or before April 8, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 2002-SW-39-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. You may also send comments electronically to the Rules Docket at the following address: 9-asw-adcomments@faa.gov. Comments may be inspected at the Office of the Regional Counsel between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Terry Fahr, Aviation Safety Engineer, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, MA 01803, telephone (781) 238-7155, fax (781) 238-7199.

End Further Info End Preamble Start Supplemental Information

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 will be considered before taking action on the proposed rule. The proposals contained in this document 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 mailed comments submitted in response to this proposal must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. 2002-SW-39-AD.” The postcard will be date stamped and returned to the commenter.

Discussion

This document proposes the adoption of a new AD for Sikorsky Model S76A, B, and C helicopters that would require, within 60 days, determining if discs, part number (P/N) 5014067, are installed. If so, replacing them with discs, P/N 5007672, and re-identifying brake assembly, P/ N 5007555 and P/N 5007555-1, as brake assembly P/N 5007555-3, and brake assembly, P/N 5007555-2, as brake assembly, P/N 5007555-4, is required within 90 days. The proposed AD would also require revising the RFM to adjust the Category A rejected takeoff distance, the Category A landing distance, and the Category B landing distance by multiplying the distance by 1.67 to obtain the corrected distance until the discs are replaced. This proposal is prompted by the manufacture of some discs using inferior materials, resulting in degraded braking performance. The actions specified by the proposed AD are intended to prevent reduced braking performance and subsequent loss of control of the helicopter. Removing the discs, P/N 5014067, and replacing them with discs, P/N 5007672, would be a terminating action for the requirements of the proposed AD.

The FAA has reviewed Sikorsky Aircraft Corporation Alert Service Bulletin (ASB) No. 76-32-27, dated April 30, 2002, which contains Aircraft Braking Systems Corporation ASB S76-32-A24, dated April 10, 2002; and Sikorsky Aircraft Corporation ASB No. 76-32-28, dated May 17, 2002, which contains Aircraft Braking Systems Corporation ASB S76-32-A25, dated May 15, 2002. The ASB's describe procedures for replacing any non-conforming discs, reidentifying brake assemblies, and revising takeoff and landing distances in the RFM until the discs are replaced.

This unsafe condition is likely to exist or develop on other helicopters of the same type designs. Therefore, the proposed AD would require, within 60 days, determining if non-conforming discs are installed, and if so, replacing them within 90 days with airworthy discs, P/N 5007672. It would also require revising the RFM to increase the takeoff and landing distances for helicopters with non-conforming discs installed until the discs are replaced. The actions would be required to be accomplished in accordance with the alert service bulletins described previously.

The FAA estimates that 180 helicopters of U.S. registry would be affected by this proposed AD, that it would take approximately 0.5 work hour per helicopter to determine if non-conforming discs are installed, and 1.25 work hours per helicopter to remove and replace and re-identify any non-conforming discs. The average labor rate is $60 per work hour. Required parts would cost approximately $1,902 per disc, and there are two discs per helicopter. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $703,620 to replace the discs throughout the fleet.

The regulations proposed herein would 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 proposal would not have federalism implications under Executive Order 13132.

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 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 Start Printed Page 6383location provided under the caption ADDRESSES.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

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:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

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

Sikorsky Aircraft Corporation: Docket No. 2002-SW-39-AD.

Applicability: Model S76A, B, and C helicopters, with main landing gear brake assembly (brake assembly), part number (P/N) 5007555, 5007555-1, or 5007555-2 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 (d) 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 reduced braking performance and subsequent loss of control of the helicopter, accomplish the following:

(a) Within 60 days, determine if a main landing gear brake disc (disc), part number (P/N) 5014067, is installed in the braking assembly in accordance with:

(1) Section III-Accomplishment Instructions, paragraph 1.A. through 1.D., of Aircraft Braking Systems Corporation Alert Service Bulletin S76-32-A24, dated April 10, 2002 (ASB A24) for braking assembly, P/N 5007555 and P/N 5007555-1, and

(2) Section III-Accomplishment Instructions, paragraph 1.A. and 1.B., of Aircraft Braking Systems Corporation Alert Service Bulleting S76-32-A25, dated May 15, 2002 (ASB A25), for braking assembly, P/N 5007555-2.

(b) If disc, P/N 5014067, is installed, within 90 days, remove that disc and replace it with disc, P/N 5007672, and re-identify:

(1) Brake assembly, P/N 5007555 and P/N 5007555-1, as brake assembly, P/N 5007555-3, in accordance with the conversion of brake assembly instructions on page 6 of ASB A24, and

(2) Brake assembly, P/N 5007555-2, as brake assembly, P/N 5007555-4, in accordance with the conversion of brake assembly instructions on page 6 of ASB A25.

Note 2:

Sikorsky Aircraft Corporation ASB No. 76-32-27, dated April 30, 2002, contains Aircraft Braking Systems Corporation ASB S76-32-A24, dated April 10, 2002, and Sikorsky Aircraft Corporation ASB No. 76-32-28, dated May 17, 2002, contains Aircraft Braking Systems Corporation ASB S76-32-A25, dated May 15, 2002.

(c) Until all installed discs, P/N 5014067, on the helicopter are replaced with disc, P/N 5007672, and all brake assemblies are re-identified in accordance with paragraph (b) of this AD, before further flight, increase the Category A-Rejected Takeoff Distance, the Category A-Landing Distance, and the Category B-Landing Distance as stated in the current Rotorcraft Flight Manual (RFM) by multiplying these rejected takeoff and landing distances by a factor of 1.67.

Note 3:

There are temporary revisions to the RFM available from the helicopter manufacturer that documents increased rejected takeoff and landing distances.

(d) 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, Boston Aircraft Certification Office, Engine and Propeller Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Boston Aircraft Certification Office.

Note 4:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Boston Aircraft Certification Office.

(e) Special flight permits may be issued in accordance with 14 CFR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished.

Start Signature

Issued in Fort Worth, Texas, on January 29, 2003.

David A. Downey,

Manager, Rotorcraft Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 03-3031 Filed 2-6-03; 8:45 am]

BILLING CODE 4910-13-P