Airworthiness directives: Boeing,

[Federal Register: July 20, 1999 (Volume 64, Number 138)]

[Proposed Rules]

[Page 38846-38848]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr20jy99-20]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-NM-89-AD]

RIN 2120-AA64

Airworthiness Directives; Boeing Model 757-200 and -300 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 757-200 and - 300 series airplanes. This proposal would require modification of the slide/raft evacuation system by installing a girt reinforcement chafing patch. This proposal is prompted by reports of holes in the inflatable area of the slide/raft evacuation system. The actions specified by the proposed AD are intended to prevent holes in the inflatable portion of the slide/raft evacuation system, which could result in the slide/raft being unusable as a raft during an emergency water landing.

DATES: Comments must be received by September 3, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-89-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from Air Cruisers Company, Technical Publications Department, P.O. Box 180, Belmar, New Jersey 07719-0180. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Keith Ladderud, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2780; fax (425) 227-1181.

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 shall 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 filedin 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 Number 99-NM-89-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, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-89-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports of holes in the inflatable portion of certain slide/

[[Page 38847]]

raft evacuation systems on Boeing Model 757-200 and -300 series airplanes. The holes result from chafing of the slide/raft on a bracket harness assembly used to attach the system to the aircraft door. This condition, if not corrected, could result in the slide/raft being unusable as a raft during an emergency water landing.

Explanation of Relevant Service Information

The FAA has reviewed and approved Air Cruisers Company Service Bulletin 757-105-25-51, dated January 29, 1999, which describes procedures for modifying the slide/raft evacuation system by installing a girt reinforcement patch in the area prone to chafing against the bracket harness assembly. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions specified in the service bulletin described previously, except as discussed below.

Differences Between the Proposed Rule and Service Bulletin

Operators should note that this proposed AD would require modification of the slide/raft within 36 months after the effective date of this AD. The service bulletin recommends that this action should be accomplished, ``* * * at the next regular scheduled maintenance to the equipment.'' In developing an appropriate compliance time for this AD, the FAA considered not only the manufacturer's recommendation, but the degree of urgency associated with addressing the subject unsafe condition, the average utilization of the affected fleet, and the time necessary to perform the modification (5 hours per airplane). In light of all of these factors, the FAA finds a 36-month compliance time for initiating the required actions to be warranted, in that it represents an appropriate interval of time allowable for affected airplanes to continue to operate without compromising safety.

Cost Impact

There are approximately 445 airplanes of the affected design in the worldwide fleet. The FAA estimates that 310 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 5 work hours per airplane to accomplish the proposed modification, and that the average labor rate is $60 per work hour. Required parts would cost approximately $145 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $137,950, or $445 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

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 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 the following new airworthiness directive:

   Boeing: Docket 99-NM-89-AD.

   Applicability: Model 757-200 and -300 series airplanes, equipped with Air Cruisers Company slide/raft evacuation systems having part and serial numbers identified in Table 1 of this AD; certificated in any category.

   Table 1.--Air Cruisers Company Slide/Raft Evacuation Systems Subject to this AD

   Name

   Part No.

   Serial Nos.

   Air Cruisers.................. D30657-( )

   Prior to 1132. Air Cruisers.................. D30658-( )

   Prior to 0859. Air Cruisers.................. D30659-( )

   Prior to 0860. Air Cruisers.................. 61570-( )

   Prior to 0321. Air Cruisers.................. 61475-( )

   Prior to 0137. Air Cruisers.................. 61475-( )

   0138, 0139.

   Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes 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 (c) 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 holes in the inflatable portion of the slide/raft evacuation system, which

   [[Page 38848]]

   could result in the slide/raft being unusable as a raft during an emergency water landing, accomplish the following:

   (a) Within 36 months after the effective date of this AD, modify the slide/raft evacuation system in accordance with Air Cruisers Company Service Bulletin 757-105-25-51, dated January 29, 1999.

   (b) As of the effective date of this AD, no person shall install a slide/raft evacuation system having a part number and serial number identified in Table 1 of this AD, on any airplane, unless that slide/raft evacuation system has been modified in accordance with Air Cruisers Company Service Bulletin 757-105-25-51, dated January 29, 1999.

   Alternative Methods of Compliance

   (c) 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, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

   Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

   Special Flight Permits

   (d) 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 airplane to a location where the requirements of this AD can be accomplished.

   Issued in Renton, Washington, on July 14, 1999. D.L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 99-18412Filed7-19-99; 8:45 am]

   BILLING CODE 4910-13-U