[Federal Register Volume 59, Number 103 (Tuesday, May 31, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-13137]


[[Page Unknown]]

[Federal Register: May 31, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-73-AD]

 

Airworthiness Directives; Pacific Scientific Company, HTL/KIN-
TECH Division, Lap Belt Assemblies and Restraint Systems

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) that is applicable to certain Pacific Scientific lap 
belt assemblies and restraint systems. This proposal would require 
removal of certain lap belt assemblies and restraint systems, and 
replacement with another design assembly. This proposal is prompted by 
a report indicating that, subsequent to an accident involving a 
transport category airplane, some passengers experienced difficulty in 
attempting to release the buckle on their lap belts. The actions 
specified by the proposed AD are intended to prevent the inability of 
passengers or crew to egress from their seats during an emergency 
situation, due to problems associated with the lap belt assembly.

DATES: Comments must be received by July 25, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-73-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 Pacific Scientific, HTL/KIN-TECH Division, 22715 Savi 
Ranch Parkway, Yorba Linda, California 92687. This information may be 
examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, 
SW., Renton, Washington; or at the FAA, Los Angeles Aircraft 
Certification Office, Transport Airplane Directorate, 3229 East Spring 
Street, Long Beach, California.

FOR FURTHER INFORMATION CONTACT: Layton Walker, Aerospace Engineer, 
Systems & Equipment Branch, ANM-130L, Los Angeles Aircraft 
Certification Office, FAA, Transport Airplane Directorate, 3229 East 
Spring Street, Long Beach, California 90806-2425; telephone (310) 988-
5339; fax (310) 988-5210.

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 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 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 Number 94-NM-73-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-103, Attention: Rules 
Docket No. 94-NM-73-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion -

    In January 1994, an accident involving a Jetstream Model J4101 
airplane occurred in which several surviving passengers experienced 
difficulty in removing their lap belts. One passenger indicated that 
the plastic release lever on the buckle was difficult to operate and 
had to be moved greater than 90 degrees before it would release. The 
airplane was destroyed in the post-crash fire, so no evaluation could 
be made of the specific lap belts in question. However, the 
manufacturer of the lap belt assembly was able to duplicate this 
problem at its facility, using a lap belt tester with foam padding 
added to simulate soft abdominal flesh. This examination revealed that 
the existing buckle design is such that the connector half, when 
inserted into the buckle portion, is retained by a raised portion of 
the buckle frame. This raised portion is angled 90 degrees to the floor 
of the buckle frame. Activation of the buckle lever does not unlatch 
the belt, as is common in other designs; rather, activation of the 
buckle lever allows the connector to be manually moved up off the 
raised portion of the buckle frame and, thus, disconnected. This 
disconnecting movement is easily accomplished when done under normal 
operating conditions; however, when attempted under certain load 
conditions and without prior knowledge of this unique design feature, 
the buckle will not release and no amount of lever movement will cause 
it to release. This condition, if not corrected, could result in 
difficulty for passengers or crew to egress from their seats in an 
emergency situation. -
    The subject seat buckles have part numbers 1108435 and 1108460; 
both are approved under Technical Standard Order (TSO)-C22f. The lap 
belt assemblies and restraint systems in which they are used can be 
installed on any type of aircraft or rotorcraft. -
    The FAA has reviewed and approved Pacific Scientific Service 
Bulletin 1108435-25-01, dated April 28, 1994, which describes 
procedures for replacing passenger and crew lap belts and restraint 
systems that incorporate the P/N 1108435 ``45 degrees'' release lift 
lever buckle assembly. The replacement assembly has a modified design 
that will improve the lap belt buckle release feature. -
    Additionally, the FAA also has reviewed and approved Pacific 
Scientific Service Bulletin 1108460-25-01, dated April 28, 1994, which 
describes procedures for replacing passenger and crew lap belts and 
restraint systems that incorporate the P/N 1108460 ``90 degrees'' 
release lift lever buckle assembly. This replacement assembly likewise 
has a modified design that will improve the lap belt buckle release 
feature. -
    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 replacement of the subject lap belt 
assemblies and restraint systems with new design assemblies. The 
actions would be required to be accomplished in accordance with the 
service bulletins described previously. -
    There are approximately 27,002 lap belts of the affected design 
installed in aircraft and rotorcraft worldwide. The FAA estimates that, 
of this number, approximately 10,000 could be installed on U.S. 
registered aircraft and rotorcraft. It would take approximately .5 work 
hour per lap belt to accomplish the proposed actions, at an average 
labor rate of $55 per work hour. Required parts would be supplied by 
Pacific Scientific Company at no cost to operators. Based on these 
figures, the total cost impact of the proposed AD on U.S. operators is 
estimated to be $275,000, or $27.50 per lap belt. -
    The total 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. -
    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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
106(g); and 14 CFR 11.89.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

Pacific Scientific Company, HTL/Kin-tech Division: Docket 94-NM-73-
AD.

    Applicability: Lap belt assemblies and restraint systems, as 
listed in Pacific Scientific Service Bulletin 1108435-25-01, dated 
April 28, 1994, and Pacific Scientific Service Bulletin 1108460-25-
01, dated April 28, 1994; as installed on aircraft and rotorcraft, 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent the inability of passengers or crew to egress from 
their seats during an emergency situation, due to problems 
associated with the lap belt assembly, accomplish the following:
    (a) Within 90 days after the effective date of this AD, remove 
the applicable lap belt assemblies and restraint systems, and 
replace them with new design assemblies in accordance with Pacific 
Scientific Service Bulletin 1108435-25-01, dated April 28, 1994, or 
Pacific Scientific Service Bulletin 1108460-25-01, dated April 28, 
1994, as applicable.
    (b) As of a date 90 days after the effective date of this AD, no 
person shall install on any aircraft or rotorcraft a passenger or 
crew lap belt or restraint system (as listed in Pacific Scientific 
Service Bulletin 1108435-25-01, dated April 28, 1994, and Pacific 
Scientific Service Bulletin 1108460-25-01, dated April 28, 1994) 
that incorporates the part number 1108435 ``45 degrees'' release 
lift lever buckle assembly, or the part number 1108460 ``90 
degrees'' release lift lever buckle assembly.
    (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, Los Angeles 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, Los Angeles ACO.

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

    (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 May 24, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-13137 Filed 5-27-94; 8:45 am]
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