[Federal Register Volume 59, Number 169 (Thursday, September 1, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-21581]


[[Page Unknown]]

[Federal Register: September 1, 1994]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-80-AD]

 

Airworthiness Directives; Boeing Model 737 Series Airplanes

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 Boeing Model 737 series 
airplanes. This proposal would require modification of certain number 2 
galley upper attachment support structure. This proposal is prompted by 
results of engineering tests and analyses which revealed that certain 
upper attachment support structure of the number 2 galley is unable to 
support certain loads that may occur during emergency landing 
conditions. If the galley support breaks, the galley may shift and 
cause blockage of the forward service door. The actions specified by 
the proposed AD are intended to prevent inability of passengers and 
crew to exit the airplane through this door after an emergency landing.

DATES: Comments must be received by October 27, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-80-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal 
holidays. -
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Thomas Rodriguez, Aerospace Engineer, 
Airframe Branch, ANM-120S, Seattle Aircraft Certification Office, FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (206) 227-2779; fax (206) 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 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-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, Transport Airplane Directorate, ANM-103, Attention: Rules 
Docket No. 94-NM-80-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion -

    The FAA has received results of engineering tests and subsequent 
analyses, which revealed that certain number 2 galley upper attachment 
structure will not support loads generated under emergency landing 
conditions. Airplanes having rectangular airplane intercostal support 
structure from Body Station (BS) 344 to BS 360 (inclusive) with number 
2 galleys exceeding 1,170 pounds (including any attached equipment that 
may impose loads on the galley), or airplanes having triangular 
intercostal support structure from BS 344 to BS 360 (inclusive) with 
number 2 galleys exceeding 1,050 pounds (including any attached 
equipment which may impose loads on the galley) will not support the 
load generated under emergency landing conditions as specified by the 
Federal Aviation Regulations (FAR). If the galley support structure 
breaks, the galley may shift and cause blockage of the forward service 
door. This condition, if not corrected, could result in the inability 
of passengers and crew to exit the airplane using the galley door after 
an emergency landing. -
    The FAA has reviewed and approved Boeing Service Bulletin 737-53-
1154, dated November 11, 1993, which describes procedures for adding 
new shear ties to the BS 360 frame and changing the intercostals 
between BS 344 and BS 360 (inclusive) on certain airplanes. The purpose 
of this modification is to strengthen the airplane support structure 
when the weight of galley number 2 exceeds limits described in the 
service bulletin. Accomplishment of the actions described in this 
service bulletin will ensure that the galley support structure can 
withstand 9G forward load in the event of an emergency landing. -
    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 modification of the airplane support 
structure from BS 344 to BS 360 (inclusive) for airplanes where the 
number 2 galley exceeds certain weight limits. The actions would be 
required to be accomplished in accordance with the service bulletin 
described previously. -
    There are approximately 613 Model 737 series airplanes of the 
affected design in the worldwide fleet. The FAA estimates that 139 
airplanes of U.S. registry would be affected by this proposed AD, that 
it would take approximately 64 work hours per airplane to accomplish 
the proposed actions, and that the average labor rate is $55 per work 
hour. Required parts would cost approximately $1,205 per airplane. 
Based on these figures, the total cost impact of the proposed AD on 
U.S. operators is estimated to be $656,775, or $4,725 per airplane. -
    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:

Boeing: Docket 94-NM-80-AD.

    -Applicability: Model 737 series airplanes; as listed in Boeing 
Service Bulletin 737-53-1154, dated November 11, 1993; equipped with 
rectangular intercostal support structures from Body Station (BS) 
344 to BS 360 (inclusive) and a number 2 galley weight exceeding 
1,170 pounds (including any attached equipment that imposes loads on 
the galley), or equipped with triangular intercostal support 
structures from BS 344 to BS 360 (inclusive) and a number 2 galley 
weight exceeding 1,050 pounds (including any attached equipment that 
imposes loads on the galley); certificated in any category. -
    Compliance: Required as indicated, unless accomplished 
previously. -
    To prevent inability of passengers and crew to exit the forward 
service door during an emergency landing condition, accomplish the 
following: -
    (a) Within 18 months after the effective date of this AD, modify 
the airplane support structure from BS 344 to BS 360 (inclusive), in 
accordance with Boeing Service Bulletin 737-53-1154, dated November 
11, 1993. -
    (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, 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: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

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

    Issued in Renton, Washington, on August 26, 1994.
N.B. Martenson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-21581 Filed 8-31-94; 8:45 am]
BILLING CODE 4910-13-U