[Federal Register Volume 65, Number 251 (Friday, December 29, 2000)]
[Proposed Rules]
[Pages 82957-82959]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-33344]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-308-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-300, 737-400, 737-500, 
737-600, 737-700, 737-800, 757-200, 757-200PF, 757-200CB, and 757-300 
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 would apply to certain Boeing Model 737-300, 737-
400, 737-500, 737-600, 737-700, 737-800, 757-200, 757-200PF, 757-200CB, 
and 757-300 series airplanes. This proposal would require a test of the 
two electrical circuits that close the fuel shutoff valve on the wing 
spar, and repair, if necessary. This action is necessary to prevent 
inability to shut off the flow of fuel to an engine after an 
uncontained engine failure, which could result in a fire spreading to 
other parts of the airplane. This action is intended to address the 
identified unsafe condition.

DATES: Comments must be received by February 12, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-308-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. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-308-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    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: Kathrine Rask, Aerospace Engineer, 
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification 
Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone 
(425) 227-1547; 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 action may be changed in 
light of the comments received.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    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.

[[Page 82958]]

    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-308-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. 2000-NM-308-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report indicating that the functional test 
performed during production of certain Boeing Model 737-300, 737-400, 
737-500, 737-600, 737-700, 737-800, 757-200, 757-200PF, 757-200CB, and 
757-300 series airplanes is not adequate to ensure that two electrical 
circuits that close the fuel shutoff valve on the wing spar can both 
supply electrical power to the fuel shutoff valve. Investigation 
revealed three airplanes in service that had wiring problems. The 
functional test only verifies that the fuel shutoff valve operates 
correctly, and only one of the two circuits needs to supply power for 
the fuel shutoff valve to operate correctly. The design incorporates 
two separate electrical circuits that close the fuel shutoff valve to 
ensure that, if one circuit is severed by debris from an uncontained 
engine failure, one circuit will still be available so that fuel can be 
shut off from the failed engine. However, if only one of the two 
electrical circuits that close the fuel shutoff valve is supplying 
power, and it is severed as a result of an uncontained engine failure, 
the flight crew will be unable to shut off the flow of fuel to the 
failed engine. This condition, if not corrected, could result in a fire 
spreading to other parts of the airplane.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Special Attention Service 
Bulletin 737-28-1164, dated August 24, 2000, which applies to certain 
Boeing Model 737-300, 737-400, and 737-500 series airplanes. That 
service bulletin describes a one-time test of the two electrical 
circuits that close the fuel shutoff valve on each wing spar to 
determine if there is continuity. The service bulletin also notes what 
procedures to use to locate and repair any discontinuity.
    The FAA has also reviewed and approved the following service 
bulletins, all dated October 26, 2000:
     Boeing Special Attention Service Bulletin 737-28-1160, 
Revision 1 (which applies to certain Boeing Model 737-600, 737-700, and 
737-800 series airplanes).
     Boeing Special Attention Service Bulletin 757-28-0060, 
Revision 1 (which applies to certain Boeing Model 757-200, 757-200PF, 
and 757-200CB series airplanes).
     Boeing Special Attention Service Bulletin 757-28-0061, 
Revision 1 (which applies to certain Boeing Model 757-300 series 
airplanes).
    These service bulletins describe procedures for a one-time test to 
measure the voltage of the two electrical circuits that close the fuel 
shutoff valve on the wing spar, and specify appropriate procedures to 
be used if inappropriate voltage is found.
    Accomplishment of the actions specified in the applicable 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 applicable service bulletin described previously.

Cost Impact

    There are approximately 3,403 airplanes of the affected design in 
the worldwide fleet.
    The FAA estimates that this proposed AD would affect 795 Model 737-
300, -400, and -500 airplanes of U.S. registry. The proposed test would 
take approximately 1 work hour on each of these airplanes, at an 
average labor rate of $60 per work hour. Based on these figures, the 
FAA estimates the cost impact of the proposed AD on U.S. operators of 
these airplanes to be $47,700, or $60 per airplane.
    The FAA estimates that this proposed AD would affect 820 Model 737-
600, 737-700, 737-800, 757-200, 757-200PF, 757-200CB, and 757-300 
airplanes of U.S. registry. The proposed test would take approximately 
3 work hours on each of these airplanes, at an average labor rate of 
$60 per work hour. Based on these figures, the FAA estimates the cost 
impact of the proposed AD on U.S. operators of these airplanes to be 
$147,600, or $180 per airplane.
    The cost impact figures discussed above are 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 proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up, planning time, or time 
necessitated by other administrative actions.

Regulatory Impact

    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 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 2000-NM-308-AD.


[[Page 82959]]


    Applicability: The following models and series of airplanes as 
listed in the service bulletins below, certificated in any category:

------------------------------------------------------------------------
        Airplane model         Boeing special attention service bulletin
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737-300, 737-400, 737-500....  737-28-1164, dated August 24, 2000.
737-600, 737-700, 737-800....  737-28-1160, Revision 1, dated October
                                26, 2000.
757-200, 757-200PF, 757-200CB  757-28-0060, Revision 1, dated October
                                26, 2000.
757-300......................  757-28-0061, Revision 1, dated October
                                26, 2000.
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    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 (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 as indicated, unless accomplished 
previously.
    To prevent inability to shut off the flow of fuel to an engine 
after an uncontained engine failure, which could result in a fire 
spreading to other parts of the airplane, accomplish the following:

Test and Repair

    (a) Within 6 months after the effective date of this AD, perform 
a test to determine if there is continuity or to measure voltage, as 
applicable, of the two electrical circuits that close the fuel 
shutoff valve on the wing spar. Do the test per Boeing Special 
Attention Service Bulletin 737-28-1164, dated August 24, 2000 (for 
Boeing Model 737-300, 737-400, and 737-500 series airplanes); or 
Boeing Special Attention Service Bulletin 737-28-1160, Revision 1 
(for Boeing Model 737-600, 737-700, and 737-800 series airplanes); 
Boeing Special Attention Service Bulletin 757-28-0060, Revision 1 
(for Boeing Model 757-200, 757-200PF, and 757-200CB series 
airplanes); or Boeing Special Attention Service Bulletin 757-28-
0061, Revision 1 (for Boeing Model 757-300 series airplanes); all 
dated October 26, 2000; as applicable.
    (1) For Boeing Model 737-300, 737-400, and 737-500 series 
airplanes: If any discontinuity is detected, prior to further 
flight, repair per Boeing Special Attention Service Bulletin 737-28-
1164.
    (2) For airplane models other than those listed in paragraph 
(a)(1) of this AD: If any measurement is not between 21 and 34 volts 
DC, prior to further flight, repair per the applicable service 
bulletin.

    Note 2: Tests accomplished per Boeing Special Attention Service 
Bulletin 737-28-1160 (for Boeing Model 737-600, 737-700, and 737-800 
series airplanes), dated June 5, 2000; Boeing Special Attention 
Service Bulletin 757-28-0060 (for Boeing Model 757-200, 757-200PF, 
and 757-200CB series airplanes), dated June 15, 2000; or Boeing 
Special Attention Service Bulletin 757-28-0061, dated June 15, 2000 
(for Boeing Model 757-300 series airplanes); as applicable; are 
acceptable for compliance with paragraph (a) of this AD.

Alternative Methods of Compliance

    (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. 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 3: 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

    (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 December 22, 2000.
John J. Hickey,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-33344 Filed 12-28-00; 8:45 am]
BILLING CODE 4910-13-P