[Federal Register Volume 59, Number 240 (Thursday, December 15, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-30805]


[[Page Unknown]]

[Federal Register: December 15, 1994]


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DEPARTMENT OF TRANSPORTATION
14 CFR Part 39

[Docket No. 94-NM-177-AD]

 

Airworthiness Directives; Boeing Model 727 and 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 727 and Model 
737 series airplanes. This proposal would require replacement of the 
actuator of the engine fuel shutoff valve and the fuel system crossfeed 
valve with an improved actuator. This proposal is prompted by reports 
indicating that, during ground acceptance tests on Model 737 series 
airplanes, the actuator clutch on the engine shutoff and crossfeed 
valves slipped at cold temperatures due to improper functioning. The 
actions specified by the proposed AD are intended to prevent improper 
functioning of these actuators, which could result in a fuel imbalance 
due to the inability of the flightcrew to transfer fuel through the 
crossfeed valve; improperly functioning actuators could also prevent 
the pilot from shutting off the fuel to the engine following an engine 
failure and/or fire.

DATES: Comments must be received by February 10, 1995.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-103, 
Attention: Rules Docket No. 94-NM-177-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: Stephen S. Bray, Aerospace Engineer, 
Propulsion Branch, ANM-141S, FAA, Transport Airplane Directorate, 
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056; telephone (206) 227-2681; 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-177-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-177-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that, during ground 
acceptance tests on Model 737 series airplanes, the actuator clutch on 
the engine shutoff and crossfeed valves slipped at temperatures below -
23 F. Subsequent testing, conducted by J. C. Carter Company (the 
manufacturer of the engine shutoff and crossfeed valves), revealed that 
the actuator clutch slipped at cold temperatures when the engine 
shutoff valve was commanded to either the ``close'' or ``open'' 
position. Such a condition prevents the operation of the engine shutoff 
and crossfeed valves. Improper functioning of these actuators, if not 
corrected, could result in a fuel imbalance due to the inability of the 
flightcrew to transfer fuel through the crossfeed valve, or could 
prevent the pilot from shutting off the fuel to the engine following an 
engine failure and/or fire.
    The subject actuators are also installed on certain Model 727 
series airplanes. Therefore, those Model 727 series airplanes are 
subject to the same unsafe condition identified on Model 737 series 
airplanes.
    The FAA has reviewed and approved J. C. Carter Company Service 
Bulletin 61163-28-08, dated September 1, 1994, which describes 
procedures for replacement of the actuator, having part number (P/N) 
40574-2 (Model EM487-3), with a new actuator, having P/N 40574-4 (Model 
EM487-4).
    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 actuator of the engine 
fuel shutoff valve and the fuel system crossfeed valve with a new 
actuator. The actions would be required to be accomplished in 
accordance with the service bulletin described previously.
    As a result of recent communications with the Air Transport 
Association (ATA) of America, the FAA has learned that, in general, 
some operators may misunderstand the legal effect of AD's on airplanes 
that are identified in the applicability provision of the AD, but that 
have been altered or repaired in the area addressed by the AD. The FAA 
points out that all airplanes identified in the applicability provision 
of an AD are legally subject to the AD. If an airplane has been altered 
or repaired in the affected area in such a way as to affect compliance 
with the AD, the owner or operator is required to obtain FAA approval 
for an alternative method of compliance with the AD, in accordance with 
the paragraph of each AD that provides for such approvals. A note has 
been included in this notice to clarify this requirement.
    There are approximately 4,137 Model 727 and Model 737 series 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 2,190 airplanes of U.S. registry would be affected by 
this proposed AD, that it would take approximately 3 work hours per 
airplane to accomplish the proposed actions, and that the average labor 
rate is $60 per work hour. Required parts would be supplied by J.C. 
Carter Company at no cost to the operators. Based on these figures, the 
total cost impact of the proposed AD on U.S. operators is estimated to 
be $394,200, or $180 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-177-AD.

    Applicability: Model 727 and Model 737 series airplanes, as 
listed in J. C. Carter Company Service Bulletin 61163-28-08, dated 
September 1, 1994, certificated in any category.

    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 use the authority 
provided in paragraph (b) to request approval from the FAA. This 
approval may address either no action, if the current configuration 
eliminates the unsafe condition; or different actions necessary to 
address the unsafe condition described in this AD. Such a request 
should include an assessment of the effect of the changed 
configuration on the unsafe condition addressed by this AD. In no 
case does the presence of any modification, alteration, or repair 
remove any airplane from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent improper functioning of certain actuators, which 
could result in a fuel imbalance due to the inability of the 
flightcrew to transfer fuel through the crossfeed valve, or which 
could prevent the pilot from shutting off the fuel to the engine 
following an engine failure and/or fire, accomplish the following:
    (a) Within 24 months after the effective date of this AD, 
replace the actuator, having part number (P/N) 40574-2 (Model EM487-
3), on the fuel system crossfeed valve and the engine shutoff valves 
with a new actuator, having P/N 40574-4 (Model EM487-4), in 
accordance with the Accomplishment Instructions of J. C. Carter 
Company Service Bulletin 61163-28-08, dated September 1, 1994.
    (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 2: 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 December 9, 1994.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 94-30805 Filed 12-14-94; 8:45 am]
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