[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]
BILLING CODE 4910-13-U
