[Federal Register Volume 61, Number 157 (Tuesday, August 13, 1996)]
[Rules and Regulations]
[Pages 41953-41955]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-20428]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
14 CFR Part 39
[Docket No. 96-NM-195-AD; Amendment 39-9710; AD 96-17-02]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 757 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to certain Boeing Model 757 series airplanes. This action
requires an inspection of the engine fuel shutoff valves (spar valves)
to detect leakage of fuel and to ensure that no leakage occurs when the
valves are commanded to close. This action also requires an alignment
procedure of the engine fuel shutoff valves, if necessary. This
amendment is prompted by reports that certain engine shutoff valve
assemblies were improperly installed during manufacturing of the
airplane. The actions specified in this AD are intended to prevent
uncommanded fuel flow from the fuel tanks to the engine nacelle, which
could result in reduced aircraft fire protection in the event of a leak
in the engine fuel line or a fire in the engine nacelle.
DATES: Effective August 28, 1996.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of August 28, 1996.
Comments for inclusion in the Rules Docket must be received on or
before October 15, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 96-NM-195-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056.
The service information referenced in this AD 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; or at
the Office of the Federal Register, 800 North Capitol Street, NW.,
suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Bernie Gonzalez, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton, Washington; telephone (206) 227-
2682; fax (206) 227-1181.
SUPPLEMENTARY INFORMATION: The FAA has received reports that certain
defueling valve assemblies were improperly installed on a Boeing Model
757 series airplane during manufacturing. Such improper installation
results in uncommanded transfer of fuel from tank to tank.
Investigation revealed that the engine fuel shutoff valves (spar
valves) are installed in the same manner and are identical to the
defueling valves. While leakage of the defueling valves can be readily
and immediately detected, leakage of engine fuel shutoff valves cannot
be detected unless the main engine fuel supply line is open.
Furthermore, since the engine fuel shutoff valves leak in the commanded
``closed'' position, the Engine Indication and Crew Alerting System
(EICAS) does not show an advisory message, and the amber ``SPAR VALVE''
disagreement light on the P10 fuel control switch panel does not
illuminate.
The engine fuel shutoff valve is controlled by the appropriate fuel
control switch on the P10 panel of the
[[Page 41954]]
control stand. The valve is closed when the switch is in the ``CUTOFF''
position, and is open when the switch is in the ``RICH'' (for Rolls
Royce engines only) or in the ``RUN'' position. The amber ``SPAR
VALVE'' disagreement light above each fuel control switch illuminates
anytime the valve is not in the commanded position. The EICAS advisory
message, ``L (or R) FUEL SPAR VAL'' will appear after six seconds when
disagreement exists. The valve closes when the fire handle is pulled.
The engine fuel shutoff valve provides fire protection to the
airplane by shutting off fuel at the wing in the event of a leak in the
engine fuel line or a fire in the engine nacelle. If the engine fuel
shutoff valve does not fully close when commanded, fuel may continue to
flow from the wing to the engine. This condition, if not corrected,
could result in uncommanded fuel flow from the fuel tanks to the engine
nacelle, which could result in reduced fire protection of the airplane
in the event of a leak in the engine fuel line or a fire in the engine
nacelle.
Explanation of Relevant Service Information
The FAA has reviewed and approved Boeing Alert Service Bulletin
757-28A0045, dated July 30, 1996, which describes procedures for
inspection of the engine fuel shutoff valves (spar valves) to detect
leakage of fuel and to ensure that no leakage occurs when the valves
are commanded to close. This alert service bulletin also describes
procedures for an alignment of the engine fuel shutoff valve(s) for
those airplanes that do not pass the inspection to detect leakage of
fuel.
Explanation of the Requirements of the Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other Boeing Model 757 series airplanes of the same
type design, this AD is being issued to prevent uncommanded fuel flow
from the fuel tanks to the engine nacelle, which could result in
reduced fire protection of the airplane in the event of a leak in the
engine fuel line or a fire in the engine nacelle. This AD requires
inspection of the engine fuel shutoff valves to detect leakage of fuel
and to ensure that no leakage occurs when the valves are commanded to
close. This AD also requires an alignment of the engine fuel shutoff
valve(s) for those airplanes that do not pass the inspection for
leakage. The actions are required to be accomplished in accordance with
the service bulletin described previously.
Procedure for Alignment of the Fuel Shutoff Valves
Operators should note that the alert service bulletin recommends
accomplishing the alignment procedure of the engine fuel shutoff valves
with a specific tool (part number B28009) or an alignment procedure
that entails removing the engine fuel shutoff valve motor and actuator.
The FAA has determined that accomplishment of the alignment using the
alignment tool will provide a more accurate and permanent alignment of
the engine fuel shutoff valves. However, the FAA has been advised by
the manufacturer that there is a delay in the availability of this
particular tool. Therefore, the FAA considers this AD to be interim
action, and is currently considering requiring the accomplishment of
the alignment procedure of the engine fuel shutoff valves with
alignment tool part number B28009. The planned compliance time for the
accomplishment of the alignment procedure using that alignment tool is
sufficiently long so that prior notice and time for public comment will
be practicable.
Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the 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 that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 96-NM-195-AD.'' The postcard will be date stamped and
returned to the commenter.
Regulatory Impact
The regulations adopted herein will 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 final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, may be obtained from the Rules Docket at the
location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 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:
[[Page 41955]]
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:
96-17-02 Boeing: Amendment 39-9710. Docket 96-NM-195-AD.
Applicability: Model 757 series airplanes, line positions 478
through 699 inclusive; 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 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 uncommanded fuel flow from the fuel tanks to the
engine nacelle in the event of a leak in the engine fuel line or a
fire in the engine nacelle, accomplish the following:
(a) Within 60 days after the effective date of this AD, perform
an inspection to detect leakage of the fuel shutoff (spar) valves
and verify that the valves do not leak when commanded to close, in
accordance with Boeing Alert Service Bulletin 757-28A0045, dated
July 30, 1996.
(1) If both fuel shutoff valves pass the inspection for leakage
and the valves close when commanded, no further action is required
by this AD.
(2) If either or both of the fuel shutoff valves do not pass the
inspection for leakage: Prior to further flight, adjust the engine
fuel shutoff valve(s) in accordance with Part III of the alert
service bulletin and repeat the requirements of paragraph (a) of
this AD.
(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) The actions shall be done in accordance with Boeing Alert
Service Bulletin 757-28A0045, dated July 30, 1996. This
incorporation by reference was approved by the Director of the
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part
51. Copies may be obtained from Boeing Commercial Airplane Group,
P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be
inspected at the FAA, Transport Airplane Directorate, 1601 Lind
Avenue, SW., Renton, Washington; or at the Office of the Federal
Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(d) This amendment becomes effective on August 28, 1996.
Issued in Renton, Washington, on August 6, 1996.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-20428 Filed 8-12-96; 8:45 am]
BILLING CODE 4910-13-U