[Federal Register Volume 59, Number 80 (Tuesday, April 26, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-9989]
[[Page Unknown]]
[Federal Register: April 26, 1994]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 94-NM-50-AD; Amendment 39-8899; AD 94-09-10]
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 all Boeing Model 757 series airplanes. This action
requires revising the Non-Normal Procedures Section of the FAA-approved
Airplane Flight Manual (AFM) to include procedures that will enable the
flight crew to identify fuel system leaks and to take appropriate
action to prevent further fuel loss. This amendment is prompted by
reports that flight crew procedures related to fuel system leaks are
not defined adequately in the FAA-approved AFM for these airplanes. The
actions specified in this AD are intended to ensure that the flight
crew is advised of the potential hazard related to fuel exhaustion due
to undetected leakage, and the procedures necessary to address it.
DATES: Effective May 11, 1994.
Comments for inclusion in the Rules Docket must be received on or
before June 27, 1994.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-50-AD, 1601 Lind Avenue SW., Renton,
Washington 98055-4056.
FOR FURTHER INFORMATION CONTACT: Tamra J. Elkins, Aerospace Engineer,
Propulsion Branch, ANM-140S, FAA, Transport Airplane Directorate,
Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton,
Washington 98055-4056; telephone (206) 227-2669; fax (206) 227-1181.
SUPPLEMENTARY INFORMATION: Several in-service incidents have occurred
on Model 757 series airplanes in which an engine fuel line has
fractured and a significant fuel leak has occurred. These fuel leaks
have occurred at locations within the engine fuel system upstream of
the fuel flow transmitter. Under these circumstances, sufficient fuel
may still be supplied to the engine, and the engine may operate
normally. In these instances, the flight crew would receive no
indication of abnormal fuel flow (i.e., fuel leakage) from the fuel
flow meter. If the flight crew fails to detect a fuel leak, appropriate
action would not be taken to prevent further fuel loss. This condition,
if not corrected, could result in fuel exhaustion due to undetected
fuel leakage.
In light of this information, the FAA finds that certain procedures
should be included in the FAA-approved Airplane Flight Manual (AFM) for
Model 757 series airplanes to enable the flight crew to detect fuel
system leaks and to take appropriate action. The FAA has determined
that such procedures currently are not defined adequately in the AFM
for these airplanes.
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 ensure that flight crews are
advised of the potential hazard related to a significantly reduced or
exhausted airplane fuel supply, and of the procedures to address it.
This AD requires revising the Non-Normal Procedures Section of the AFM
to include procedures that will enable the flight crew to identify fuel
system leaks and to take appropriate action to prevent further fuel
loss.
This is considered to be interim action until final action is
identified, at which time the FAA may consider further rulemaking.
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 notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 94-NM-50-AD.'' The postcard will be date stamped and
returned to the commenter.
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 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, Safety.
Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration amends 14 CFR part
39 of the Federal Aviation Regulations 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:
94-09-10 Boeing: Amendment 39-8899. Docket 94-NM-50-AD.
Applicability: All Model 757 airplanes, certificated in any
category.
Compliance: Required as indicated, unless accomplished
previously.
To ensure that the flight crew is advised of the potential
hazard associated with fuel exhaustion due to undetected fuel
leakage, and of the procedures necessary to address it, accomplish
the following:
(a) Within 60 days after the effective date of this AD, revise
the Non-Normal Procedures Section of the FAA-approved Airplane
Flight Manual (AFM) to include the following procedures, which will
enable the flight crew to identify fuel system leaks and to take
appropriate action to prevent further fuel loss. This may be
accomplished by inserting a copy of this AD in the AFM.
``Flight Management Computer (FMC) Message Fuel QTY Error or Fuel
Disagree
Compare the Fuel Quantity Indicating System (FQIS) total fuel
quantity and the FMC calculated fuel remaining (based on fuel flow)
with estimated fuel usage data.
If a fuel leak is suspected, close the crossfeed valve and turn
off the center fuel pumps. Watch for any unusual decrease in fuel
tank quantity and/or a fuel imbalance to determine if fuel is being
lost.
If an engine fuel leak is confirmed (either visually or by
cockpit indications), shut down the affected engine to stop the leak
and retain fuel. After shutdown, fuel from the remaining center,
left, and right main tanks may be used for the operating engine. Use
FQIS to determine fuel remaining.''
(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
Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the
airplane to a location where the requirements of this AD can be
accomplished.
(d) This amendment becomes effective on May 11, 1994.
Issued in Renton, Washington, on April 20, 1994.
S. R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-9989 Filed 4-25-94; 8:45 am]
BILLING CODE 4910-13-U