[Federal Register Volume 63, Number 219 (Friday, November 13, 1998)]
[Rules and Regulations]
[Pages 63390-63391]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-30335]
[[Page 63390]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-294-AD; Amendment 39-10887; AD 96-04-11 R1]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 757-200 Series Airplanes
Equipped With Rolls Royce Model RB211-535E4/E4B Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment revises an existing airworthiness directive
(AD), applicable to certain Boeing Model 757-200 series airplanes, that
currently requires a revision to the Airplane Flight Manual to ensure
that the flightcrew activates the engine cowl thermal anti-ice (CTAI)
system for both engines at the top of descent to avoid engine rundown
(loss of engine power). This amendment clarifies the relationship
between two existing AD's. The actions specified in this AD are
intended to ensure that the flightcrew activates the engine cowl
thermal anti-ice system for both engines prior to descent; activation
of the engine CTAI system in the middle of descent could result in a
compressor stall and subsequent engine rundown of multiple engines.
DATES: Effective November 30, 1998.
Comments for inclusion in the Rules Docket must be received on or
before January 12, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 98-NM-294-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Information pertaining to this amendment
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; telephone (425) 227-
1547; fax (425) 227-1181.
SUPPLEMENTARY INFORMATION: On February 15, 1996, the FAA issued AD 96-
04-11, amendment 39-9523 (61 FR 6935, February 23, 1996), applicable to
certain Boeing Model 757-200 series airplanes, to require a revision to
the FAA-approved Airplane Flight Manual to ensure that the flightcrew
activates the engine cowl thermal anti-ice (CTAI) system for both
engines at the top of descent to avoid engine rundown (loss of engine
power). That action was prompted by reports that, after the flightcrew
activated the engine CTAI during descent, engine rundown occurred due
to unknown reasons. The actions required by that AD are intended to
ensure that the flightcrew activates the engine CTAI system for both
engines prior to descent; activation of the engine CTAI system in the
middle of descent could result in a compressor stall and subsequent
engine rundown of multiple engines.
In the preamble to AD 96-04-11, the FAA indicated that the actions
required by that AD were considered interim action. Rolls Royce had
advised the FAA that it was developing a modification that will
positively address the identified unsafe condition.
Actions Since Issuance of Previous Rule
Since the issuance of that AD, the FAA issued AD 97-02-12,
amendment 39-9897 (62 FR 4899, February 3, 1997). That AD applies to
Rolls Royce Model RB211-535E4 and -535E4-B turbofan engines installed
on Boeing Model 757-200 series airplanes. It requires installation of
an improved fuel flow governor that incorporates revised minimum
compressor discharge P4 stop settings. That AD indicates that
installation of these improved fuel flow governors on both engines of
Model 757 series airplanes constitutes terminating action for the
requirements of AD 96-04-11.
Consequently, the FAA has determined that further rulemaking is
necessary to revise AD 96-04-11 to clarify the relationship of that AD
to AD 97-02-12 by indicating that installation of the improved fuel
flow governors (as required by AD 97-02-12) terminates the requirements
of AD 96-04-11.
Explanation of Requirements of Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of this same type design, this AD
revises AD 96-04-11 to continue to require a revision to the Airplane
Flight Manual to ensure that the flightcrew activates the engine cowl
thermal anti-ice (CTAI) system for both engines at the top of descent
to avoid engine rundown (loss of engine power). This AD merely
clarifies the relationship between AD 96-04-11 and AD 97-02-12.
Determination of Rule's Effective Date
Since this AD merely provides information regarding the effect of
another AD, and does not change the existing requirements, it is found
that notice and opportunity for prior public comment hereon are
unnecessary, 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 98-NM-294-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
[[Page 63391]]
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, 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:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-9523 (61 FR
6935, February 23, 1996), and by adding a new airworthiness directive
(AD), amendment 39-10887, to read as follows:
96-04-11 R1 Boeing: Amendment 39-10887. Docket 98-NM-294-AD.
Revises AD 96-04-11, amendment 39-9523.
Applicability: Model 757-200 series airplanes, equipped with
Rolls Royce Model RB211-535E4/E4B engines; certificated in any
category.
Compliance: Required as indicated, unless accomplished
previously.
To reduce the risk of engine rundown during idle descents,
accomplish the following:
(a) Within 30 days after March 11, 1996 (the effective date of
AD 96-04-11, amendment 39-9523), revise the Limitations Section of
the FAA-approved Airplane Flight Manual (AFM) to include the
following statement. This may be accomplished by inserting a copy of
this AD in the AFM.
``Limitations Section 1
In order to reduce the risk of engine rundown during idle
descents, activate the engine cowl thermal anti-ice system for both
engines prior to idle descents above flight level (FL) 200. Below FL
200, use normal engine cowl thermal anti-ice system procedures (as
defined in the AFM).
Note: The Master Minimum Equipment List (MMEL) for Model 757
series airplanes currently specifies that an airplane may be
dispatched with an engine anti-ice valve locked in the closed
position. The requirement of this section to activate the engine
cowl thermal anti-ice system prior to descent will prevent the
dispatch of airplanes with an engine anti-ice valve locked in the
closed or open position. Where differences exist between the current
specification of the MMEL and the requirements of this AFM
limitation, the AFM limitation prevails.''
Note 1: AD 97-02-12, amendment 39-9897, requires installation of
improved fuel flow governors (FFG) on both engines of Boeing Model
757-200 series airplanes. Accomplishment of this installation
constitutes terminating action for the requirements 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
Operations 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
Secs. 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.
(d) This amendment becomes effective on November 30, 1998.
Issued in Renton, Washington, on November 4, 1998.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-30335 Filed 11-12-98; 8:45 am]
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