AD 2000-22-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Boeing | 737 | Airworthiness Directives; Boeing Model 737 Series Airplanes |
Unsafe Condition
Failure modes in the rudder system of Boeing Model 737 series airplanes that can cause an uncommanded rudder hardover, including single jam modes and latent failures or jams that, when combined with a second failure or jam, could cause an uncommanded rudder hardover.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise the FAA-approved Airplane Flight Manual (AFM) to include a simplified procedure titled 'Uncommanded Rudder' to address a jammed or restricted flight control condition.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 30 days after January 17, 1997 (the effective date of AD 96-26-07, amendment 39-9871).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
All Boeing Model 737 series airplanes, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This amendment supersedes an existing airworthiness directive (AD), applicable to all Boeing Model 737 series airplanes, that currently requires revising the FAA-approved Airplane Flight Manual (AFM). This new amendment revises the AFM procedure in the existing AD to simplify the instructions for correcting a jammed or restricted flight control condition. This amendment is prompted by an FAA determination that the procedure currently inserted in the AFM by the existing AD is not defined adequately. The actions specified in this AD are intended to ensure that the flight crew is advised of the procedures necessary to address a condition involving a jammed or restricted rudder.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 65, Number 208 (Thursday, October 26, 2000)]
[Rules and Regulations]
[Pages 64134-64136]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 00-27508]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2000-NM-325-AD; Amendment 39-11948; AD 2000-22-02]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: This amendment supersedes an existing airworthiness directive
(AD), applicable to all Boeing Model 737 series airplanes, that
currently requires revising the FAA-approved Airplane Flight Manual
(AFM). This new amendment revises the AFM procedure in the existing AD
to simplify the instructions for correcting a jammed or restricted
flight control condition. This amendment is prompted by an FAA
determination that the procedure currently inserted in the AFM by the
existing AD is not defined adequately. The actions specified in this AD
are intended to ensure that the flight crew is advised of the
procedures necessary to address a condition involving a jammed or
restricted rudder.
DATES: Effective November 13, 2000. Comments for inclusion in the Rules
Docket must be received on or before December 26, 2000.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2000-NM-325-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9 a.m. and 3 p.m., Monday through Friday, except
Federal holidays. Comments may be submitted via fax to (425) 227-1232.
Comments may also be sent via the Internet using the following address:
<a href="/cdn-cgi/l/email-protection#21180c404f4c0c484053424e4c4c444f55614740400f464e57"><span class="__cf_email__" data-cfemail="724b5f131c1f5f1b1300111d1f1f171c06321413135c151d04">[email protected]</span></a>. Comments sent via fax or the Internet must
contain ``Docket No. 2000-NM-325-AD'' in the subject line and need not
be submitted in triplicate. Comments sent via the Internet as attached
electronic files must be formatted in Microsoft Word 97 for Windows or
ASCII text.
ADDRESSES: Information pertaining to this amendment may be examined at
the Federal Aviation Administration (FAA), Transport Airplane
Directorate, Rules Docket No. 2000-NM-325-AD, 1601 Lind Avenue, SW.,
Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Steve O'Neal, Aerospace Engineer,
Flight Test Branch, ANM-160S, Seattle Aircraft Certification Office,
FAA, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone
(425) 227-2699; fax (425) 227-1181.
SUPPLEMENTARY INFORMATION: On December 23, 1996, the FAA issued AD 96-
26-07, amendment 39-9871 (62 FR 15, January 2, 1997), applicable to all
Boeing Model 737 series airplanes, to require revising the FAA-approved
Airplane Flight Manual (AFM) to include procedures that will enable the
flight crew to take appropriate action to maintain control of the
airplane during an uncommanded yaw or roll condition, and to correct a
jammed or restricted flight control condition. That action was prompted
by an FAA determination that such procedures were not defined
adequately in the AFM for these airplanes. Because of the potential for
uncommanded yaw or roll conditions in these airplanes, and jammed or
restricted flight controls, the actions required by that AD are
intended to provide the flight crew with a systematic means to isolate
flight control hydraulics, eliminate a rudder hardover, and land
safely.
Actions Since Issuance of Previous Rule
Since the issuance of AD 96-26-07, the FAA has received information
from the Independent 737 Flight Controls Engineering and Test
Evaluation Board (ETEB) verifying several failure modes in the rudder
system of Model 737-100 and -200 (Initial); 737-300, -400, and -500
(Classic); and 737-600, -700, and -800 (Next Generation) series
airplanes that can cause an uncommanded rudder hardover. The failure
modes include several single jam modes that can cause an uncommanded
rudder hardover, in addition to several latent failures or jams that,
when combined with a second failure or jam, could cause an uncommanded
rudder hardover. Changes in maintenance procedures will be adopted to
enhance the detection of latent failure conditions, reducing the
potential for an uncommanded hardover. To eliminate these rudder
failure modes, the manufacturer is redesigning the rudder system.
The procedure required by AD 96-26-07, and revised by this AD, is
not as complete a solution to the rudder hardover concern as is the
rudder system redesign, for two reasons:
<bullet> First, the procedure is not effective throughout the
entire flight envelope, having limited effectiveness during the remote
possibility of a hardover during takeoff and landing.
<bullet> Second, as a general principal, eliminating the
possibility of an in-flight situation is a better alternative than
relying on flight crew action to correct such a situation.
The rudder system redesign is likely to eliminate the need for
procedures dealing with jammed or restricted flight control conditions,
but retrofit of the hardware on existing airplanes will take several
years to complete. During this time, procedures for jammed or
restricted flight control conditions will continue to be necessary. The
ETEB determined that the AFM procedure addressing a jammed or
restricted rudder required by AD 96-26-07 is inadequate and must be
revised. During evaluations of the existing procedure, the ETEB
determined that flight crews were confused by the procedure and were
not always able to complete it during simulated rudder system
malfunctions. Therefore, the FAA has determined that a revised
procedure titled ``Uncommanded Rudder,'' in lieu of the existing
procedure titled ``Jammed or Restricted Rudder,'' is necessary in the
interim period to ensure airplane safety.
[[Page 64135]]
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
supersedes AD 96-26-07 to require revising the AFM procedure in the
existing AD to simplify the instructions for correcting a jammed or
restricted flight control condition.
Interim Action
This is considered to be interim action. As previously stated, once
the rudder system is redesigned, and the retrofitted rudder is approved
and available, the FAA may consider additional rulemaking.
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.
Submit comments using the following format:
<bullet> Organize comments issue-by-issue. For example, discuss a
request to change the compliance time and a request to change the
service bulletin reference as two separate issues.
<bullet> For each issue, state what specific change to the AD is
being requested.
<bullet> Include justification (e.g., reasons or data) for each
request.
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 2000-NM-325-AD.'' The postcard will be date stamped
and returned to the commenter.
Regulatory Impact
The regulations adopted herein will not have a substantial direct
effect 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, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
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 39-9871 (62 FR
15, January 2, 1997), and by adding a new airworthiness directive (AD),
amendment 39-11948, to read as follows:
2000-22-02 Boeing: Amendment 39-11948. Docket 2000-NM-325-AD.
Supersedes AD 96-26-07, Amendment 39-9871.
Applicability: All Model 737 series airplanes, certificated in
any category.
Compliance: Required as indicated, unless accomplished
previously.
To ensure that the flight crew is advised of the procedures
necessary to address a condition involving a jammed or restricted
rudder, accomplish the following:
RESTATEMENT OF CERTAIN REQUIREMENTS OF AD 96-26-07:
(a) Within 30 days after January 17, 1997 (the effective date of
AD 96-26-07, amendment 39-9871): Revise the Emergency Procedures
Section of the FAA-approved Airplane Flight Manual (AFM) to include
the following recall item, which will enable the flight crew to take
appropriate action to maintain control of the airplane during an
uncommanded yaw or roll condition. This may be accomplished by
inserting a copy of this AD in the AFM.
``UNCOMMANDED YAW OR ROLL
RECALL
Maintain control of the airplane with all available flight controls.
If roll is uncontrollable, immediately reduce angle of attack and
increase airspeed. Do not attempt to maintain altitude until control
is recovered. If engaged, disconnect autopilot and autothrottle.''
NEW REQUIREMENTS OF THIS AD:
(b) Within 30 days after the effective date of this AD: Revise
the Normal Procedures Section of the FAA-approved AFM for Model 737-
100 and -200 series airplanes or the Non-Normal Procedures Section
of the FAA-approved AFM for Model 737-300, -400, -500, -600, -700,
and -800 series airplanes, as applicable, to include the following
procedure. This may be accomplished by inserting a copy of this AD
in the AFM and removing the existing copy (inserted as required by
AD 96-26-07), entitled ``Jammed Flight Controls.''
UNCOMMANDED RUDDER
Condition: Uncommanded rudder pedal displacement or pedal kicks.
AUTOPILOT (if engaged): DISENGAGE.
Maintain control of the airplane with all available flight
controls. If roll is uncontrollable, immediately reduce pitch/angle
of attack and increase airspeed. Do not attempt to maintain altitude
until control is recovered.
AUTOTHROTTLE (if engaged): DISENGAGE.
Verify thrust is symmetrical.
YAW DAMPER SWITCH: OFF.
RUDDER TRIM: CENTER.
RUDDER PEDALS: FREE & CENTER.
[[Page 64136]]
Use maximum force including a combined effort of both pilots, if
required to free and center the rudder pedals.
If rudder pedal position or movement is not normal and the
condition is not the result of rudder trim:
SYSTEM B FLIGHT CONTROL SWITCH: STBY RUD.
A slight rudder deflection may remain, but continued rudder
pedal pressure may help maintain an in-trim condition.
Sufficient directional control is available on landing using
differential braking and nose wheel steering.
Crosswind capability may be reduced.
Do not use autobrakes.
Consider checking rudder freedom of movement at a safe altitude
using slow rudder inputs while in the landing configuration and at
approach speed.
If condition was the result of rudder trim or environmental
factors:
YAW DAMPER SWITCH: ON.
Accomplish the normal DESCENT--APPROACH and LANDING
checklists.''
(c) It is acceptable to modify the format of the above procedure
to reflect the format used by individual carriers. However, the
procedural sequence, memory items, and/or associated text may not be
modified, except by submitting a request for an alternative method
of compliance (AMOC) as specified in paragraph (d) of this AD.
Alternative Methods of Compliance
(d) An AMOC 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. 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 1: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
Special Flight Permits
(e) 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.
Effective Date
(f) This amendment becomes effective on November 13, 2000.
Issued in Renton, Washington, on October 20, 2000.
John J. Hickey,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 00-27508 Filed 10-25-00; 8:45 am]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.