[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 [www.gpo.gov]
[FR Doc No: 00-27508]


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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.

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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: 
[email protected]. 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:
     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.
     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:
     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.
     For each issue, state what specific change to the AD is 
being requested.
     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