AD 2001-07-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | McDonnell Douglas | DC-9-81 | Airworthiness Directives; McDonnell Douglas Model DC-9-81, -82, -83, and -87 Series Airplanes, Model MD-88 Airplanes, and Model MD-90-30 Series Airplanes |
Unsafe Condition
Failure of the weight-on-wheels spoiler lockout mechanism system and possible inactivation of the autospoiler actuator, which could result in the airplane overrunning the end of the runway during landing on a wet or icy runway.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise the Performance Section of the applicable FAA-approved Airplane Flight Manual (AFM) to provide the flightcrew with the appropriate landing distance and flap positions, if applicable, for wet or icy runways. Optionally, install spoiler support bracket assemblies and relays, and revise the spoiler lockout relay wiring per applicable service bulletins.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 12 months of the effective date (April 27, 2001).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
McDonnell Douglas Model DC-9-81, -82, -83, and -87 series airplanes, Model MD-88 airplanes, and Model MD-90-30 series airplanes.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This amendment adopts a new airworthiness directive (AD) that is applicable to certain McDonnell Douglas Model DC-9-81, -82, -83, and -87 series airplanes, Model MD-88 airplanes, and Model MD-90-30 series airplanes. This action requires a revision to the applicable Airplane Flight Manual (AFM) to provide the flightcrew with the appropriate landing distance and flap positions, if applicable, for wet or icy runways. This AD also provides for an optional terminating action for the applicable AFM revision. This action is necessary to prevent the flightcrew from performing a scheduled landing on a runway of potentially insufficient length due to failure of the weight-on-wheels spoiler lockout mechanism system and possible inactivation of the autospoiler actuator, which could result in the airplane overrunning the end of the runway during landing on a wet or icy runway. This action is intended to address the identified unsafe condition.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 66, Number 71 (Thursday, April 12, 2001)]
[Rules and Regulations]
[Pages 18870-18873]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-9019]
[[Page 18870]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-NM-44-AD; Amendment 39-12176; AD 2001-07-10]
RIN 2120-AA64
Airworthiness Directives; McDonnell Douglas Model DC-9-81, -82, -
83, and -87 Series Airplanes, Model MD-88 Airplanes, and Model MD-90-30
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to certain McDonnell Douglas Model DC-9-81, -82, -83, and
-87 series airplanes, Model MD-88 airplanes, and Model MD-90-30 series
airplanes. This action requires a revision to the applicable Airplane
Flight Manual (AFM) to provide the flightcrew with the appropriate
landing distance and flap positions, if applicable, for wet or icy
runways. This AD also provides for an optional terminating action for
the applicable AFM revision. This action is necessary to prevent the
flightcrew from performing a scheduled landing on a runway of
potentially insufficient length due to failure of the weight-on-wheels
spoiler lockout mechanism system and possible inactivation of the
autospoiler actuator, which could result in the airplane overrunning
the end of the runway during landing on a wet or icy runway. This
action is intended to address the identified unsafe condition.
DATES: Effective April 27, 2001.
Comments for inclusion in the Rules Docket must be received on or
before June 11, 2001.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2001-NM-44-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#f3cade929d9ede9a9281909c9e9e969d87b3959292dd949c85"><span class="__cf_email__" data-cfemail="f9c0d4989794d490988b9a9694949c978db99f9898d79e968f">[email protected]</span></a>. Comments sent via fax or the Internet must
contain ``Docket No. 2001-NM-44-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.
Information pertaining to this amendment may be examined at the
FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,
Washington; or at the FAA, Los Angeles Aircraft Certification Office,
3960 Paramount Boulevard, Lakewood, California.
FOR FURTHER INFORMATION CONTACT: Albert Lam, Aerospace Engineer,
Systems and Equipment Branch, ANM-130L, FAA, Los Angeles Aircraft
Certification Office, 3960 Paramount Boulevard, Lakewood, California
90712-4137; telephone (562) 627-5346; fax (562) 627-5210.
SUPPLEMENTARY INFORMATION:
Background
The in-flight spoiler lockout mechanism system, which prevents
manual movement of the spoiler lever in flight, either intentionally or
unintentionally, when the flaps are extended eight degrees or greater,
installed on McDonnell Douglas Model MD-90-30 series airplanes is part
of the certification basis (i.e., 14 Code of Federal Regulations (CFR)
part 25.697(b), amendment 25-57) for those airplanes. McDonnell Douglas
Model DC-9-81, -82, -83, and -87 series airplanes, and Model MD-88
airplanes were NOT certificated with an in-flight spoiler lockout
mechanism system. However, after certification, Boeing installed a
similar system on some Model DC-9-81, -82, -83, and -87 series
airplanes, and Model MD-88 airplanes as a safety enhancement feature.
One of three events must occur during the landing phase to unlock
the spoiler lever and permit its aft movement to deploy the ground
spoilers at touchdown. The in-flight spoiler lockout mechanism system
must receive an unlocking input from the autospoiler actuator, weight-
on wheels spoiler lockout mechanism system, or nose gear ground sensing
mechanism.
Identification of Unsafe Condition
The FAA has received several reports indicating that the wiring of
the weight-on-wheels spoiler lockout mechanism system provides
insufficient current/voltage to provide full operational capability of
deployment of the ground spoilers (inboard and outboard) during ground
operation on certain McDonnell Douglas Model DC-9-81, -82, -83, and -87
series airplanes, and Model MD-88 airplanes. Investigation revealed
that such insufficient current/voltage may either cause the weight-on-
wheels spoiler lockout mechanism system to fail to actuate when
energized at main landing gear (MLG) touchdown on a wet or icy runway,
or the associated circuit breaker to trip.
On a wet or icy runway, it is also likely that MLG wheel spin-up
will be insufficient to activate the autospoiler actuator upon landing,
which initiates the procedures for unlocking the in-flight spoiler
lockout mechanism system.
The unlocking inputs of both the weight-on-wheels spoiler lockout
mechanism system and autospoiler actuator are independent of each
others input, but the in-flight spoiler lockout mechanism system will
react to whichever input occurs first. If the weight-on-wheels spoiler
lockout mechanism system fails at MLG touchdown on a wet or icy runway,
and the autospoiler actuator does not activate due to insufficient MLG
wheel spin-up, compression of the nose landing gear strut will provide
an alternate unlocking input to the in-flight spoiler lockout mechanism
system. However, if the flight crew is unaware of this failure and
inactivation on a wet or icy runway, a scheduled landing on a runway of
potentially insufficient length could occur, which could result in the
airplane overrunning the end of the runway.
The weight-on-wheels spoiler lockout mechanism system on McDonnell
Douglas Model MD-90-30 series airplanes is similar in design to that on
the affected McDonnell Douglas Model DC-9-81, -82, -83, and -87 series
airplanes, and Model MD-88 airplanes. Therefore, all of these models
may be subject to the same unsafe condition.
FAA's Determination
In light of this information, the FAA finds that, in the interim
until the terminating action (described below) can be done, certain
procedures should be included in the Performance Section of the FAA-
approved Airplane Flight Manual (AFM) of the affected airplanes to
provide the flightcrew with the appropriate landing distance and flap
positions, if applicable, for wet or icy runways.
Currently, the MD-90 and MD-80 Master Minimum Equipment List (MMEL)
allows the in-flight spoiler lockout mechanism system to be inoperative
and deactivated for 10 days, which provides unrestricted deployment of
the ground spoilers in any flight and landing phase and relief from the
landing distance penalties for wet or icy runways. However, the current
MD-90 MMEL conflicts with the
[[Page 18871]]
certification basis of McDonnell Douglas Model MD-90-30 series
airplanes, which requires the in-flight spoiler lockout mechanism
system to be installed and operative during all operations of the
airplane. The FAA finds that this system may be inoperative for 10 days
per the MMEL, but it may NOT be deactivated, as currently indicated in
the MMEL. Therefore, we have determined that, for affected McDonnell
Douglas Model MD-90-30 series airplanes, the Performance Section of the
FAA-approved AFM must be revised to include a note to alert the
flightcrew of the differences between the MMEL and this prevailing AD.
Although certain affected McDonnell Douglas Model DC-9-81, -82, -
83, and -87 series airplanes, and Model MD-88 airplanes have an in-
flight spoiler lockout mechanism system installed as a safety
enhancement feature, the system may be deactivated for 10 days per the
MMEL, because this system is NOT part of the original certification
basis of the airplane. Thus, no landing distance penalty for wet or icy
runways, as described above, is necessary when this system is
deactivated on these airplanes.
Explanation of Relevant Service Information
The FAA has reviewed and approved the applicable Boeing service
bulletins identified in the table below, which describe procedures for
installing spoiler support bracket assemblies and relays, and revising
the spoiler lockout relay wiring.
----------------------------------------------------------------------------------------------------------------
Alert service bulletin Revision level Date Model
----------------------------------------------------------------------------------------------------------------
MD80-27A359........................ Original.............. January 29, 2001...... DC-9-81, -82, -83, and -87
series airplanes, and MD-
88 airplanes.
MD80-27A359........................ 01.................... March 26, 2001........ DC-9-81, -82, -83, and -87
series airplanes, and MD-
88 airplanes.
MD90-27A031........................ Original.............. January 29, 2001...... MD-90-30 series airplanes.
MD90-27A031........................ 01.................... March 26, 2001........ MD-90-30 series airplanes.
----------------------------------------------------------------------------------------------------------------
Accomplishment of these actions eliminates the need for the
required AFM revisions described below.
Explanation of the Requirements of the Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other McDonnell Douglas Model DC-9-81, -82, -83,
and -87 series airplanes, Model MD-88 airplanes, and Model MD-90-30
series airplanes of the same type design, this AD is being issued to
prevent the flightcrew from performing a scheduled landing on a runway
of potentially insufficient length due to failure of the weight-on-
wheels spoiler lockout mechanism system and possible inactivation of
the autospoiler actuator, which could result in the airplane
overrunning the end of the runway during landing on a wet or icy
runway. This AD requires a revision to the Performance Section of the
applicable FAA-approved AFM to provide the flightcrew with the
appropriate landing distance and flap positions, if applicable, for wet
or icy runways. This AD also includes an optional terminating action
(i.e., installing spoiler support bracket assemblies and relays, and
revising the spoiler lockout relay wiring) for the applicable AFM
revision. The optional terminating action, if accomplished, is required
to be accomplished per the applicable service bulletin described
previously.
Interim Action
The FAA is considering further rulemaking action to require
accomplishment of the optional terminating action on McDonnell Douglas
Model MD-90-30 series airplanes. However, the planned compliance time
for the terminating action is sufficiently long so that prior notice
and time for public comment will be practicable.
Operators should note that the FAA does not plan on requiring
accomplishment of the optional terminating action on McDonnell Douglas
Model DC-9-81, -82, -83, and -87 series airplanes, and Model MD-88
airplanes. As discussed previously, installation of in-flight spoiler
lockout mechanism system on these airplanes is a safety enhancement
system and is not part of the certification basis of the airplane.
However, we recommend that affected operators incorporate the optional
terminating action (reference Boeing Alert Service Bulletin MD80-
27A359, dated January 29, 2001, or Revision 01, dated March 26, 2001)
instead of permanently deactivating the in-flight spoiler lockout
mechanism system.
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.
[[Page 18872]]
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 2001-NM-44-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 adding the following new
airworthiness directive:
2001-07-10 McDonnell Douglas: Amendment 39-12176. Docket 2001-NM-
44-AD.
Applicability: Models identified in Table 1 of this AD,
certificated in any category; excluding those airplanes on which the
modification specified in the applicable service bulletin listed in
Table 1 of this AD has been done. Table 1 is as follows:
Table 1.--Applicability
------------------------------------------------------------------------
Model As listed in
------------------------------------------------------------------------
DC-9-81, -83, and -87 series airplanes, Boeing Alert Service Bulletin
and MD-88 airplanes. MD80-27A359, Revision 01,
dated March 26, 2001.
MD-90-30 series airplanes.............. Boeing Alert Service Bulletin
MD90-27A031, Revision 01,
dated March 26, 2001.
------------------------------------------------------------------------
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
otherwise 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 (d) 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 the flightcrew from performing a scheduled landing on
a runway of potentially insufficient length due to failure of the
weight-on-wheels spoiler lockout mechanism system and possible
inactivation of the autospoiler actuator, which could result in the
airplane overrunning the end of the runway during landing on a wet
or icy runway, accomplish the following:
Airplane Flight Manual Revisions
(a) For Model DC-9-81, -82, -83, and -87 series airplanes, and
MD-88 airplanes: Within 48 clock hours after the effective date of
this AD, revise the Performance Section of the FAA-approved Airplane
Flight Manual (AFM) to include the following statement. This may be
done by inserting a copy of this AD in the AFM.
``In-flight Spoiler Lockout Mechanism Installed and Activated,
and Automatic Ground Spoiler System Operated.
When the in-flight spoiler lockout mechanism is installed and
activated, the wet or icy runway landing field length, which is
determined from the appropriate Landing Field Length and Speed
Chart, must be increased by 1,720 feet under either of the following
conditions:
a. The weight-on-wheels unlocking feature is not installed; or
b. The weight-on-wheels unlocking feature is installed, but
inoperative.
When the in-flight spoiler lockout mechanism is deactivated, the
above landing field length is not required.''
(b) For Model MD-90-30 series airplanes: Within 48 clock hours
after the effective date of this AD, revise the Performance Section
of the FAA-approved AFM to include the following statement. This may
be done by inserting a copy of this AD in the AFM.
``Landing Field Length for A Wet or Icy Runway.
Increase landing field length, which is determined from the
Basic Manual, by 1,800 feet (549 meters) for a wet or icy runway
with 28-degree and 40-degree flaps.
There is no landing field length penalty for a dry runway.
In-flight spoiler lockout mechanism may NOT be deactivated, as
indicated in the Master Minimum Equipment List (MMEL).''
Note 2: The MD-90 MMEL, system and sequence number 65-02, and
the second proviso of system and sequence number 65-03, specifies
currently that, for 10 days, the in-flight spoiler lockout mechanism
system may be deactivated. Where differences exist between the
current specification of the MMEL and the requirements of this AFM
limitation, the AFM limitation prevails.
Optional Terminating Modifications
(c) Accomplishment of the actions specified in paragraphs (c)(1)
and (c)(2) of this AD, per the applicable Boeing service bulletin
identified in Table 2 of this AD, constitutes terminating action for
the AFM revision requirements of paragraph (a) or (b) of this AD, as
applicable. After doing those actions, the AFM revision required by
paragraph (a) or (b) of this AD, as applicable, may be removed from
the AFM. Table 2 is as follows:
[[Page 18873]]
Table 2.--Applicable Service Bulletins
----------------------------------------------------------------------------------------------------------------
Alert service bulletin Revision level Date Model
----------------------------------------------------------------------------------------------------------------
MD80-27A359........................ Original or 01........ January 29, 2001, DC-9-81, -82, -83, and -87
March 26, 2001. series airplanes, and MD-
88 airplanes.
MD90-27A031........................ Original or 01........ January 29, 2001, MD-90-30 series airplanes.
March 26, 2001.
----------------------------------------------------------------------------------------------------------------
(1) Install the spoiler support bracket assemblies and relays;
and
(2) Revise the spoiler lockout relay wiring.
Alternative Methods of Compliance
(d) 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, Los Angeles Aircraft Certification
Office (ACO), FAA. Operators shall submit their requests through an
appropriate FAA Principal Maintenance Inspector, who may add
comments and then send it to the Manager, Los Angeles ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Los Angeles 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 April 27, 2001.
Issued in Renton, Washington, on April 5, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 01-9019 Filed 4-11-01; 8:45 am]
BILLING CODE 4910-13-U
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Retrieved: Apr 6, 2026
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