AD 2001-11-10

final rule

Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes

AD Number
2001-11-10
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2001-NM-144-AD
FR Citation
66 FR 30305
Technical illustration of an aircraft landing gear and wheel assembly
Problem area Landing gear

Applicability

TypeManufacturerModelDetails
aircraft Bombardier DHC-8-400 Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes

Unsafe Condition

Failure of the downlock proximity sensors of the main landing gear (MLG) may result in the MLG failing to extend and providing misleading indications that the MLG has extended.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Revise the Normal and Abnormal Sections of the FAA-approved Airplane Flight Manual (AFM) to include procedures for determining if the main landing gear is extended before landing and taking appropriate actions if necessary.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 14 days after the effective date of this AD.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Bombardier Model DHC-8-400 series airplanes, serial numbers 4002 and subsequent, certificated in any category.

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 Bombardier Model DHC-8-400 series airplanes. This action requires revising the Normal and Abnormal Sections of the FAA-approved Airplane Flight Manual to include procedures that enable the flightcrew to determine if the main landing gear (MLG) is extended before landing and to take appropriate actions, if necessary. The actions specified in this AD are intended to ensure that the flightcrew is advised of a potential gear-up landing due to misleading indications of the MLG extension, and has the procedures necessary to address that potential condition. 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 109 (Wednesday, June 6, 2001)]
[Rules and Regulations]
[Pages 30305-30306]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 01-13995]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-144-AD; Amendment 39-12253; AD 2001-11-10]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model DHC-8-400 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 certain Bombardier Model DHC-8-400 series airplanes. 
This action requires revising the Normal and Abnormal Sections of the 
FAA-approved Airplane Flight Manual to include procedures that enable 
the flightcrew to determine if the main landing gear (MLG) is extended 
before landing and to take appropriate actions, if necessary. The 
actions specified in this AD are intended to ensure that the flightcrew 
is advised of a potential gear-up landing due to misleading indications 
of the MLG extension, and has the procedures necessary to address that 
potential condition. This action is intended to address the identified 
unsafe condition.

DATES: Effective June 21, 2001. Comments for inclusion in the Rules 
Docket must be received on or before July 6, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-144-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 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#d2ebffb3bcbfffbbb3a0b1bdbfbfb7bca692b4b3b3fcb5bda4"><span class="__cf_email__" data-cfemail="1821357976753571796a7b7775757d766c587e7979367f776e">[email&#160;protected]</span></a>. Comments sent via fax or the Internet must 
contain ``Docket No. 2001-NM-144-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 the amendment may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, New York Aircraft Certification Office, 10 
Fifth Street, Third Floor, Valley Stream, New York.

FOR FURTHER INFORMATION CONTACT: Dan Parillo, Aerospace Engineer, 
Systems and Flight Test Branch, ANE-172, FAA, New York Aircraft 
Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New 
York 11581; telephone (516) 256-7505; fax (516) 568-2716.

SUPPLEMENTARY INFORMATION: Transport Canada Civil Aviation (TCCA), 
which is the airworthiness authority for Canada, recently notified the 
FAA that an unsafe condition may exist on certain Bombardier Model DHC-
8-400 series airplanes. TCCA advises that downlock proximity sensors of 
the main landing gear (MLG) may fail concurrently on the same gear. 
Such failure of the sensors could result in the failure of the MLG to 
extend and the flightcrew to receive misleading indications that the 
MLG has extended.

Issuance of a Canadian Airworthiness Directive

    TCCA has issued Canadian airworthiness directive CF-2001-16, dated 
April 11, 2001, that describes an additional in-flight procedure to the 
airplane flight manual (AFM). The in-flight procedure describes certain 
cautions and warnings for performing an alternate landing gear 
extension; visually inspecting the MLG to confirm that it has been 
extended; inserting a hydraulic pump handle in socket and operating for 
a minimum of 12 full strokes and ensuring resistance to pump handle 
movement; and observing that the LEFT gear safe (green) and RIGHT gear 
safe (green) advisory lights are illuminated; and the LEFT gear unsafe 
(red) and RIGHT gear unsafe (red) and the landing handle (amber) 
advisory lights are extinguished. TCCA has issued the Canadian 
airworthiness directive in order to assure the continued airworthiness 
of these airplanes in Canada.

FAA's Conclusions

    This airplane model is manufactured in and is type certificated for 
operation in the United States under the provisions of section 21.29 of 
the Federal Aviation Regulations (14 CFR 21.29) and the applicable 
bilateral airworthiness agreement. Pursuant to this bilateral 
airworthiness agreement, has kept the FAA informed of the situation 
described above. The FAA has examined the findings of the TCCA, 
reviewed all available information, and determined that AD action is 
necessary for products of this type design that are certificated for 
operation in the United States.

Explanation of Requirements of Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, this AD is being issued to ensure that the 
flightcrew is advised of the potential of a landing with the MLG up due 
to misleading indications of the extension of the MLG, and has the 
appropriate AFM procedures necessary to address it. This AD requires a 
revision of the Normal and Abnormal Sections of the FAA-approved AFM as 
specified in the Canadian airworthiness directive described previously.

Interim Action

    This is considered to be interim action until final action is 
identified, at which time the FAA may consider further 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

[[Page 30306]]

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 2001-NM-144-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:

2001-11-10  Bombardier, Inc.: Amendment 39-12253. Docket 2001-NM-
144-AD.

Applicability: Model DHC-8-400 series airplanes, serial numbers 4002 
and subsequent, certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent landing with the main landing gear (MLG) up due to 
failure of the downlock proximity sensors of the MLG, accomplish the 
following:

Airplane Flight Manual (AFM) Revision

    (a) Within 14 days after the effective date of this AD, revise 
the Normal and Abnormal Sections of the FAA-approved AFM by 
inserting the following into Section 4.21, opposite page 4.21.1. 
This may be accomplished by inserting a copy of this AD in the AFM.

``CAUTION

    If illumination of LEFT gear safe (green), and LEFT gear unsafe 
(red), and landing gear handle (amber) advisory lights with the 
landing gear handle in the up position.

    Or
    Illumination of RIGHT gear safe (green), and RIGHT gear unsafe 
(red), and landing gear handle (amber) advisory lights with the 
landing gear handle in the up position.
    1. Perform an Alternate Landing Gear extension, See paragraph 
4.21.

WARNING

    Selection of the gear down without following the Alternate 
Landing Gear Extension procedure may result in the affected gear 
being trapped inside the nacelle.
    2. Visually inspect Main Landing Gear to confirm that it has 
been extended.

WARNING

    A down and locked indication of the affected main landing gear 
is not a valid indication of the gear position.
    3. Insert hydraulic pump handle in socket and operate for a 
minimum of 12 full strokes and ensure resistance to pump handle 
movement.
    4. Observe the LEFT gear safe (green) and RIGHT gear safe 
(green) advisory lights are illuminated and the LEFT gear unsafe 
(red) and RIGHT gear unsafe (red) and the landing handle (amber) 
advisory lights are extinguished.''

Alternative Methods of Compliance

    (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, New York 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, New York ACO.

    Note 1: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York ACO.

Special Flight Permits

    (c) 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.

    Note 2: The subject of this AD is addressed in Canadian 
airworthiness directive CF-2001-16, dated April 11, 2001.

    (d) This amendment becomes effective on June 21, 2001.


    Issued in Renton, Washington, on May 25, 2001.
Vi L. Lipski,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-13995 Filed 6-5-01; 8:45 am]
BILLING CODE 4910-13-U

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Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

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