[Federal Register Volume 67, Number 54 (Wednesday, March 20, 2002)]
[Proposed Rules]
[Pages 12908-12910]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-6630]



[[Page 12908]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-307-AD]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model DHC-8-100, -200, and -
300 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Bombardier Model DHC-8-
100, -200, and -300 series airplanes. This proposal would require 
various modifications of the airstair (main passenger) door. This 
action is necessary to prevent failure of the airstair door to open 
after a landing, which could result in a blocked escape route during an 
emergency evacuation. This action is intended to address the identified 
unsafe condition.

DATES: Comments must be received by April 19, 2002.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-307-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: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-307-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.
    The service information referenced in the proposed rule may be 
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, 
123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This 
information 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 Parrillo, 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:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed 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 above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    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 proposed 
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 proposed 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 summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket 2000-NM-307-AD.'' The postcard will be date-stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket 2000-NM-307-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056.

Discussion

    Transport Canada Civil Aviation (TCCA), which is the airworthiness 
authority for Canada, notified the FAA that an unsafe condition may 
exist on certain Bombardier Model DHC-8-100, -200, and -300 series 
airplanes. TCCA has received numerous reports of malfunctioning 
airstair (main passenger) doors on affected airplanes. During these 
malfunctions, crewmembers had difficulty opening or closing the door, 
or were completely unable to open the door from inside or outside. The 
airstair door is a ``Type I'' exit, which is essential for evacuation 
during an emergency. Causes of a failed airstair door include a 
malfunctioning inflation valve used for the door seal, bending of the 
gas springs (gas struts), and jamming and/or breaking of the door 
balance cable. Failure of the airstair door to open after a landing, if 
not corrected, could result in a blocked escape route during an 
emergency evacuation.

Explanation of Relevant Service Information

    Bombardier has issued the service bulletins described in the 
following table:

----------------------------------------------------------------------------------------------------------------
                                          Are described in
            Procedures for--             Service Bulletin--      Revision level--               Dated--
 
----------------------------------------------------------------------------------------------------------------
Replacing the inflation valve with a               8-52-46  Original.................  September 30, 1998.
 new valve of an improved design..
Reworking the airstair door cable                  8-52-38  Original.................  October 10, 1995.
 balance assembly.                                          `A'......................  September 19, 1997.
Modifying the cable guard system by                8-52-57  Original.................  February 23, 2000.
 replacing the upper cable guards with                      `A'......................  July 28, 2000.
 new, improved cable guards.                                `B'......................  November 14, 2000.

[[Page 12909]]

 
Modifying the airstair balance system              8-52-56  `C'......................  March 10, 2000.
 by manufacturing and installing a                          `D'......................  May 18, 2000.
 support bracket assembly.                                  `E'......................  July 20, 2000.
                                                            `F'......................  August 29, 2000.
                                                            `G'......................  November 7, 2000.
Replacing the airstair door gas springs            8-52-59  Original.................  September 18, 2000.
 with new gas springs.                                      `A'......................  January 3, 2001.
----------------------------------------------------------------------------------------------------------------

    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition. TCCA 
classified Service Bulletins 8-52-46, 8-52-38, and 8-52-57 as 
mandatory; mandated accomplishment of either Service Bulletin 8-52-56 
or 8-52-59 (and allowed accomplishment of both); and issued Canadian 
airworthiness directive CF-2000-19R1, dated January 22, 2001, to ensure 
the continued airworthiness of these airplanes in Canada.

FAA's Conclusions

    These airplane models are manufactured in Canada and are 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, TCCA has kept the FAA informed of 
the situation described above. The FAA has examined the findings of 
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 Proposed 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, the proposed AD would require accomplishment of 
the actions specified in the service bulletins described previously.

Cost Impact

    The FAA provides the following cost estimates for the actions 
specified by this proposed AD:

----------------------------------------------------------------------------------------------------------------
                                                                            Number of
                                     Workhours    Labor rate   Parts cost      U.S.         Per-
    Action per Service Bulletin         per        per hour       per       airplanes     airplane    Fleet cost
                                      airplane                  airplane     affected       cost
----------------------------------------------------------------------------------------------------------------
8-52-46...........................            3          $60         $297          194         $477      $92,538
8-52-38...........................            4           60        1,930          130        2,170      282,100
8-52-57...........................            1           60            0          194           60       11,640
8-52-56...........................            4           60            0          194          240       46,560
8-52-59...........................            3           60            0          194          180       34,920
----------------------------------------------------------------------------------------------------------------

    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the proposed requirements 
of this AD action, and that no operator would accomplish those actions 
in the future if this proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up, planning time, or time 
necessitated by other administrative actions.

Regulatory Impact

    The regulations proposed herein would 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 proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, will not have a significant economic impact, 
positive or negative, on a substantial number of small entities under 
the criteria of the Regulatory Flexibility Act. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting 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.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
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:
Bombardier, Inc. (Formerly de Havilland, Inc.): Docket 2000-NM-307-
AD.
Applicability: Model DHC-8-100, -200, and -300 series airplanes; 
certificated in any category; serial numbers 003 through 550 
inclusive.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been

[[Page 12910]]

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 (b) 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 failure of the airstair door to open after a landing, 
which could result in a blocked escape route during an emergency 
evacuation, accomplish the following:

Modifications

    (a) Modify the airplane as specified by the following table:

                                        Table--Modification Requirements
----------------------------------------------------------------------------------------------------------------
                                                                                          In accordance with the
                                                                                              Accomplishment
             For Model--                 Modify the airstair            Within--             Instructions of
                                              door by--                                     Bombardier Service
                                                                                                Bulletin--
----------------------------------------------------------------------------------------------------------------
(1) DHC-8-102, -103, -106, -201, 202,  Replacing the inflation  6 months after the       8-52-46, dated
 301, -311, and -315 series             valve with a new valve   effective date of this   September 30, 1998.
 airplanes; serial numbers 003          of an improved design    AD.
 through 522 inclusive.                 (Modsum 8Q100185).
(2) DHC-8-102, -103, -106, -301, -     Reworking the airstair   6 months after the       8-52-38, dated October
 311, and -315 series airplanes;        door cable balance       effective date of this   10, 1995; or
 serial numbers 003 through 400         assembly (Modsum 8/      AD.                     8-52-38, Revision `A,'
 inclusive.                             2205).                                            dated September 19,
                                                                                          1997.
(3) DHC-8-102, -103, -106, -201, -     Replacing the upper      6 months after the       8-52-57, dated February
 202, -301, 311, and -315 series        cable guards on the      effective date of this   23, 2000; or
 airplanes; serial numbers 003          airstair door with       AD, but after the       8-52-58, Revision `A,'
 through 550 inclusive.                 new, improved cable      modification required    dated July 28, 2000;
                                        guards (Modsum           by paragraph (a)(2) of   or
                                        8Q101093).               this AD.                8-52-57, Revision `B,'
                                                                                          dated November 14,
                                                                                          2000.
(4) DHC-8-102, 103, 106, 201, 202,     (i) Manufacturing and    6 months after the       8-52-56, Revision `C,'
 301, 311, and 315 series airplanes;    installing a support     effective date of this   dated March 10, 2000;
 serial numbers 003 through 550         bracket assembly         AD.                      or
 inclusive.                             (Modsum 8Q101086); and/                          8-52-56, Revision `D,'
                                        or.                                               dated May 18, 2000; or
                                                                                         8-52-56, Revision `E,'
                                                                                          dated July 20, 2000;
                                                                                          or
                                                                                         8-52-56, Revision `F,'
                                                                                          dated August 29, 2000;
                                                                                          or
                                                                                         8-52-56, Revision `G,'
                                                                                          dated November 7,
                                                                                          2000.
                                       (ii) Replacing the       6 months after the       8-52-59; dated
                                        airstair door gas        effective date of this   September 18, 2000; or
                                        springs with new gas     AD.                     8-52-59; Revision `A,'
                                        springs (Modsum                                   dated January 3, 2001.
                                        8Q101074).
----------------------------------------------------------------------------------------------------------------


    Note 2:  Modsum 8Q101093 (paragraph (a)(3) of this AD) cannot be 
accomplished before Modification 8/2205 (paragraph (a)(2) of this 
AD), because Modsum 8Q101093 introduces a redesigned cable guard 
that replaces a cable guard that is part of Modification 8/2205.


    Note 3: Modification as specified by either paragraph (a)(4)(i) 
or (a)(4)(ii)--or both--of this AD is acceptable for compliance with 
the requirements of paragraph (a)(4) of this AD.

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 4: 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 5: The subject of this AD is addressed in Canadian 
airworthiness directive CF-2000-19R1, dated January 22, 2001.


    Issued in Renton, Washington, on March 13, 2002.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 02-6630 Filed 3-19-02; 8:45 am]
BILLING CODE 4910-13-P