[Federal Register Volume 71, Number 186 (Tuesday, September 26, 2006)]
[Proposed Rules]
[Pages 56070-56072]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 06-8233]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25904; Directorate Identifier 2006-NM-077-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) that applies to certain Bombardier Model DHC-8-100, -
200, and -300 series airplanes. The existing AD currently requires 
modification of the flight compartment door; repetitive inspections for 
wear of the flight compartment door hinges following modification; and 
repair or replacement of the hinges with new hinges if necessary. This 
proposed AD would require using revised procedures for modifying and 
inspecting the flight compartment door and would reduce the 
applicability of the existing AD. This proposed AD results from a 
determination that certain cockpit doors are no longer subject to the 
existing requirements. We are proposing this AD to prevent failure of 
the alternate release mechanism of the flight compartment door, which 
could delay or impede the evacuation of the flightcrew during an 
emergency. This failure also could result in the flightcrew not being 
able to assist passengers in the event of an emergency.

DATES: We must receive comments on this proposed AD by October 26, 
2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Bombardier, Inc., Bombardier Regional Aircraft Division, 
123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada, for service 
information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Ezra Sasson, Aerospace Engineer, 
Systems and Flight Test Branch, ANE-172, FAA, New York Aircraft 
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New 
York 11590; telephone (516) 228-7320; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``Docket No. 
FAA-2006-25904; Directorate Identifier 2006-NM-077-AD'' at the 
beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of the 
proposed AD. We will consider all comments received by the closing date 
and may amend the proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the Docket Management System 
receives them.

Discussion

    On March 30, 1999, we issued AD 99-08-04, amendment 39-11109 (64 FR 
16803, April 7, 1999), for certain Bombardier Model DHC-8-100, -200, 
and -300 series airplanes. That AD requires modification of the flight 
compartment door; repetitive inspections for wear of the flight 
compartment door hinges following modification; and repair or 
replacement of the hinges with new hinges, if necessary. That AD 
resulted from a report that the door lock mechanism of the flight 
compartment door jammed and could not be opened using the alternate 
release mechanism. We issued that AD to prevent failure of the 
alternate release mechanism of the flight compartment door, which could 
delay or impede the evacuation of the flightcrew during an emergency. 
This failure also could result in the flightcrew not being able to 
assist passengers in the event of an emergency.

Actions Since Existing AD Was Issued

    Since we issued AD 99-08-04, various civil aviation authorities 
have mandated the installation of reinforced flight compartment doors, 
which negates the need for the modification required by paragraph (a) 
of the existing AD (Modification 8/2337) for airplanes on which the 
doors were installed in production. Modifications 8/2228, 8/2229, 8/
2231, 8/2232, 8Q100859, 8Q900267, 8Q420101, 8Q420143, 8Q200131, or 
8Q420440 are equivalent to Modification 8/2337 (specified in paragraph 
(a) of the existing AD) for the flight compartment door alternate 
release mechanism. In addition, Bombardier has issued revised 
procedures for modifying and inspecting the flight compartment door.

Relevant Service Information

    Bombardier has issued Service Bulletin 8-52-39, Revision ``H,'' 
dated September 9, 2004. Revision ``H'' is similar to Revision ``D,'' 
dated February 27, 1998, which was cited in the existing AD as the 
appropriate source of service information for accomplishing the 
required actions. Among other things, Revision ``H'' revises the 
procedures used for modifying and inspecting the flight compartment 
door,

[[Page 56071]]

as specified in the original issue of Bombardier Service Bulletin 8-52-
39, dated October 31, 1996, and Revision ``A,'' of the service 
bulletin. In addition, the effectivity specified in Revision ``H'' 
excludes airplanes on which new, improved flight compartment doors have 
been installed in production.
    Transport Canada Civil Aviation (TCCA), which is the airworthiness 
authority for Canada, mandated the service information and issued 
Canadian airworthiness directive CF-1996-20R4, dated August 10, 2005, 
to ensure the continued airworthiness of these airplanes in Canada.

FAA's Determination and Requirements of the Proposed AD

    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. We have examined TCCA's findings, 
evaluated all pertinent information, and determined that AD action is 
necessary for airplanes of this type design that are certificated for 
operation in the United States.
    This proposed AD would supersede AD 99-08-04 and would retain the 
requirements of the existing AD, but would require using revised 
procedures. This proposed AD would also reduce the applicability of the 
existing AD.
    Operators should note that Note 2 of AD 99-08-04 provides credit 
for modification of the flight compartment door in accordance with 
Bombardier Service Bulletin S.B. 8-52-39, dated August 30, 1996; 
Revision ``A,'' dated October 31, 1996; Revision ``B,'' dated July 4, 
1997; or Revision ``C,'' dated September 1, 1997; if the modification 
is done before the effective date of AD 99-08-04. However, we have 
determined that the modification and inspection procedures specified in 
the original issue and Revision ``A,'' of the service bulletin are not 
adequate due to a design deficiency detected after issuance of those 
service bulletins. TCCA agrees with this finding.
    Accordingly, we have re-identified Note 2 of the existing AD as 
paragraph (i) of this proposed AD for formatting reasons. In addition, 
we have revised the content of the new paragraph (i) to remove 
references to the original issue and Revision ``A'' of the service 
bulletin, and to provide credit for accomplishing the actions in 
Revision ``E,'' dated May 10, 1999; Revision ``F,'' dated February 4, 
2000; or Revision G, dated May 17, 2001.

Clarification of Alternative Method of Compliance (AMOC) Paragraph

    We have revised this action to clarify the appropriate procedure 
for notifying the principal inspector before using any approved AMOC on 
any airplane to which the AMOC applies.

Change to Existing AD

    This proposed AD would retain the requirements of AD 99-08-04. 
Since AD 99-08-04 was issued, the AD format has been revised, and 
certain paragraphs have been rearranged. As a result, the corresponding 
paragraph identifiers have changed in this proposed AD, as listed in 
the following table:

                      Revised Paragraph Identifiers
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                                             Corresponding  requirement
        Requirement in AD 99-08-04              in this  proposed AD
------------------------------------------------------------------------
paragraph (a).............................  paragraph (f).
paragraph (b).............................  paragraph (h).
paragraph (c).............................  paragraph (j).
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Costs of Compliance

    This proposed AD would affect about 167 airplanes of U.S. registry. 
The new actions of this proposed AD add no additional economic burden. 
The current costs for this AD are repeated for the convenience of 
affected operators, as follows:
    The modification takes about 4 work hours per airplane, at an 
average labor rate of $80 per work hour. The manufacturer states that 
it will supply required parts to the operators at no cost. Based on 
these figures, the estimated cost of the modification is $53,440, or 
$320 per airplane.
    The inspection takes about 2 work hours per airplane, at an average 
labor rate of $80 per work hour. Based on these figures, the estimated 
cost of the inspection is $26,720, or $160 per airplane, per inspection 
cycle.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The Federal Aviation Administration (FAA) amends Sec.  39.13 by 
removing amendment 39-11109 (64 FR 16803, April 7, 1999) and adding the 
following new airworthiness directive (AD):

Bombardier, Inc. (Formerly de Havilland, Inc.): Docket No. FAA-2006-
25904; Directorate Identifier 2006-NM-077-AD.

[[Page 56072]]

Comments Due Date

    (a) The FAA must receive comments on this AD action by October 
26, 2006.

Affected ADs

    (b) This AD supersedes AD 99-08-04.

Applicability

    (c) This AD applies to Bombardier Model DHC-8-100, -200 and -300 
series airplanes, certificated in any category; equipped with a 
flight compartment door installation having part number (P/N) 
82510074-(*), 82510294-(*), 82510310-001, 8Z4597-001, H85250010-(*), 
82510700-(*), or 82510704-(*); except P/Ns 82510704-502 and 
82510704-503.

    Note 1: (*) denotes all dash numbers.

Unsafe Condition

    (d) This AD results from a determination that certain cockpit 
doors are no longer subject to the existing requirements. We are 
issuing this AD to prevent failure of the alternate release 
mechanism of the flight compartment door, which could delay or 
impede the evacuation of the flightcrew during an emergency. This 
failure also could result in the flightcrew not being able to assist 
passengers in the event of an emergency.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Modification

    (f) Except as required by paragraph (g) of this AD: Within 90 
days after May 12, 1999 (the effective date of AD 99-08-04), modify 
the lower hinge assembly and main door latch (Modification 8/2337) 
of the flight compartment door, in accordance with Bombardier 
Service Bulletin S.B. 8-52-39, Revision ``D,'' dated February 27, 
1998; or Revision ``H,'' dated September 9, 2004. After the 
effective date of this AD, only Revision ``H'' may be used for 
accomplishing the modification.
    (g) For airplanes on which the modification required by 
paragraph (f) of this AD was done before the effective date of this 
AD in accordance with Bombardier Service Bulletin S.B. 8-52-39, 
dated August 30, 1996; or Revision ``A,'' dated October 31, 1996: 
Within 90 days after the effective date of this AD, do the 
modification required by paragraph (f) of this AD in accordance with 
Bombardier Service Bulletin 8-52-39, Revision ``H,'' dated September 
9, 2004.

Inspection

    (h) Within 800 flight hours after doing the modification 
required by paragraph (g) of this AD: Inspect the hinge areas around 
the hinge pin holes of the flight compartment door for wear in 
accordance with Bombardier Service Bulletin S.B. 8-52-39, Revision 
``D,'' dated February 27, 1998; or Revision ``H,'' dated September 
9, 2004. After the effective date of this AD, only Revision ``H'' 
may be used for accomplishing the inspection.
    (1) If no wear is detected, or if the wear is less than or equal 
to 0.020 inch in depth, repeat the inspection thereafter at 
intervals not to exceed 800 flight hours.
    (2) If any wear is detected and its dimension around the hinge 
pin holes is less than 0.050 inch and greater than 0.020 inch in 
depth, prior to further flight, perform the applicable corrective 
actions specified in the service bulletin. Repeat the inspection 
thereafter at intervals not to exceed 800 flight hours.
    (3) If any wear is detected and its dimension around the hinge 
pin holes is greater than or equal to 0.050 inch in depth, prior to 
further flight, replace the worn hinges with new hinges in 
accordance with the service bulletin. Repeat the inspection 
thereafter at intervals not to exceed 800 flight hours.

Credit for Actions Accomplished Previously

    (i) Modifications and inspections done before the effective date 
of this AD in accordance with Bombardier Service Bulletin S.B. 8-52-
39, Revision ``B,'' dated July 4, 1997; Revision ``C,'' dated 
September 1, 1997; Revision ``E,'' dated May 10, 1999; Revision 
``F,'' dated February 4, 2000; or Revision G, dated May 17, 2001; 
are considered acceptable for compliance with the modification and 
inspections required by this AD.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, New York Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) AMOCs approved previously in accordance with AD 99-08-04 are 
approved as AMOCs for the corresponding provisions of paragraphs 
(f), (g), (h), and (i) of this AD.
    (3) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Related Information

    (k) Canadian airworthiness directive CF-1996-20R4, dated August 
10, 2005, also addresses the subject of this AD.


    Issued in Renton, Washington, on September 15, 2006.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 06-8233 Filed 9-25-06; 8:45 am]
BILLING CODE 4910-13-P