[Federal Register Volume 64, Number 66 (Wednesday, April 7, 1999)]
[Rules and Regulations]
[Pages 16803-16805]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-8328]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-04-AD; Amendment 39-11109; AD 99-08-04]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Bombardier Model DHC-8-100, -200, and -300 series 
airplanes, that 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 amendment is prompted by a report that 
the door lock mechanism of the flight compartment door jammed and could 
not be opened using the alternate release mechanism. The actions 
specified by this AD are intended to prevent failure of the alternate 
release mechanism of the flight

[[Page 16804]]

compartment door, which could delay or impede the evacuation of the 
flightcrew during an emergency. Such failure also could result in the 
flightcrew not being able to assist passengers in the event of an 
emergency.

DATES: Effective May 12, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 12, 1999.

ADDRESSES: The service information referenced in this AD may be 
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, 
Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This information 
may be examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, Engine and Propeller Directorate, New York 
Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley 
Stream, New York; or at the Office of the Federal Register, 800 North 
Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Ezra Sasson, Aerospace Engineer, 
Systems and Equipment Branch, ANE-172, FAA, New York Aircraft 
Certification Office, Engine and Propeller Directorate, 10 Fifth 
Street, Third Floor, Valley Stream, New York 11581; telephone (516) 
256-7520; fax (516) 568-2716.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain Bombardier Model DHC-8-
100, -200, and -300 series airplanes was published as a supplemental 
notice of proposed rulemaking (NPRM) in the Federal Register on August 
5, 1998 (63 FR 41741). That action proposed to require 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.

Comments Received

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for Proposed Rule

    One commenter supports the proposed rule.

Request to Revise Applicability Statement

    One commenter requests that the applicability statement of the 
proposed AD be revised to reflect the effectivity listing specified in 
Bombardier Service Bulletin S.B. 8-52-39, Revision `D,' dated February 
27, 1998 (i.e., Model DHC-8 series airplanes having serial numbers 003 
through 433 inclusive, except serial numbers 269, 408, and 413). The 
commenter points out that paragraph (a) of the proposed AD requires 
accomplishment of the modification specified in the subject service 
bulletin.
    The FAA does not concur with the commenter's request. The 
applicability statement of the original NPRM [which was published in 
the Federal Register on July 11, 1997 (62 FR 37170)] read, ``Model DHC-
8-100, -200, and -300 series airplanes having serial numbers 3 through 
433 inclusive, excluding serial numbers 269, 408, and 418; certificated 
in any category.'' The FAA revised the applicability of the 
supplemental NPRM in consonance with the Canadian airworthiness 
directive CF-96-20R2, dated July 16, 1997. This revision was made 
because the supplemental NPRM was revised to add repetitive inspections 
for wear of the flight compartment door hinges following accomplishment 
of the required modification. These new repetitive inspections must be 
accomplished on all affected airplanes having serial numbers 3 and 
subsequent, regardless of whether the airplane has been modified.

Explanation of Changes Made to Supplemental NPRM

    The FAA has revised the final rule to reflect the corporate name 
change of de Havilland, Inc. to Bombardier, Inc.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Interim Action

    This is considered to be interim action. The manufacturer has 
advised the FAA that it currently is developing a modification that 
will eliminate the need for the repetitive inspections for wear of the 
flight compartment door hinges. Once this modification is developed, 
approved, and available, the FAA may consider additional rulemaking.

Cost Impact

    The FAA estimates that 133 Bombardier Model DHC-8-100, -200, and -
300 series airplanes of U.S. registry will be affected by this AD.
    It will take approximately 4 work hours per airplane to accomplish 
the required modification, at an average labor rate of $60 per work 
hour. Required parts will be provided by the manufacturer at no cost to 
operators. Based on these figures, the cost impact of the modification 
required by this AD on U.S. operators is estimated to be $31,920, or 
$240 per airplane.
    It will take approximately 2 work hours per airplane to accomplish 
the required inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the inspection required by 
this AD on U.S. operators is estimated to be $15,960, or $120 per 
airplane, per inspection cycle.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it 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, Incorporation by 
reference, Safety.

[[Page 16805]]

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:

99-08-04  Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 
39-11109. Docket 97-NM-04-AD.

    Applicability: Model DHC-8-100, -200, and -300 series airplanes 
having serial numbers 3 and subsequent; certificated in any 
category.
    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
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 (c) 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 alternate release mechanism of the 
flight compartment door, which could delay or impede the evacuation 
of the flightcrew and passengers during an emergency, accomplish the 
following:
    (a) Within 90 days after the effective date of this AD, 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.

    Note 2: Modification of the flight compartment door accomplished 
prior to the effective date of this AD 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; is considered acceptable for 
compliance with the modification required by paragraph (a) of this 
AD.

    (b) Within 800 flight hours after accomplishment of the 
modification required by paragraph (a) 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 `C,' dated September 1, 1997, or Revision `D,' dated 
February 27, 1998.
    (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.

Alternative Methods of Compliance

    (c) 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, Engine and Propeller Directorate. 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 3: 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

    (d) 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.

Incorporation by Reference

    (e) The actions shall be done in accordance with Bombardier 
Service Bulletin S.B. 8-52-39, Revision `C,' dated September 1, 
1997, and Bombardier Service Bulletin S.B. 8-52-39, Revision `D,' 
dated February 27, 1998; as applicable. This incorporation by 
reference was approved by the Director of the Federal Register in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from Bombardier, Inc., Bombardier Regional Aircraft 
Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. 
Copies may be inspected at the FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and 
Propeller Directorate, New York Aircraft Certification Office, 10 
Fifth Street, Third Floor, Valley Stream, New York; or at the Office 
of the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.
    Note 4: The subject of this AD is addressed in Canadian 
airworthiness directive CF-96-20R2, dated July 16, 1997.

    (f) This amendment becomes effective on May 12, 1999.

    Issued in Renton, Washington, on March 30, 1999.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-8328 Filed 4-6-99; 8:45 am]
BILLING CODE 4910-13-P