[Federal Register Volume 63, Number 150 (Wednesday, August 5, 1998)]
[Proposed Rules]
[Pages 41741-41743]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-20833]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-NM-04-AD]
RIN 2120-AA64
Airworthiness Directives; de Havilland Model DHC-8-100, -200, and
-300 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Supplemental notice of proposed rulemaking; reopening of
comment period.
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SUMMARY: This document revises an earlier proposed airworthiness
directive (AD), applicable to certain de Havilland Model DHC-8-100, -
200, and -300 series airplanes, that would have required modification
of the flight compartment door. That proposal was 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. This new
action would add 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 new
action also revises the applicability of the existing AD. The actions
specified by this new proposed AD are intended 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. Such failure also could result in the flightcrew not being
able to assist passengers in the event of an emergency.
DATES: Comments must be received by August 31, 1998.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 97-NM-04-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.
The service information referenced in the proposed rule may be
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division,
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 Engine and Propeller
Directorate, New York Aircraft Certification Office, 10 Fifth Street,
Third Floor, Valley Stream, New York.
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:
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 notice may be changed in
light of the comments received.
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 notice must submit a self-addressed,
stamped postcard on which the following
[[Page 41742]]
statement is made: ``Comments to Docket Number 97-NM-04-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 No. 97-NM-04-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
A proposal to amend part 39 of the Federal Aviation Regulations (14
CFR part 39) to add an airworthiness directive (AD), applicable to
certain de Havilland Model DHC-8-100, -200, and -300 series airplanes,
was published as a notice of proposed rulemaking (NPRM) in the Federal
Register on July 11, 1997 (62 FR 37170). That NPRM would have required
modification of the flight compartment door. That NPRM was prompted by
a report that the door lock mechanism of the flight compartment door
jammed and it could not be opened using the alternate release
mechanism. That condition, if not corrected, could result in failure of
the alternate release mechanism of the flight 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.
Actions Since Issuance of Previous Proposal
Since the issuance of that NPRM, the manufacturer has issued de
Havilland Service Bulletin S.B. 8-52-39, Revision `C,' dated September
1, 1997, and Revision `D,' dated February 27, 1998.
Among other things, Revision `C' revises the effectivity of the
earlier releases of the service bulletin. In addition, the
Accomplishment Instructions of the service bulletin have been revised
to include a section titled ``Special Inspection/Repair,'' which
describes procedures for repetitive inspections of the door hinges for
wear. For airplanes on which any wear is found that is greater than
0.050 inch in depth, the service bulletin describes procedures for
removal and replacement of the hinges with new hinges. For airplanes on
which any wear is found that is less than 0.050 inch, but greater than
0.020 inch in depth, the service bulletin describes procedures for
repair of the hinge.
Revision `D' is essentially identical to Revision `C;' however, it
provides information for an additional modification kit for certain
Model DHC-8-300 series airplanes with a forward galley where a -100
series lavatory has been installed.
Transport Canada Aviation, which is the airworthiness authority for
Canada, classified these service bulletin revisions as mandatory and
issued Canadian airworthiness directive CF-96-20R2, dated July 16,
1997, in order to assure the continued airworthiness of these airplanes
in Canada.
Changes to the Original NPRM
The FAA has determined that, in order to adequately address the
unsafe condition presented by problems associated with the flight
compartment door, the originally proposed rule must be revised to
require repetitive inspections for wear of the modified flight
compartment door hinges, and repair, if necessary. These additional
actions would be required to be accomplished in accordance with the
revised service bulletins described previously.
Additionally, the applicability of this supplemental NPRM has been
revised to correspond with the revised service bulletin effectivity
discussed previously.
Conclusion
Since these changes expand the scope of the originally proposed
rule, the FAA has determined that it is necessary to reopen the comment
period to provide additional opportunity for public comment.
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 de Havilland Model DHC-8-100, -200, and
-300 series airplanes of U.S. registry would be affected by this
proposed AD.
It would take approximately 4 work hours per airplane to accomplish
the proposed modification, at an average labor rate of $60 per work
hour. Required parts would be provided by the manufacturer at no cost
to operators. Based on these figures, the cost impact of the
modification proposed by this AD on U.S. operators is estimated to be
$31,920, or $240 per airplane.
It would take approximately 2 work hours per airplane to accomplish
the proposed inspection, at an average labor rate of $60 per work hour.
Based on these figures, the cost impact of the inspection proposed 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 proposed 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 proposed herein would 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
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
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.
[[Page 41743]]
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new
airworthiness directive:
De Havilland, Inc.: 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 de Havilland
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 de
Havilland 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 de Havilland 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.
(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.
(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.
Note 4: The subject of this AD is addressed in Canadian
airworthiness directive CF-96-20R2, dated July 16, 1997.
Issued in Renton, Washington, on July 29, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-20833 Filed 8-4-98; 8:45 am]
BILLING CODE 4910-13-U
