[Federal Register Volume 59, Number 195 (Tuesday, October 11, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-25059]
[[Page Unknown]]
[Federal Register: October 11, 1994]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 94-NM-155-AD]
Airworthiness Directives; Canadair Model CL-600-2B19 (Regional
Jet Series 100) Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the supersedure of an existing
airworthiness directive (AD), applicable to certain Canadair Model CL-
600-2B19 series airplanes, that currently requires a revision to the
Airplane Flight Manual (AFM) to restrict altitude and airspeed
operations of the airplane under certain conditions of hydraulic system
failure. This action would add a requirement to remove certain shear
pins and install certain new shear pins on the elevator flutter
dampers, and replace certain shear pins at repetitive intervals. This
proposal is prompted by the development of a temporary repair that
entails repetitive replacement of discrepant pins in a timely manner to
prevent failure of the pins. The actions specified by the proposed AD
are intended to prevent undampened vibration of the elevators in normal
cruise conditions; when combined with hydraulic system failures, this
condition could result in reduced controllability of the airplane.
DATES: Comments must be received by December 6, 1994.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-155-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., Canadair, Aerospace Group, P.O. Box
6087 Station Centre-ville, Montreal, Quebec H3C 3G9, 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, 181
South Franklin Avenue, Valley Stream, New York.
FOR FURTHER INFORMATION CONTACT: Franco Pieri, Aerospace Engineer,
Airframe Branch, ANE-172, New York Aircraft Certification Office, FAA,
Engine and Propeller Directorate, 181 South Franklin Avenue, Room 202,
Valley Stream, New York 11581; telephone (516) 791-6221; fax (516) 791-
9024.
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 statement is made: ``Comments
to Docket Number 94-NM-155-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-103, Attention: Rules
Docket No. 94-NM-155-AD, 1601 Lind Avenue SW., Renton, Washington
98055-4056.
Discussion
On January 3, 1994, the FAA issued AD 94-01-09, amendment 39-8791
(59 FR 1471, January 11, 1994), applicable to certain Canadair Model
CL-600-2B19 (Regional Jet Series 100) series airplanes, to require a
revision to the Limitations Section of the FAA-approved Airplane Flight
Manual (AFM) to restrict altitude and airspeed operations of the
airplane under certain conditions of hydraulic system failure. That
action was prompted by a report of sheared-off shear pins found on one
airplane's elevator dampers. The requirements of that AD are intended
to prevent undampened vibration of the elevators in normal cruise
conditions; when combined with hydraulic system failures, this
condition can result in reduced controllability of the airplane.
Since the issuance of that AD, Bombardier, Inc., has developed a
temporary repair, which involves removing the existing shear pins and
installing new shear pins on the elevator flutter dampers, and then
replacing the shear pins at repetitive intervals. The intent of this
temporary repair is to replace discrepant pins in a timely manner in
order to prevent the failure of the pins. (The manufacturer is
currently developing a permanent modification.) Failure of the shear
pins on the elevator damper, if not detected and corrected, may lead to
undampened vibration of the elevators during normal cruise conditions;
when combined with hydraulic system failures, this situation could
result in reduced controllability of the airplane.
Bombardier has issued Canadair ``Regional Jet'' Service Bulletin
S.B. 601R-27-017, dated May 12, 1994, which describes procedures for
accomplishing a temporary repair that entails the removal of shear pins
having part number (P/N) HST22DU8-13, and the installation of new shear
pins having P/N 601R24063-2501, on the elevator flutter dampers. This
service bulletin also describes procedures for replacement of the new
shear pins at repetitive intervals. Transport Canada Aviation, which is
the airworthiness authority for Canada, classified this service
bulletin as mandatory and issued Canadian Airworthiness Directive CF-
93-32R1, dated August 12, 1994, in order to assure the continued
airworthiness of these airplanes in Canada.
This airplane model is manufactured in Canada 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, Transport Canada Aviation has kept
the FAA informed of the situation described above. The FAA has examined
the findings of Transport Canada Aviation, 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.
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 supersede AD 94-01-09 to
require removal of existing shear pins and installation of certain new
shear pins on the elevator flutter dampers; and to require replacement
of shear pins at repetitive intervals. The actions would be required to
be accomplished in accordance with the service bulletin described
previously.
The proposed AD would also continue to require the previously-
required revision to the Limitations Section of the FAA-approved AFM to
restrict altitude and airspeed operations under conditions of single or
double hydraulic failure.
This is considered interim action until final action is identified,
at which time the FAA may consider additional rulemaking.
The FAA estimates that 19 airplanes of U.S. registry would be
affected by this proposed AD.
The AFM revision that was previously required by AD 94-01-09, and
retained in this proposal, takes approximately 1 work hour per airplane
to accomplish, at an average labor rate of $55 per work hour. Based on
these figures, the total cost impact of the AFM revision requirement on
U.S. operators is estimated to be $55 per airplane. The FAA estimates
that all affected U.S. operators have previously accomplished this
requirement; therefore, the future cost impact of this requirement is
minimal.
The removal, installation, and replacement of shear pins that would
be required by this proposal would take approximately 5 work hours per
airplane to accomplish, at an average labor rate of $55 per work hour.
Required parts would be supplied by the manufacturer at no cost to
operators. Based on these figures, the total cost impact of these
proposed requirement on U.S. operators is estimated to be $5,225, or
$275 per airplane.
The total 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.
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. App. 1354(a), 1421 and 1423; 49 U.S.C.
106(g); and 14 CFR 11.89.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing amendment 39-8791 (59 FR
1471, January 11, 1994), and by adding a new airworthiness directive
(AD), to read as follows:
Bombardier, Inc. (Formerly Canadair): Docket 94-NM-155-AD.
Supersedes AD 94-01-09, Amendment 39-8791.
Applicability: Model CL-600-2B19 (Regional Jet Series 100)
series airplanes; serial numbers 7003 and subsequent; certificated
in any category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent undampened vibration of the elevators in normal
cruise conditions which, when combined with hydraulic system
failures, could result in reduced controllability of the airplane,
accomplish the following:
(a) Within 30 days after January 26, 1994 (the effective date of
AD 94-01-09, amendment 39-8791), revise the Limitations Section of
the FAA-approved Airplane Flight Manual (AFM) to include the
following restrictions of altitude and airspeed operations under
conditions of single or double hydraulic system failure; and advise
the flight crew of these revised limits. Revision of the AFM may be
accomplished by inserting a copy of this AD in the AFM.
Note 1: The restrictions described in the AFM Temporary Revision
(TR) RJ/30 meet the requirements of this paragraph. Therefore,
inserting a copy of TR RJ/30 in lieu of this AD in the AFM is
considered an acceptable means of compliance with this paragraph.
Single Hydraulic System Failure
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Airspeed limit
Altitude limit (maximum) (maximum)
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31,000 feet-........................................ 0.55 Mach
(199 KIAS)
30,000 feet-........................................ 0.55 Mach
(204 KIAS)
28,000 feet......................................... 0.55 Mach
(213 KIAS)
26,000 feet-........................................ 0.55 Mach
(222 KIAS)
24,000 feet-........................................ 0.55 Mach
(232 KIAS)
22,000 feet-........................................ 0.55 Mach
(241 KIAS)
20,000 feet and below............................... 252 KIAS
------------------------------------------------------------------------
Double Hydraulic System Failure
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Airspeed Limit
Altitude Limit (maximum) (maximum)
------------------------------------------------------------------------
10,000 feet-........................................ 200 KIAS
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(b) For airplanes having serial numbers 7003 through 7044,
inclusive: Within 45 days after the effective date of this AD,
remove shear pins having part number (P/N) HST22DU8-13 that are
installed on the elevator flutter dampers, and install new shear
pins having P/N 601R24063-2501, in accordance with Canadair Regional
Jet Service Bulletin S.B. 601R-27-017, dated May 12, 1994.
Thereafter, prior to the accumulation of 800 flight hours on any
shear pin having P/N 601R24063-2501, replace it with a new shear pin
having P/N 601R24063-2501.
(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, Standardization Branch, ANM-113,
FAA, Transport Airplane Directorate. Operators shall submit their
requests through an appropriate FAA Principal Maintenance Inspector,
who may add comments and then send it to the Manager,
Standardization Branch, ANM-113.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Standardization Branch, ANM-113.
(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. Issued in Renton,
Washington, on October 4, 1994.
S.R. Miller, Acting Manager,
Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 94-25059 Filed 10-7-94; 8:45 am]
BILLING CODE 4910-13-U
