[Federal Register Volume 59, Number 182 (Wednesday, September 21, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-23327]
[[Page Unknown]]
[Federal Register: September 21, 1994]
VOL. 59, NO. 182
Wednesday, September 21, 1994
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 94-NM-127-AD]
Airworthiness Directives; de Havilland Model DHC-8-100 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 de Havilland Model DHC-8-
100 and -300 series airplanes. This proposal would require an
inspection to verify the integrity of the shield grounds for the cable
harness of the electronic engine control (EEC), and correction of any
discrepancy. This proposal also would require measurement of the
electrical resistance of certain shield grounds, and repair, if
necessary. This proposal is prompted by a report of an engine flameout
after a lightning strike, due to several shields for the cable harness
of the EEC not being properly grounded to the airframe. The actions
specified by the proposed AD are intended to prevent engine flameout
due to insufficient protection of the EEC.
DATES: Comments must be received by October 31, 1994.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 94-NM-127-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, Canada M3K 1Y5. 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, Room 202, Valley Stream, New York.
FOR FURTHER INFORMATION CONTACT: Richard Fiesel, Aerospace Engineer,
Propulsion Branch, ANE-174, FAA, Engine and Propeller Directorate, New
York Aircraft Certification Office, 181 South Franklin Avenue, Room
202, Valley Stream, New York 11581; telephone (516) 791-7421; 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-127-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-127-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
On April 25, 1989, the FAA issued AD 85-14-51 R2, amendment 39-6207
(54 FR 19875, May 9, 1989), which is applicable to certain de Havilland
Model DHC-8-100 series airplanes. That AD requires revising the
Limitations Section of the FAA-approved Airplane Flight Manual (AFM) to
prohibit takeoff, landing, and climb in the vicinity of lightning or
thunderstorms; and to require continuous ignition operation during
takeoffs, takeoff climb to 1500 feet above ground level, final
approach, and landing within 5 nautical miles of lightning and
thunderstorms. That AD also requires the installation of four
modifications designed to protect the electronic engine control (EEC)
from the effects of lightning strike, which, when accomplished,
terminates the requirements of that AD and allows for the removal of
the AFM limitations.
Since issuance of that AD, Transport Canada Aviation, which is the
airworthiness authority for Canada, has advised the FAA of a report of
an engine flameout after a lightning strike on a Model DHC-8 series
airplane. Modifications required by AD 85-14-51 R2 had been
accomplished on that airplane. Investigation revealed that the engine
flameout occurred because several shields for the cable harness of the
EEC were not properly grounded to the airframe. This condition, if not
corrected, could result in insufficient protection of the EEC and may
lead to an engine flameout following a lightning strike.
Bombardier has issued Service Bulletins S.B. 8-73-18 (for Model
DHC-8-100 series airplanes) and S.B. 8-73-19 (for Model DHC-8-300
series airplanes), both dated April 29, 1994, which describe procedures
for a visual inspection to verify the integrity of the shield grounds
for the cable harness of the EEC, and correction of any discrepancy.
The service bulletins also describe procedures for measurement of the
electrical resistance of certain shield grounds, and repair, if
necessary. The repair procedures consist of ensuring that the metal
overbraid (which provides lightning protection for the EEC cable
harness) is electrically bonded to the connector and the electrical
receptacles are electrically bonded to the airframe. Transport Canada
Aviation classified these service bulletins as mandatory and issued
Canadian Airworthiness Directive CF-94-09, dated May 5, 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 require a visual inspection
to verify the integrity of the shield grounds for the cable harness of
the EEC, and correction of any discrepancy. This AD also would require
measurement of the electrical resistance of certain shield grounds, and
repair, if necessary. The actions would be required to be accomplished
in accordance with the service bulletins described previously.
The FAA estimates that 141 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 16 work
hours per airplane to accomplish the proposed actions, and that the
average labor rate is $55 per work hour. Based on these figures, the
total cost impact of the proposed AD on U.S. operators is estimated to
be $124,080, or $880 per airplane.
The total cost impact figure discussed above is 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 adding the following new
airworthiness directive:
De Havilland, Inc.: 94-NM-127-AD.
Applicability: Model DHC-8-102, -103, and -106 series airplanes,
serial numbers 3 through 369 inclusive; and Model DHC-8-301, -311,
and -314 series airplanes, serial numbers 100 through 370 inclusive;
certificated in any category.
Compliance: Required as indicated, unless accomplished
previously.
To prevent engine flameout following a lightning strike,
accomplish the following:
(a) Within 45 days after the effective date of this AD, perform
a visual inspection of the mounting clamps and ``breakout
junctions'' in the metal overbraid to verify the integrity of the
shield grounds for the cable harness of the electronic engine
control (EEC), in accordance with de Havilland Service Bulletin S.B.
8-73-18 (for Model DHC-8-100 series airplanes), or S.B. 8-73-19 (for
Model DHC-8-300 series airplanes), both dated April 29, 1994, as
applicable. If any discrepancy is found, prior to further flight,
correct the discrepancy in accordance with the applicable service
bulletin.
(b) Within 45 days after the effective date of this AD, perform
an electrical resistance measurement of Class A and Class B shield
grounds in accordance with de Havilland Service Bulletin S.B. 8-73-
18 (for Model DHC-8-100 series airplanes), or S.B. 8-73-19 (for
Model DHC-8-300 series airplanes), both dated April 29, 1994, as
applicable.
(1) For Class A shield grounds: If the electrical resistance
exceeds the value specified in the service bulletin, within 50
flight hours after performing the resistance measurement repair in
accordance with the applicable service bulletin.
(2) For Class B shield grounds: If the electrical resistance
exceeds the value specified in the service bulletin, within 180 days
after performing the resistance measurement repair in accordance
with the applicable service bulletin.
(c) For Model DHC-8-102, -103, and -106 series airplanes on
which an interim shield ground is installed in accordance with
paragraphs 19 and 93 of the Accomplishment Instructions of de
Havilland Service Bulletin S.B. 8-73-18, dated April 29, 1994:
Within one year after the effective date of this AD, restore the
airplane to the Post-Modification 8/0772 configuration in accordance
with paragraph 161 of the Accomplishment Instructions of that
service bulletin.
(d) For Model DHC-8-301, -311, and -314 series airplanes on
which an interim shield ground is installed in accordance with
paragraphs 19 and 112 of the Accomplishment Instructions of de
Havilland Service Bulletin S.B. 8-73-19, dated April 29, 1994:
Within one year after the effective date of this AD, restore the
airplane to the Post-Modification 8/0772 configuration in accordance
with paragraph 200 of the Accomplishment Instructions of that
service bulletin.
(e) 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), ANE-170, 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: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the New York ACO.
(f) 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 September 15, 1994.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 94-23327 Filed 9-20-94; 8:45 am]
BILLING CODE 4910-13-U