[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