AD Amdt-39-10546

[Federal Register Volume 63, Number 104 (Monday, June 1, 1998)]
[Rules and Regulations]
[Pages 29546-29547]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 98-14025]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 96-NM-58-AD; Amendment 39-10546; AD 98-11-21]
RIN 2120-AA64


Airworthiness Directives; de Havilland Model DHC-8-102, -103, and 
-301 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 de Havilland Model DHC-8-102, -103, and -301 
series airplanes, that requires a one-time inspection for wear and 
breakage of wire segments of the individual lighting units of the 
ceiling and sidewall lights, and replacement of any damaged wiring. 
This amendment also requires installation of teflon spiral wrap on the 
wiring of the ceiling and sidewall lights. This amendment is prompted 
by reports of chafing found on the electrical wiring of the cabin 
ceiling lighting system. The actions specified by this AD are intended 
to prevent the possibility of a fire on an airplane due to such chafing 
and consequent short circuiting, overheating, and smoking of the wires 
on the aircraft structure.

DATES: Effective July 6, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of July 6, 1998.

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, 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: Peter Cuneo, Electrical Engineer, New 
York Aircraft Certification Office, Systems & Flight Test Branch (ANE-
172), FAA, Engine and Propeller Directorate, 10 Fifth Street, Third 
Floor, Valley Stream, New York 11581-1200; telephone (516) 256-7506; 
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 de Havilland Model DHC-8-
102, -103, and -301 series airplanes was published in the Federal 
Register on September 13, 1996 (61 FR 48437). That action proposed to 
require a one-time inspection for wear and breakage of wire segments of 
the individual lighting units of the ceiling and sidewall lights, and 
replacement of any damaged wiring. That action also proposed to require 
installation of teflon spiral wrap on the wiring of the ceiling and 
sidewall lights.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.
    One commenter, an aerospace lighting manufacturer, requests that 
the proposed rule be revised to require, as a first step, an initial 
inspection of the entire cabin lighting system, and repetitive 
inspections of the entire cabin lighting system after a fixed number of 
flight hours after a trigger event such as any lighting component 
failure. The commenter contends that, despite initial inspections and 
installation of secondary insulation, cases of fire or smoke caused by 
arcing from fluorescent lighting high voltage wiring have continued in 
other airplane models. Further, the commenter notes that an existing AD 
[AD 95-08-04, amendment 39-9193, (60 FR 19348, April 18, 1995)] was 
issued for a similar electrical arcing problem of the fluorescent 
lighting system connector and requires an inspection and modification 
of some connectors. However, the commenter asserts that the requirement 
for repetitive inspections is not the total answer in preventing cases 
of fire or smoke due to arcing from fluorescent lighting high voltage 
wiring. An additional step would be to require certain protection 
circuitry for the fluorescent lighting systems that would provide for 
terminating action of the repetitive inspections. The commenter 
suggests that, since certain protection circuitry for fluorescent 
lighting components has been approved by the FAA, is in use on several 
different airplanes, and has had no negative in-service reports, the 
FAA should consider requiring installation of such protection circuitry 
as a terminating action for the requirements of the proposed rule.
    The FAA does not concur that installation of protection circuitry 
should be required in this case. The FAA finds that, based on 
information provided by the airplane manufacturer, installation of the 
Teflon spiral wrap will provide an adequate level of safety. No change 
to the final rule is necessary. However, the FAA may approve a request 
for an alternative method of compliance under the provisions of 
paragraph (b) of this final rule if data are submitted to substantiate 
that an equivalent level of safety would be provided.
    In regard to the commenter's reference to AD 95-08-04, the FAA 
acknowledges that the unsafe condition of both AD's are similar 
(possibility of a fire on an airplane). However, the FAA has determined 
that the causes of the unsafe condition are not the same. The earlier 
existing AD addresses a component failure in the high voltage circuitry 
of

[[Page 29547]]

the lighting system as the cause of the unsafe condition; this AD 
addresses chafed wires in the 28VdC supply side of the lighting system 
as the cause of the unsafe condition. Therefore, the FAA finds that it 
is logical and practical that the actions required to correct the 
unsafe condition are not necessarily identical to each other.

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 as proposed.

Cost Impact

    The FAA estimates that 73 de Havilland Model DHC-8-102, -103, and 
301 series airplanes of U.S. registry will be affected by this proposed 
AD, that it will take approximately 30 work hours per airplane to 
accomplish the required actions, and that the average labor rate is $60 
per work hour. Required parts will cost approximately $250 per 
airplane. Based on these figures, the cost impact of the AD on U.S. 
operators is estimated to be $149,650, or $2,050 per airplane.
    The cost impact figure discussed above is 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.

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:

98-11-21  De Havilland, Inc.: Amendment 39-10546. Docket 96-NM-58-
AD.

    Applicability: Model DHC-8-102, -103, and -301 series airplanes; 
serial numbers 002 though 010 inclusive, 012 through 201 inclusive, 
203 through 209 inclusive, 211 through 215 inclusive, 217 through 
220 inclusive, 222, and 223; on which de Havilland Modification 8/
1114 or 8/1110 (reference de Havilland Service Bulletin S.B. 8-33-
35) has not been accomplished; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 (b) 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 the possibility of a fire on an airplane due to 
chafing of the electrical wiring of the cabin ceiling lighting 
system, accomplish the following:
    (a) Within 1,000 hours time-in-service or 6 months after the 
effective date of this AD, whichever occurs first: Accomplish the 
requirements of paragraphs (a)(1) and (a)(2) of this AD in 
accordance with de Havilland Service Bulletin S.B. 8-33-35, dated 
September 1, 1995.
    (1) Perform a one-time inspection for wear and breakage of wire 
segments of the individual lighting units of the ceiling and 
sidewall lights. Prior to further flight, replace any damaged 
wiring.
    (2) Install teflon spiral wrap on the wiring of the ceiling and 
sidewall lights (Modification 8/2158).
    (b) 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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the New York ACO.

    (c) 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.
    (d) The actions shall be done in accordance with de Havilland 
Service Bulletin S.B. 8-33-35, dated September 1, 1995. 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 
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 3: The subject of this AD is addressed in Canadian 
airworthiness directive CF-95-18, dated December 15, 1995.

    (e) This amendment becomes effective on July 6, 1998.

    Issued in Renton, Washington, on May 20, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-14025 Filed 5-29-98; 8:45 am]
BILLING CODE 4910-13-U