[Federal Register Volume 62, Number 244 (Friday, December 19, 1997)]
[Proposed Rules]
[Pages 66561-66563]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-33143]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-CE-46-AD]
RIN 2120-AA64
Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and
PC-12/45 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes to adopt a new airworthiness directive
(AD) that would apply to certain Pilatus Aircraft Ltd. (Pilatus) Models
PC-12 and PC-12/45 airplanes. The proposed action would require
installing aluminum bonding bushings over certain screws in certain
fuel tank underwing access panels. Several reports from the field
revealing fuel tank access panels insufficiently electrically bonded to
the airframe prompted this proposed AD. The actions specified by
[[Page 66562]]
the proposed AD are intended to prevent electrical arcing in the fuel
tanks and detonation of the fuel-air mixture, which can be created by
poor electrical bonding of fuel tank underwing access panels, and if
not corrected, could result in a fire on the airplane.
DATES: Comments must be received on or before February 20, 1998.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Central Region, Office of the Regional Counsel,
Attention: Rules Docket No. 97-CE-46-AD, Room 1558, 601 E. 12th Street,
Kansas City, Missouri 64106. Comments may be inspected at this location
between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted.
Service information that applies to the proposed AD may be obtained
from Pilatus Aircraft Ltd., CH-6370 Stans, Switzerland; telephone +41-
41-6196-233; facsimile +41-41-6103-351. This information also may be
examined at the Rules Docket at the address above.
FOR FURTHER INFORMATION CONTACT: Mr. Roman Gabrys, Project Officer,
FAA, Small Airplane Directorate, Aircraft Certification Service, 1201
Walnut, suite 900, Kansas City, Missouri 64106; telephone (816) 426-
6934; facsimile (816) 426-2169.
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 should 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 that summarizes 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 No. 97-CE-46-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, Central Region, Office of the Regional Counsel, Attention:
Rules Docket No. 97-CE-46-AD, Room 1558, 601 E. 12th Street, Kansas
City, Missouri 64106.
Discussion
The Federal Office for Civil Aviation (FOCA), which is the
airworthiness authority for Switzerland, recently notified the FAA that
an unsafe condition may exist on certain Pilatus Model PC-12 and PC-12/
45 airplanes. FOCA reports that during routine inspections of some of
these airplanes, the inspectors found that the underwing access panels
to the fuel tank were not sufficiently electrically bonded to the
airframe. These conditions, if not corrected, could result in
detonation of the airplane's fuel tanks by electrical arcing through
the fuel-air mixture.
Relevant Service Information
Pilatus Aircraft Ltd. has issued service bulletin (SB) No. 57-001,
dated February 28, 1997 which specifies procedures for installing
aluminum bonded bushings over the screws to the underwing fuel tank
access panels to assure a positive electrical bonding to the airframe
structure.
The FAA's Determination
This airplane model is manufactured in Switzerland and is type
certificated for operation in the United States under the provisions of
Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the
applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, FOCA has kept the FAA informed of
the situation described above. The FAA has examined the findings of
FOCA, reviewed all available information including the service
information referenced above, and determined that AD action is
necessary for products of this type design that are certificated for
operation in the United States.
Explanation of the Provisions of the Proposed AD
Since an unsafe condition has been identified that is likely to
exist or develop in other Pilatus Models PC-12 and PC-12/45 airplanes
of the same type design registered in the United States, the proposed
AD would require installing aluminum bonding bushes over the screws in
the fuel tank underwing access panels. Accomplishment of the proposed
action would be in accordance with Pilatus Service Bulletin No. 57-001,
dated February 28, 1997.
Cost Impact
The FAA estimates that 40 airplanes in the U.S. registry would be
affected by the proposed AD, that it would take approximately 6 work
hours per airplane to accomplish the proposed action, and that the
average labor rate is approximately $60 an hour. Parts would be
provided at no cost by the manufacturer. Based on these figures, the
total cost impact of the proposed AD on U.S. operators is estimated to
be $14,400, or $360 per airplane.
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 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) 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 has been placed 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:
[[Page 66563]]
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 a new airworthiness directive
(AD) to read as follows:
Pilatus Aircraft Ltd.: Docket No. 97-CE-46-AD.
Applicability: Model PC-12 and PC-12/45 airplanes (serial
numbers MSN 001 through MSN 168), 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 within the next 100 hours time-in-service
(TIS) after the effective date of this AD, unless already
accomplished.
To prevent electrical arcing in the fuel tanks and detonation of
the fuel-air mixture, which can be created by poor electrical
bonding of fuel tank underwing access panels, and if not corrected,
could result in a fire on the airplane, accomplish the following:
(a) Install aluminum bonding bushings onto the screws for
certain fuel tank underwing access panels in accordance with Part A
and Part B of the Accomplishment Instructions in Pilatus Aircraft
LTD PC12 Service Bulletin No. 57-001, dated February 28, 1997.
(b) 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.
(c) An alternative method of compliance or adjustment of the
compliance time that provides an equivalent level of safety may be
approved by the Manager, Small Airplane Directorate, Aircraft
Certification Service, 1201 Walnut, suite 900, Kansas City, Missouri
64106. The request shall be forwarded through an appropriate FAA
Maintenance Inspector, who may add comments and then send it to the
Manager, Small Airplane Directorate.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Small Airplane Directorate.
(d) All persons affected by this directive may obtain copies of
the document referred to herein upon request to Pilatus Aircraft
Ltd., CH-6370 Stans, Switzerland; or may examine this document at
the FAA, Central Region, Office of the Regional Counsel, Room 1558,
601 E. 12th Street, Kansas City, Missouri 64106.
Issued in Kansas City, Missouri, on December 11, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-33143 Filed 12-18-97; 8:45 am]
BILLING CODE 4910-13-U
