Airworthiness Directives; Pilatus Aircraft LTD Models PC-12 and PC-12/45 Airplanes
Requires modifying the generator 2 excitation by removing certain diodes and installing a new 5-amp circuit breaker and suppression filter on certain Pilatus Aircraft Ltd.
[Federal Register Volume 66, Number 109 (Wednesday, June 6, 2001)]
[Rules and Regulations]
[Pages 30300-30302]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-13580]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 99-CE-82-AD; Amendment 39-12243; AD 2001-11-02]
RIN 2120-AA64
Airworthiness Directives; Pilatus Aircraft LTD Models PC-12 and
PC-12/45 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes Airworthiness Directive (AD) 99-17-
08, which currently requires modifying the generator 2 excitation by
removing certain diodes and installing a new 5-amp circuit breaker and
suppression filter on certain Pilatus Aircraft Ltd. (Pilatus) Models
PC-12 and PC-12/45 airplanes. This AD is the result of the Federal
Aviation Administration's determination that the A250 voltage spike
suppression filter in the modification kit can cause the circuit
breaker 235 to trip because of overload. In extreme circumstances, this
can lead to overheating of wiring. This AD requires you to modify the
generator 2 excitation by removing certain diodes and installing a new
5-amp circuit breaker and suppression filter of improved design in
accordance with revised procedures. This AD is the result of mandatory
continuing airworthiness information (MCAI) issued by the airworthiness
authority for Switzerland. The actions specified by this AD are
intended to prevent damage to electrical components if generator 2 is
not switched off before engine shutdown and it overheats. This could
result in loss of electrical power to certain critical airplane
components.
DATES: This AD becomes effective on July 23, 2001.
The Director of the Federal Register approved the incorporation by
reference of Pilatus Service Bulletin No. 24-014, dated October 27,
1999, as of July 23, 2001.
The Director of the Federal Register previously approved the
incorporation by reference of Pilatus Service Bulletin No. 24-012,
dated February 19, 1999, as of October 4, 1999 (64 FR 45149, August 19,
1999).
ADDRESSES: You may get the service information referenced in this AD
from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans,
Switzerland; telephone: +41 41 619 65 09; facsimile: +41 41 610 33 51.
You may examine this information at the Federal Aviation Administration
(FAA), Central Region, Office of the Regional Counsel, Attention: Rules
Docket No. 99-CE-82-AD, 901 Locust, Room 506, Kansas City, Missouri
64106; or at the Office of the Federal Register, 800 North Capitol
Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA,
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri
64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.
SUPPLEMENTARY INFORMATION:
Discussion
Has FAA Taken Any Action to This Point?
The FAA issued AD 99-17-08, Amendment 39-11256 (64 FR 45149, August
19, 1999), against Pilatus models PC-12 and PC-12/45 airplanes, to
prevent damage to electrical components if generator 2 is not switched
off before engine shutdown and it overheats. This could result in loss
of electrical power to certain critical airplane components.
AD 99-17-08 requires that you do the following on the affected
airplanes:
--modify the generator 2 excitation by removing certain diodes; and
--install a new 5-amp circuit breaker and suppression filter.
AD 99-17-08 was the result of mandatory continuing airworthiness
information (MCAI) issued by the airworthiness authority for
Switzerland.
What Has Happened Since AD 99-17-08 To Begin This Action?
The Federal Office for Civil Aviation (FOCA), which is the
airworthiness authority for Switzerland, notified the FAA of the need
to change AD 99-17-08. The FOCA reports that after installation of the
modification kit in accordance with Pilatus Service Bulletin SB 24-012
and turning on electrical power on one of the affected airplanes, the
circuit breaker CB 235 tripped.
Investigation revealed that the suppression filter (A250) (part
number 524.52.12.358) was shorted. The suppression diode installed in
the filter was shorted and was the wrong type. The manufacturer's A250
voltage spike suppression filter is inadequate and has been replaced
with an A250 voltage spike suppression filter of improved design.
Has FAA Taken Any Action to This Point?
We issued a proposal to amend part 39 of the Federal Aviation
Regulations (14 CFR part 39) to include an AD that would apply to
certain Pilatus Models PC-12 and PC-12/45 airplanes. This proposal was
published in the Federal Register as a notice of proposed rulemaking
(NPRM) on March 5, 2001 (66 FR 13271). The NPRM proposed to supersede
AD 99-17-08, Amendment 39-11256 (64 FR 45149, August 19, 1999). The
NPRM also proposed to require you to modify the generator 2 excitation
by removing certain diodes and installing a new 5-amp circuit breaker
and suppression filter of improved design in accordance with revised
procedures.
Was the Public Invited To Comment?
Interested persons were afforded an opportunity to participate in
the making of this amendment. No comments were received on the proposed
rule or the FAA's determination of the cost to the public.
FAA's Determination
What Is FAA's Final Determination on This Issue?
After careful review of all available information related to the
subject
[[Page 30301]]
presented above, we have determined that air safety and the public
interest require the adoption of the rule as proposed except for minor
editorial corrections. We determined that these minor corrections:
--Will not change the meaning of the AD; and
--Will not add any additional burden upon the public than was already
proposed.
Cost Impact
How Many Airplanes Does This AD Impact?
We estimate that this AD affects 69 airplanes in the U.S. registry.
What Is the Cost Impact of This AD on Owners/Operators of the Affected
Airplanes?
We estimate the following costs to do the modification of the
generator 2 excitation:
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Total cost per Total cost on
Labor cost Parts cost airplane U.S. operators
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8 workhours x $60 per hour = $480....... Parts will be provided at no cost $480 $33,120
to the owners/operators of the
affected aircraft.
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If the modification of the generator 2 excitation has been done
with the manufacturer's modification kit, then we estimate the
following costs to remove the A250 voltage spike suppression filter and
replace it with the new A250 voltage spike suppression filter:
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Total cost per Total cost on
Labor cost Parts cost airplane U.S. operators
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3 workhours x $60 per hour = $180....... Parts will be provided at no cost $180 $12,420
to the owners/operators of the
affected aircraft.
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Regulatory Impact
Does This AD Impact Various Entities?
The regulations adopted herein will not have a substantial direct
effect 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, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
Does This AD Involve a Significant Rule or Regulatory Action?
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 copy of the final 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, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under 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. FAA amends Sec. 39.13 by removing airworthiness directive (AD)
99-17-08, Amendment 39-11256 (64 FR 45149, August 19, 1999), and by
adding a new AD to read as follows:
2001-11-02 Pilatus Aircraft Ltd.: Amendment 39-12243; Docket No.
99-CE-82-AD, Supersedes AD 99-17-08, Amendment 39-11256.
(a) What airplanes are affected by this AD? This AD affects
Models PC-12 and PC-12/45 airplanes, serial numbers 101 through 289,
that are certificated in any category.
(b) Who must comply with this AD? Anyone who wishes to operate
any of the above airplanes must comply with this AD.
(c) What problem does this AD address? The actions specified by
this AD are intended to prevent damage to electrical components if
generator 2 is not switched off before engine shutdown and it
overheats. This could result in loss of electrical power to certain
critical airplane components.
(d) What actions must I accomplish to address this problem? To
address this problem, you must accomplish the following:
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Actions Compliance Procedures
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(1) Modify the generator 2 Within the next 100 Do this action
excitation with the hours time-in- following the
modification kit, part service (TIS) after ACCOMPLISHMENT
number (P/N) 500.50.12.192, July 23, 2001 (the INSTRUCTIONS
which requires you to: effective date of section of Pilatus
(i) Remove certain diodes; this AD), unless Service Bulletin
(ii) Install a new 5-ramp already done. No. 24-012, dated
circuit breaker, P/N February 19, 1999,
972.55.18.406; and and Service
(iii) Install an A250 Bulletin No. 24-
voltage spike suppression 014, dated October
filter, P/N 524.52.12.502, 27, 1999.
which replaces P/N
524.52.358
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[[Page 30302]]
(2) If the modification kit, Within the next 100 Do this action
part number 500.50.12.192, hours TIS after following the
is already installed using July 23, 2001 (the ACCOMPLISHMENT
the A250 voltage spike effect date of this INSTRUCTIONS
suppression filter, part AD), unless already section of Pilatus
number 524.52.12.358, done. Service Bulletin
replace only this voltage No. 24-014, dated
spike suppression filter October 27, 1999.
with a new A250 voltage
spike suppression filter,
part number 524.52.12.502.
(3) Do not install any A250 As of July 23, 2001 Not Applicable.
voltage spike suppression (the effective date
filter, part number of this AD).
524.52.358, or FAA-approved
equivalent part number.
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(e) Can I comply with this AD in any other way? You may use an
alternative method of compliance or adjust the compliance time if:
(1) Your alternative method of compliance provides an equivalent
level of safety; and
(2) The Manager, Small Airplane Directorate, approves your
alternative. Submit your request through an FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, Small Airplane Directorate.
(3) Alternative methods of compliance that were approved in
accordance with AD 99-17-08 are not considered approved as
alternative methods of compliance for this AD.
Note 1: This AD applies to each airplane identified in paragraph
(a) of this AD, 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 (e) 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 you have not eliminated the unsafe condition, specific
actions you propose to address it.
(f) Where can I get information about any already-approved
alternative methods of compliance? Contact Doug Rudolph, Aerospace
Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301,
Kansas City, Missouri 64106; telephone: (816) 329-4059; facsimile:
(816) 329-4090.
(g) What if I need to fly the airplane to another location to
comply with this AD? The FAA can issue a special flight permit under
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate your airplane to a location where
you can accomplish the requirements of this AD.
(h) Are any service bulletins incorporated into this AD by
reference? Actions required by this AD must be done in accordance
with Pilatus Service Bulletin No. 24-012, dated February 19, 1999,
and Pilatus Service Bulletin No. 24-014, dated October 27, 1999.
(1) The Director of the Federal Register approved this
incorporation by reference of Pilatus Service Bulletin No. 24-014,
dated October 27, 1999, under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) The Director of the Federal Register previously approved
incorporation by reference of Pilatus Service Bulletin No. 24-012,
dated February 19, 1999, as of October 4, 1999 (64 FR 45149, August
19, 1999).
(3) You can get copies from Pilatus Aircraft Ltd., Customer
Liaison Manager, CH-6371 Stans, Switzerland. You can look at copies
at the FAA, Central Region, Office of the Regional Counsel, 901
Locust, Room 506, Kansas City, Missouri, or at the Office of the
Federal Register, 800 North Capitol Street, NW, suite 700,
Washington, DC.
(i) When does this amendment become effective? This amendment
becomes effective on July 23, 2001.
Note 2: The subject of this AD is addressed in Swiss AD Numbers
HB 99-143, dated February 19, 1999, and HB 99-542, dated October 29,
1999.
Issued in Kansas City, Missouri, on May 22, 2001.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 01-13580 Filed 6-5-01; 8:45 am]
BILLING CODE 4910-13-P
Sources. Section 1 is written by AircraftDirectives from the record below and is a reading aid only. Section 2 is the United States Government's own text, reproduced without edit.
Federal Register: https://www.federalregister.gov/documents/2001/06/06/01-13580/airworthiness-directives-pilatus-aircraft-ltd-models-pc-12-and-pc-1245-airplanes
Official PDF: https://www.govinfo.gov/content/pkg/FR-2001-06-06/pdf/01-13580.pdf
Packet generated 2026-08-18 08:18 UTC.
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