[Federal Register Volume 66, Number 183 (Thursday, September 20, 2001)]
[Proposed Rules]
[Pages 48381-48384]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-23412]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 66, No. 183 / Thursday, September 20, 2001 / 
Proposed Rules  

[[Page 48381]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-CE-77-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).

-----------------------------------------------------------------------

SUMMARY: This document proposes to supersede Airworthiness Directive 
(AD) 99-19-32, which applies to certain Pilatus Aircraft Ltd. (Pilatus) 
Models PC-12 and PC-12/45 airplanes. AD 99-19-32 currently requires you 
to inspect the flap actuator internal gear system for correct end-play 
and backlash measurements and accomplish any corrective adjustments, as 
necessary. Pilatus has identified modifications for the flap system and 
designed and manufactured a new flap control and warning unit (FCWU) 
that permits the flap power drive-unit circuit breaker to close during 
flight. The proposed AD would require you to repetitively inspect all 
flap actuator internal gear systems to ensure correct end-play and 
backlash measurements with any necessary corrective adjustments, 
incorporate certain modifications to the flap system, and install a new 
design FCWU. The proposed AD would also require you to modify the flap 
control wiring and install a flap power drive-unit field control panel. 
The actions specified by the proposed AD are intended to allow the flap 
power drive-unit circuit breaker to close during flight and prevent 
current surges in the flap control system. Both conditions have the 
potential for flap system failure with consequent reduced or loss of 
control of the airplane.

DATES: The Federal Aviation Administration (FAA) must receive any 
comments on this proposed rule on or before October 26, 2001.

ADDRESSES: Submit comments to FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2000 CE-77-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. You may view comments at 
this location between 8 a.m. and 4 p.m., Monday through Friday, except 
Federal holidays.
    You may obtain service information that applies to the proposed AD 
from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 619 6224; 
or from Pilatus Business Aircraft Ltd., Product Support Department, 
11755 Airport Way, Broomfield, Colorado 80021; telephone: (303) 465-
9099; facsimile: (303) 465-6040. You may also view this information at 
the Rules Docket at the address above.

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:

Comments Invited

How Do I Comment on This Proposed AD?

    The FAA invites comments on this proposed rule. You may submit 
whatever written data, views, or arguments you choose. You need to 
include the rule's docket number and submit your comments to the 
address specified under the caption ADDRESSES. We will consider all 
comments received on or before the closing date. We may amend this 
proposed rule in light of comments received. Factual information that 
supports your ideas and suggestions is extremely helpful in evaluating 
the effectiveness of this proposed AD action and determining whether we 
need to take additional rulemaking action.

Are There Any Specific Portions of This Proposed AD I Should Pay 
Attention to?

    The FAA specifically invites comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed rule that 
might suggest a need to modify the rule. You may view all comments we 
receive before and after the closing date of the rule in the Rules 
Docket. We will file a report in the Rules Docket that summarizes each 
contact we have with the public that concerns the substantive parts of 
this proposed AD.

How Can I Be Sure FAA Receives My Comment?

    If you want FAA to acknowledge the receipt of your comments, you 
must include a self-addressed, stamped postcard. On the postcard, write 
``Comments to Docket No. 2000-CE-77-AD.'' We will date stamp and mail 
the postcard back to you.

Discussion

Has FAA Taken Any Action to This Point?

    Reports of excessive backlash in the flap actuators of the internal 
gear system on certain Pilatus Models PC-12 and PC-12/45 airplanes 
caused FAA to issue AD 99-19-32, Amendment 39-11319 (64 FR 50439, 
September 17, 1999).
    AD 99-19-32 currently requires you to inspect the flap actuator 
internal gear system for correct end-play and backlash measurements and 
accomplish any corrective adjustments, as necessary.

What Has Happened Since AD 99-19-32 To Initiate This Action?

    The Federal Office for Civil Aviation (FOCA), which is the 
airworthiness authority for Switzerland, recently notified FAA of the 
need to change AD 99-19-32. The FOCA reports that Pilatus has 
identified modifications for the flap system and designed and 
manufactured a new flap control and warning unit (FCWU) that permits 
the flap power drive-unit circuit breaker to close during flight.
    The previous FCWU does not allow the pilot to close the flap power 
drive-unit circuit breaker during flight and the FCWU cannot sense when 
a single actuator becomes worn. This could result in flap panel 
distortion. The incorporation of these modifications to the flap system 
and the installation of the new design FCWU, Pilatus part number FCWU 
99-3, make the current end-play and backlash measurement procedures 
incorrect.
    Pilatus has also identified quality deficiencies with serial 
numbers less than 100,001 of Pilatus part number FCWU 99-3.
    In addition, the FOCA reports that electrical surges in the flap 
system can decrease the electrical life of the flap

[[Page 48382]]

power drive-unit motor contactor. At the 40-degree flaps position, the 
flaps-down limit switch (S035) operates before the flap control warning 
unit can stop the extend command, which causes the flap power drive-
unit's Up/Down relay (K32) to change from the extend to the retract 
position. The current in the field winding then goes in the opposite 
direction while a current still flows to the motor. Electrical current 
to the flap power drive-unit motor and field windings remains when the 
circuit breaker (CB034) closes and the motor contactor (K31 or K670) 
stays closed.

Is There Service Information That Applies to This Subject?

    Pilatus has issued Service Bulletin No. 27-008, which incorporates 
the following pages:

----------------------------------------------------------------------------------------------------------------
            Effective pages                     Revision level                            Date
----------------------------------------------------------------------------------------------------------------
1, 2, and 11..........................  2.............................  September 13, 2000.
3 through 10 and 12 through 114.......  1.............................  June 26, 2000.
----------------------------------------------------------------------------------------------------------------

    Pilatus Service Bulletin No. 27-008 includes procedures for the 
following:
    --Installing the new design FCWU (Pilatus part number FCWU 99-3 
with a serial number of 100,001 or higher);
    --Installing flap position-indication resolvers at the center and 
inboard flap actuator positions;
    --Removing the flap position-indication resolvers from the outboard 
flap mechanism;
    --Modifying the applicable electrical cables and installing new 
cables as necessary;
    --Installing a remote controlled circuit breaker (RCCB) system;
    --Accomplishing the rigging procedure to set the four flap 
positions (0 degrees, 15 degrees, 30 degrees, and 40 degrees full 
flap);
    --Installing a bus link between CB601, CB034, CB035, CB415, and 
CB416;
    --Replacing the P12H4 wire with P12HO wire;
    --Changing the wiring for CB652 and CB653 at Frame 16; and
    --Changing the FCWU software specification from Rel. 3.10/R 1.14 to 
Rel. 3.11/R 1.14.
    Pilatus has also issued the following:
    --Service Bulletin No. 27-012, dated September 13, 2000, which 
specifies replacing any Pilatus part number PCWU 99-3, serial number of 
100,000 or less, with one that has a serial number of 100,001 or 
higher;
    --Pilatus PC-12 Maintenance Manual Temporary Revision No. 27-13, 
dated April 30, 2000, which includes updated procedures for inspecting 
the flap actuator internal gear system for correct end-play and 
backlash measurements with any necessary corrective adjustment; and
    --Service Bulletin No. 27-011, Revision No. 1, dated January 26, 
2001, which includes procedures for modifying the flap control wiring 
and installing a flap power drive-unit field control panel.

What Action Did FOCA Take?

    The FOCA classified the service information as mandatory and issued 
the following in order to ensure the continued airworthiness of these 
airplanes in Switzerland:
    --Swiss AD Number HB 2000-443, dated November 9, 2000;
    --Swiss AD Number HB 2000-444, dated November 9, 2000; and
    --Swiss AD Number HB 2001-070, dated February 12, 2001.

Was This in Accordance With the Bilateral Airworthiness Agreement?

    These airplane models are manufactured in Switzerland and are 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, the FOCA has 
kept FAA informed of the situation described above.

The FAA's Determination and an Explanation of the Provisions of the 
Proposed AD

What Has FAA Decided?

    The FAA has examined the findings of the FOCA; reviewed all 
available information, including the service information referenced 
above; and determined that:
    --The unsafe condition referenced in this document exists or could 
develop on other Pilatus PC-12 and PC-12/45 airplanes of the same type 
design;
    --The actions specified in the previously-referenced service 
information should be accomplished on the affected airplanes; and
    --AD action should be taken in order to correct this unsafe 
condition.

What Would the Proposed AD Require?

    The proposed AD would supersede AD 99-19-32 and would require you 
to accomplish the following in accordance with the previously 
referenced service information:
    --Repetitively inspect the flap actuator internal gear system for 
correct end-play and backlash measurements with any necessary 
corrective adjustments;
    --Incorporate certain modifications to the flap system and install 
a new design FCWU with a serial number of 100,001 or higher, or FAA-
approved equivalent part number; and
    --Modify the flap control wiring and install a flap power drive-
unit field control panel.

Cost Impact

How Many Airplanes Would the Proposed AD Impact?

    We estimate that the proposed AD affects 135 airplanes in the U.S. 
registry.

What Would Be the Cost Impact of the Proposed AD on Owners/Operators of 
the Affected Airplanes?

    We estimate the following costs to accomplish the proposed initial 
inspection of the flap actuator internal gear system for end-play and 
backlash measurements. We have no way of determining the number of 
corrective adjustments each owner/operator of the affected airplanes 
would need to accomplish, the nature of such adjustments, or the number 
of repetitive inspections each owner/operator would incur. Therefore, 
the cost estimate only takes into account the cost of the proposed 
initial inspection:

----------------------------------------------------------------------------------------------------------------
                                                                               Total cost per     Total cost on
                Labor cost                             Parts cost                 airplane       U.S. operators
----------------------------------------------------------------------------------------------------------------
6 workhours X $60 per hour = $360........  Not applicable...................              $360           $48,600
----------------------------------------------------------------------------------------------------------------


[[Page 48383]]

    We estimate the following costs to incorporate certain 
modifications to the flap system and install a new design FCWU with a 
serial number of 100,001 or higher:

----------------------------------------------------------------------------------------------------------------
                                                                               Total cost per     Total cost on
                Labor cost                             Parts cost                 airplane       U.S. operators
----------------------------------------------------------------------------------------------------------------
70 workhours X $60 per hour = $4,200.....  Pilatus will provide parts at no             $4,200          $567,000
                                            cost to the owner/operator.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to modify the flap control wiring 
and install a flap power drive-unit field control panel:

----------------------------------------------------------------------------------------------------------------
                                                                               Total cost per     Total cost on
                Labor cost                             Parts cost                 airplane       U.S. operators
----------------------------------------------------------------------------------------------------------------
5 workhours X $60 per hour = $300........  Pilatus will provide parts at no               $300           $40,500
                                            cost to the owner/operator.
----------------------------------------------------------------------------------------------------------------

Regulatory Impact

Would This Proposed AD Impact Various Entities?

    The regulations proposed herein would 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 proposed rule would not have federalism 
implications under Executive Order 13132.

Would This Proposed AD Involve a Significant Rule or Regulatory Action?

    For the reasons discussed above, I certify that this proposed 
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, under 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. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. FAA amends Sec. 39.13 by removing Airworthiness Directive (AD) 
99-19-32, Amendment 39-11319 (64 FR 50439, September 17, 1999), and 
adding a new AD to read as follows:

Pilatus Aircraft Ltd.: Docket No. 2000-CE-77-AD; Supersedes AD 99-
19-32, Amendment 39-11319.

    (a) What airplanes are affected by this AD? This AD affects 
Models PC-12 and PC-12/45 airplanes, all serial numbers, that are 
certificated in any category. Carefully check paragraphs (d)(1) 
through (d)(6) of this AD for the specific actions that apply to 
each airplane. All airplanes will be affected by multiple actions 
specified in these paragraphs.
    (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 
the AD are intended to allow the flap power drive-unit circuit 
breaker to close during flight and prevent current surges in the 
flap control system. If the pilot cannot close the circuit breaker 
during flight, the flight control and warning unit (FCWU) would not 
sense a worn actuator. Current surges in the flap control system 
could decrease the electrical life of the flap power drive-unit 
motor contactor. Both conditions have the potential for flap system 
failure with consequent reduced or loss of control of the airplane.
    (d) What actions must I accomplish to address this problem? To 
address this problem, you must accomplish the following:

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) For airplanes that        Within the next 50    In accordance with
 incorporate a manufacturer    hours time-in-        the Accomplishment
 serial number (MSN) in the    service (TIS) after   Instructions
 range of 101 through 320,     the effective date    section of Pilatus
 accomplish the following:     of this AD, unless    Service Bulletin
 (i) Do the modifications      already               No. 27-008, pages
 and installations to the      accomplished.         1, 2, and 11 at the
 flap system, as specified                           Revision 2 level,
 in the service information.                         dated September 13,
 (ii) Install a new design                           2000; and pages 3
 flap control and warning                            through 10 and 12
 unit (FCWU) (Pilatus part                           through 114 at the
 number FCWU 99-3) with a                            Revision 1 level,
 serial number of 100,001 or                         dated June 26,
 higher, or FAA-approved                             2000. Pilatus
 equivalent part number.                             Service Bulletin 27-
                                                     012, dated
                                                     September 13, 2000,
                                                     also relates to
                                                     this subject.
------------------------------------------------------------------------

[[Page 48384]]

 
(2) If you accomplished the   Within the next 50    In accordance with
 modifications required by     hours TIS after the   the Accomplishment
 paragraph (d)(1) of this AD   effective date of     Instructions
 in accordance with Pilatus    this AD, unless       section of Pilatus
 Service Bulletin 27-008,      already               Service Bulletin
 all pages at the Revision 1   accomplished.         No. 27-008, pages
 level, dated June 26, 2000,                         1, 2, and 11 at the
 you only have to install a                          Revision 2 level,
 new design FCWU (Pilatus                            dated September 13,
 part number FCWU 99-3) with                         2000; and pages 3
 a serial number of 100,001                          through 10 and 12
 or higher, or FAA-approved                          through 114 at the
 equivalent part number.                             Revision 1 level,
                                                     dated June 26,
                                                     2000. Pilatus
                                                     Service Bulletin 27-
                                                     012, dated
                                                     September 13, 2000,
                                                     also relates to
                                                     this subject.
------------------------------------------------------------------------
(3) For airplanes that        Within the next 50    In accordance with
 incorporate an MSN in the     hours TIS after the   the Accomplishment
 range of 321 through 331,     effective date of     Instructions
 333, 335, 336, 338 through    this AD, unless       section of Pilatus
 341, 343, or 345, install a   already               Service Bulletin
 new design FCWU (Pilatus      accomplished.         No. 27-008, pages
 part number FCWU 99-3) with                         1, 2, and 11 at the
 a serial number of 100,001                          Revision 2 level,
 or higher, or FAA-approved                          dated September 13,
 equivalent part number.                             2000; and pages 3
                                                     through 10 and 12
                                                     through 114 at the
                                                     Revision 1 level,
                                                     dated June 26,
                                                     2000. Pilatus
                                                     Service Bulletin 27-
                                                     012, dated
                                                     September 13, 2000,
                                                     also relates to
                                                     this subject.
------------------------------------------------------------------------
(4) For airplanes that        Within the next 50    In accordance with
 incorporate an MSN in the     hours TIS after the   the Accomplishment
 range of 101 through 400,     effective date of     Instructions
 modify the flap control       this AD.              section of Pilatus
 wiring and install a flap                           Service Bulletin
 power drive-unit field                              No. 27-011,
 control panel.                                      Revision No. 1,
                                                     dated January 26,
                                                     2001.
------------------------------------------------------------------------
(5) For all MSN airplanes,    Inspect initially     In accordance with
 inspect the flap actuator     within the next 50    the instruction in
 internal gear system for      hours TIS after the   Pilatus PC-12
 correct end-play and          effective date of     Maintenance Manual
 backlash measurements and     this AD and           Temporary Revision
 make any necessary            thereafter at         No. 27-13, dated
 corrective adjustments.       intervals not to      April 30, 2000.
                               exceed 100 hours
                               TIS. Accomplish
                               corrective
                               adjustments prior
                               to further flight
                               after the
                               inspection where
                               deficiencies are
                               detected.
------------------------------------------------------------------------
(6) For all MSN airplanes,    As of the effective   Not Applicable.
 do not install any Pilatus    date of this AD.
 part number FCWU 99-3 that
 has a serial number of
 100,000 or less.
------------------------------------------------------------------------


    Note 1: The FAA recommends that you incorporate the most up-to-
date Pilatus reports and revisions pertaining to this subject into 
the Pilatus PC-12 Pilot's Operating Handbook. The most up-to-date 
documents as of the issue date of this AD are Temporary Revision No. 
15, Report No. 01973-001, Issued: April 3, 2000, Sections 3 and 7; 
and Temporary Revision No. 32, Report No. 01973-001, Issued: January 
8, 2001, Sections 2 and 3.

    (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.

    Note 2: 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) How do I get copies of the documents referenced in this AD? 
You may obtain copies of the documents referenced in this AD from 
Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
Switzerland; or from Pilatus Business Aircraft Ltd., Product Support 
Department, 11755 Airport Way, Broomfield, Colorado 80021. You may 
examine these documents at FAA, Central Region, Office of the 
Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.
    (i) Does this amendment affect any other regulation? This 
amendment supersedes AD 99-19-32, Amendment 39-11319.

    Note 3: The subject of this AD is addressed in Swiss AD Number 
HB 2000-443, dated November 9, 2000; Swiss AD Number HB 2000-444, 
dated November 9, 2000; and Swiss AD Number HB 2001-070, dated 
February 12, 2001.


    Issued in Kansas City, Missouri, on September 10, 2001.
Michael K. Dahl,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-23412 Filed 9-19-01; 8:45 am]
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