[Federal Register Volume 69, Number 115 (Wednesday, June 16, 2004)]
[Rules and Regulations]
[Pages 33558-33561]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-13334]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2004-CE-08-AD; Amendment 39-13670; AD 2004-12-11]
RIN 2120-AA64


Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and 
PC-12/45 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA adopts a new airworthiness directive (AD) for all 
Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. 
This AD requires you to check the airplane logbook to determine whether 
certain inboard and outboard flap flexshafts have been replaced with 
parts of improved design. If the parts of improved design are not 
installed, you are required to replace certain inboard and/or outboard 
flap flexshafts with the parts of improved design. The pilot is allowed 
to do the logbook check. If the pilot can positively determine that the 
parts of improved design are installed, no further action is required. 
This AD is the result of mandatory continuing airworthiness information 
(MCAI) issued by the airworthiness authority for Switzerland. We are 
issuing this AD to prevent rupture of the flap flexshafts due to 
corrosion, which could cause the flap system to become inoperable.

DATES: This AD becomes effective on July 26, 2004.
    As of July 26, 2004, the Director of the Federal Register approved 
the incorporation by reference of certain publications listed in the 
regulation.

ADDRESSES: You may get the service information identified in this AD 
from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
Switzerland; telephone: +41 41 619 6208; facsimile: +41 41 619 7311; e-
mail: aircraft.com">SupportPC12@pilaltus-aircraft.com 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 view the AD docket at FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2004-CE-08-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. 
to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer,

[[Page 33559]]

FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, 
Missouri 64106; telephone: (816) 329-4059; facsimile: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Discussion

    What events have caused this AD? The Federal Office for Civil 
Aviation (FOCA), which is the airworthiness authority for Switzerland, 
recently notified FAA that an unsafe condition may exist on all Pilatus 
Models PC-12 and PC-12/45 airplanes equipped with an inboard and/or 
outboard flap flexshaft, part numbers (P/N) 945.02.02.203 and/or 
945.02.02.204. The FOCA reports several occurrences of corrosion found 
on the inner drive cables of these flap flexshafts.
    The FOCA determined that moisture from the pressurized cabin could 
enter the flap flexshafts through the fittings of the protection hose 
causing corrosion. This corrosion could cause the flap flexshafts to 
rupture.
    What is the potential impact if FAA took no action? If not 
prevented, corrosion on the flap flexshafts could cause flap flexshafts 
to rupture and lead to the flap system becoming inoperable.
    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 all Pilatus Models PC-12 and PC-12/45 
airplanes of the same type design that are equipped with an inboard 
and/or outboard flap flexshaft, P/N 945.02.02.203 and/or P/N 
945.02.02.204. This proposal was published in the Federal Register as a 
notice of proposed rulemaking (NPRM) on April 9, 2004 (69 FR 18843). 
The NPRM proposed to require you to check the airplane logbook to 
determine whether certain inboard and outboard flap flexshafts have 
been replaced with parts of improved design. If the parts of improved 
design are not installed, you would be required to replace certain 
inboard and/or outboard flap flexshafts with the parts of improved 
design.

Comments

    Was the public invited to comment? We provided the public the 
opportunity to participate in developing this AD. The following 
presents the comments received on the proposal and FAA's response to 
each comment:

Comment Issue No. 1: Revise the Stated Result of the Unsafe Condition

    What is the commenter's concern? The manufacturer states that 
failure of the flap system will not lead to loss of control of the 
airplane. The manufacturer explains that the flap computer (FCWU) 
protects the system against asymmetric flap deployment with a failure 
rate of 10E-9 in the event of a flexshaft rupture (and other failure 
modes). The pilot has no possibility to override this protection.
    The manufacturer wants us to state that rupture of the flap 
flexshafts due to corrosion could cause the flap system to become 
inoperative but does not result in loss of control of the airplane.
    What is FAA's response to the concern? We agree with the 
manufacturer. After reviewing additional information provided by the 
FOCA of Switzerland about the result of the unsafe condition on the 
flap flexshafts, we will change the final rule AD action based on this 
comment.

Comment Issue No. 2: Change the Costs of Compliance Section

    What is the commenter's concern? The manufacturer states that of 
the 260 airplanes affected by this AD, only 65 need to have the 
replacement parts installed. The manufacturer wants the cost of 
compliance changed to reflect the cost of installing the replacement 
parts for these 65 airplanes instead of all 260 airplanes.
    The manufacturer has also agreed to cover the cost of replacement 
parts for all airplanes even though the warranty credit period has 
expired. The manufacturer also wants us to change the cost of 
compliance to reflect this reduction.
    What is FAA's response to the concern? We partially agree with the 
manufacturer. We agree that there may be only 65 airplanes currently on 
the United States (U.S.) registry that need to have the replacements 
parts installed. However, because parts could have been replaced on an 
airplane after it left the manufacturer, we used the total number of 
affected airplanes in the Costs of Compliance section. We have no way 
of determining the exact number of airplanes that will need to have the 
replacements done.
    We are not changing the final rule AD action based on this comment. 
We are, however, adding a section to cover the cost for doing the 
logbook check. Since all of the affected airplanes will probably not 
need to have the replacement parts installed, a logbook check will have 
to be done on all of the affected airplanes in order to make this 
determination.

Comment Issue No. 3: Change Paragraph (e)(5)

    What is the commenter's concern? The manufacturer states that the 
language in paragraph (e)(5) prohibits you from ever installing any 
version of the inboard and outboard flap flexshafts other than part 
numbers (P/N) 945.02.02.205 and 945.02.02.206. Therefore, airplanes 
manufactured in the future with a new design part number for the flap 
flexshafts will be in automatic non-compliance with this AD.
    The manufacturer wants this language changed to prohibit ever 
installing P/Ns 945.02.02.203 and 945.02.02.204 but allows you to 
install new flap flexshafts introduced in the future.
    What is FAA's response to the concern? We agree with the commenter. 
Preventing future installations of new design parts was not the intent 
of this AD.
    We will change the final rule AD action based on this comment.

Comment Issue No. 4: Withdraw the Proposed AD Action To Mandate 
Compliance With Pilatus PC12 Service Bulletin No. 27-015

    What is the commenter's concern? The manufacturer states that there 
is no unsafe condition. The manufacturer further explains that the flap 
computer (FCWC) protects the system against asymmetric flap deployment 
with a failure rate of 10E-9 in the event of a flexshaft rupture (and 
other failure modes). This failure does not result in loss of control 
of the airplane and the pilot has no possibility to override this 
protection.
    The manufacturer also states that they can confirm that over 90 
percent of the U.S. registered airplanes have already had the 
replacement parts installed.
    The manufacturer wants the proposed AD action withdrawn.
    What is FAA's response to the concern? We do not agree that there 
is no unsafe condition. We agree that approximately 90 percent of the 
affected airplanes may have already had the replacement parts 
installed. However, at least 10 percent of the affected airplanes still 
need the replacement done. In addition, the only way to legally prevent 
these unsafe parts from being installed in the future is through AD 
action. This would include airplanes brought into the U.S. and put on 
the U.S. registry.
    Therefore, to ensure that all affected airplanes do not have the 
unsafe parts installed, we are not changing the final rule AD action 
based on this comment.

Comment Issue No. 5: Make the AD Serial Number Specific

    What is the commenter's concern? The commenter states that the 
manufacturer has been incorporating the new P/Ns in the production line 
of new airplanes since 2003 making the

[[Page 33560]]

inclusion of airplanes produced after Manufacturer Serial Number (MSN) 
489 illogical. Making the AD serial number specific speeds compliance 
and makes everyone's life easier.
    The commenter wants the AD changed to be serial number specific as 
specified in Pilatus PC12 Service Bulletin No. 27-015.
    What is FAA's response to the concern? We partially agree with the 
commenter. We agree that serial number specific ADs are easier to 
track; however, parts could be swapped from one of the earlier affected 
models and installed on a MSN outside of the range specified in the 
service information. To safeguard against this, we included a logbook 
check of all airplanes prior to doing any replacements.
    We are not changing the final rule AD action based on this comment.
    What is FAA's final determination on this issue? We have carefully 
reviewed the available data and determined that air safety and the 
public interest require adopting the AD as proposed except for the 
changes noted above and minor editorial corrections. We have determined 
that these changes:

--Are consistent with the intent that was proposed in the NPRM for 
correcting the unsafe condition; and
--Do not add any additional burden upon the public than was already 
proposed in the NPRM.

Changes to 14 CFR Part 39--Effect on the AD

    How does the revision to 14 CFR part 39 affect this AD? On July 10, 
2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, 
July 22, 2002), which governs the FAA's AD system. This regulation now 
includes material that relates to altered products, special flight 
permits, and alternative methods of compliance. This material 
previously was included in each individual AD. Since this material is 
included in 14 CFR part 39, we will not include it in future AD 
actions.

Costs of Compliance

    How many airplanes does this AD impact? We estimate that this AD 
affects 260 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 accomplish the 
logbook check:

----------------------------------------------------------------------------------------------------------------
                                                                Total cost per
             Labor cost                      Parts cost            airplane        Total cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
1 workhour x $65 per hour = $65.....  Not applicable.........              $65   $65 x 260 = $16,900.
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    We estimate the following costs to accomplish the replacement:

----------------------------------------------------------------------------------------------------------------
                                         Parts cost per flap                                Total cost on U.S.
    Labor cost per flap flexshaft             flexshaft         Total cost per airplane         operators
----------------------------------------------------------------------------------------------------------------
2 workhours per flap flexshaft (4      Parts covered under      $130 x 4 flap            Maximum cost for
 flap flexshafts per airplane) x $65    warranty by the          flexshafts = $520 to     replacing all 4 flap
 per hour = $130 per flap flexshaft.    manufacturer.            replace all 4 flap       flexshafts on all 260
                                                                 flexshafts.              airplanes = $520 x 260
                                                                                          = $135,200.
----------------------------------------------------------------------------------------------------------------

Compliance Time of This AD

    What is the compliance time of this AD? The compliance time for the 
replacement that will be required by this AD is ``within the next 30 
days after the effective date of this AD.''
    Why is this compliance time presented in calendar time instead of 
hours TIS? The unsafe condition specified by this AD is caused by 
corrosion. Corrosion can occur regardless of whether the airplane is in 
operation or is in storage. Therefore, to assure that the unsafe 
condition specified in this AD does not go undetected for a long period 
of time, a compliance time of calendar time is utilized.

Regulatory Findings

    Will this AD impact various entities? We have determined that this 
AD will not have federalism implications under Executive Order 13132. 
This AD 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.
    Will this AD involve a significant rule or regulatory action? For 
the reasons discussed above, I certify that this AD:
    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. 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.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2004-CE-08-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
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

0
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]

0
2. FAA amends Sec.  39.13 by adding a new AD to read as follows:

2004-12-11 Pilatus Aircraft Ltd.: Amendment 39-13670; Docket No. 
2004-CE-08-AD.

When Does This AD Become Effective?

    (a) This AD becomes effective on July 26, 2004.

What Other ADs Are Affected by This Action?

    (b) None.

[[Page 33561]]

What Airplanes Are Affected by This AD?

    (c) This AD affects Model PC-12 and PC-12/45 airplanes, all 
serial numbers, that are:
    (1) equipped with an inboard and/or outboard flap flexshaft, 
part number (P/N) 945.02.02.203 and/or P/N 945.02.02.204; and
    (2) certificated in any category.

What Is the Unsafe Condition Presented in This AD?

    (d) This AD is the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for 
Switzerland. The actions specified in this AD are intended to 
prevent rupture of the flap flexshafts due to corrosion, which could 
cause the flap system to become inoperable.

What Must I Do To Address This Problem?

    (e) To address this problem, you must do the following. If you 
already replaced both the inboard and outboard flap flexshafts, P/N 
945.02.02.203 and P/N 945.02.02.204, following Pilatus PC12 Service 
Bulletin No. 27-015, dated June 4, 2003, then paragraph (e)(5) of 
this AD is the only paragraph that applies to you:

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) For affected airplanes    Within the next 30    The owner/operator
 with a manufacturer serial    days after July 26,   holding at least a
 number (MSN) of 489 or        2004 (the effective   private pilot
 lower: check the airplane     date of this AD).     certificate as
 logbook to determine if P/N                         authorized by
 945.02.02.203 and P/N                               section 43.7 of the
 945.02.02.204 inboard and                           Federal Aviation
 outboard flap flexshafts                            Regulations (14 CFR
 are installed.                                      43.7) may perform
                                                     this check.
(2) For affected airplanes    Within the next 30    The owner/operator
 with a MSN of 490 and         days after July 26,   holding at least a
 above: check the airplane     2004 (the effective   private pilot
 logbook to ensure that P/N    date of this AD).     certificate as
 945.02.02.203 and P/N                               authorized by
 945.02.02.204 inboard and                           section 43.7 of the
 outboard flap flexshafts                            Federal Aviation
 have not been installed                             Regulations (14 CFR
 since delivery.                                     43.7) may perform
                                                     this check.
(3) If you can positively     Not Applicable......  Not applicable.
 determine that both P/Ns
 945.02.02.203 and
 945.02.02.204 inboard and
 outboard flap flexshafts
 are not installed, then no
 replacement is required.
(4) If you cannot positively  Before further        Follow Pilatus PC12
 determine that both P/Ns      flight after the      Service Bulletin
 945.02.02.203 and             logbook checks        No. 27-015 as
 945.02.02.204, inboard and    required in           specified in
 outboard flap flexshafts      paragraph (e)(1)      paragraph (f) of
 are not installed, then you   and (e)(2) of this    this AD.
 must replace each one or      AD.
 both with P/N 945.02.02.205
 and P/N 945.02.02.206, as
 applicable (or a later FAA-
 approved manufactured part
 of improved design).
(5) Do not install inboard    As of July 26, 2004   Not applicable.
 and outboard flap             (the effective date
 flexshafts, P/Ns              of this AD).
 945.02.02.203 and
 945.02.02.204.
------------------------------------------------------------------------

What Revision Levels Do the Affected Service Bulletin Incorporate?

    (f) The service bulletin required to do the actions required in 
this AD incorporates the following pages:

------------------------------------------------------------------------
         Affected pages             Revision level           Date
------------------------------------------------------------------------
1 and 2.........................  A.................  November 13, 2003.
3 through 11....................  Original Issue....  June 4, 2003.
------------------------------------------------------------------------

May I Request an Alternative Method of Compliance?

    (g) You may request a different method of compliance or a 
different compliance time for this AD by following the procedures in 
14 CFR 39.19. Unless FAA authorizes otherwise, send your request to 
your principal inspector. The principal inspector may add comments 
and will send your request to the Manager, Standards Office, Small 
Airplane Directorate, FAA. For information on 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.

Does This AD Incorporate Any Material by Reference?

    (h) You must do the actions required by this AD following the 
instructions in Pilatus PC12 Service Bulletin No. 27-015, pages 1 
and 2, Revision A, dated November 13, 2003, pages 3 through 11, 
Original issue, dated June 4, 2003. The Director of the Federal 
Register approved the incorporation by reference of this service 
bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You 
may get a copy from Pilatus Aircraft Ltd., Customer Liaison Manager, 
CH-6371 Stans, Switzerland; telephone: +41 41 619 6208; facsimile: 
+41 41 619 7311; e-mail: aircraft.com">SupportPC12@pilaltus-aircraft.com 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 review copies at FAA, Central 
Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas 
City, Missouri 64106; or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Is There Other Information That Relates to This Subject?

    (i) Swiss AD Number HB-2004-068, dated March 4, 2004, also 
addresses the subject of this AD.

    Issued in Kansas City, Missouri, on June 3, 2004.
Dorenda D. Baker,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 04-13334 Filed 6-15-04; 8:45 am]
BILLING CODE 4910-13-P