[Federal Register Volume 71, Number 30 (Tuesday, February 14, 2006)]
[Proposed Rules]
[Pages 7698-7701]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-2020]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-19220; Directorate Identifier 2004-CE-27-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 
airplanes equipped with certain crew seat bucket assemblies with and 
without a backrest recline system. This proposed AD would require you 
to replace the backrest tubes on these crew seat bucket assemblies at a 
specified time and adds a life limit for these backrest tubes. This 
proposed AD results from mandatory continuing airworthiness information 
(MCAI) issued by the airworthiness authority for Switzerland. We are 
issuing this proposed AD to prevent cracks in the backrest tubes of 
certain crew seat bucket assemblies, which could result in failure of 
the seat system. This failure could lead to the pilot and co-pilot's 
reduced ability to control the airplane. This failure could also affect 
the proper function of the seat restrain system in the case of an 
emergency landing.

DATES: We must receive comments on this proposed AD by March 16, 2006.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD:

[[Page 7699]]

     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
     Fax: 1-202-493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Pilatus Aircraft Ltd., Customer Support Manager, CH-6371 
Stans, Switzerland; telephone: +41 41 619 6208; facsimile: +41 41 619 
7311; or Pilatus Business Aircraft Ltd., Product Support Department, 
11755 Airport Way, Broomfield, Colorado 80021; telephone: (303) 465-
9099; facsimile: (303) 465-6040 for the service information identified 
in this proposed AD.
    You may examine the comments on this proposed AD in the AD docket 
on the Internet at http://dms.dot.gov.

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? We invite you to send any 
written relevant data, views, or arguments regarding this proposal. 
Send your comments to an address listed under ADDRESSES. Include the 
docket number, ``FAA-2004-19220; Directorate Identifier 2004-CE-27-AD'' 
at the beginning of your comments. We specifically invite comments on 
the overall regulatory, economic, environmental, and energy aspects of 
the proposed AD. We will consider all comments received by the closing 
date and may amend the proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed rulemaking. Using the search 
function of the DOT docket Web site, anyone can find and read the 
comments received into any of our dockets, including the name of the 
individual who sent the comment (or signed the comment on behalf of an 
association, business, labor union, etc.). You may review the DOT's 
complete Privacy Act Statement in the Federal Register published on 
April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the Dockets

    Where can I go to view the docket information? You may examine the 
docket that contains the proposal, any comments received and any final 
disposition on the Internet at http://dms.dot.gov, or in person at the 
DOT Docket Offices between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Office (telephone 1-800-647-5227) 
is located on the plaza level of the Department of Transportation 
Nassif Building at the street address stated in ADDRESSES. Comments 
will be available in the AD docket shortly after the Docket Management 
Facility receives them.

Discussion

    What events have caused this proposed AD? The Federal Office for 
Civil Aviation (FOCA), which is the airworthiness authority for 
Switzerland, notified FAA that an unsafe condition may exist on all 
Pilatus Models PC-12 and PC-12/45 airplanes equipped with certain crew 
seat bucket assemblies with and without a backrest recline system. The 
FOCA reports that during a regular maintenance inspection, the seat 
bucket assembly tubes on a crew seat with a recline system had failed.
    Fatigue on the left-hand (LH) and right-hand (RH) seat bucket 
assembly tubes at the location of the energy device pins caused the 
seat bucket assembly tubes to fail. The lower tubes were attached but 
the upper tubes were completely detached.
    Pilatus conducted further investigation to determine if additional 
crew seat bucket assembly backrest tubes have fatigue cracks.
    Thirty-one of the affected airplanes were inspected. Six pilot and 
two co-pilot seats were found with partial fatigue cracks. None had 
completely failed. The cracks were found on the backrest tubes of the 
crew seat bucket assemblies with the recline feature.
    The result of the inspections led to the establishment of a life 
limit for the backrest tubes on certain crew seat bucket assemblies 
with and without a backrest recline system.
    What is the potential impact if FAA took no action? If not 
prevented, cracks in the backrest tubes of the seat bucket assembly 
could cause the seat system to fail. This failure could lead to the 
pilot and co-pilot's reduced ability to control the airplane. This 
failure could also affect the proper function of the seat system in the 
case of an emergency landing.
    Is there service information that applies to this subject? Pilatus 
has issued Pilatus PC12 Maintenance Manual Temporary Revision No. 04-
13, dated June 15, 2005.
    What are the provisions of this service information? The 
maintenance manual temporary revision establishes a life limit for the 
backrest tubes on crew seat bucket assemblies with and without a 
recline system.
    What action did the FOCA take? The FOCA classified this maintenance 
manual temporary revision as mandatory and issued Swiss AD Number HB-
2005-470, Effective Date: December 30, 2005, to ensure the continued 
airworthiness of these airplanes in Switzerland.
    Did the FOCA inform the United States under the bilateral 
airworthiness agreement? These Pilatus Models PC-12 and PC-12/45 
airplanes 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.
    Under this bilateral airworthiness agreement, the FOCA has kept us 
informed of the situation described above.

FAA's Determination and Requirements of This Proposed AD

    What has FAA decided? We have examined the FOCA's findings, 
reviewed all available information, and determined that AD action is 
necessary for products of this type design that are certificated for 
operation in the United States.
    Since the unsafe condition described previously is likely to exist 
or develop on other Pilatus Models PC-12 and PC-12/45 airplanes of the 
same type design that are registered in the United States, we are 
proposing AD action to prevent cracks in the backrest tubes of certain 
crew seat bucket assemblies, which could result in failure of the seat 
system. This failure could lead to the pilot and co-pilot's reduced 
ability to control the airplane. This failure could also affect the 
proper function of the seat restrain system in the case of an emergency 
landing.

FAA's Determination and Requirements of the Proposed AD

    Why have we determined AD action is necessary and what would this

[[Page 7700]]

proposed AD require? We are proposing this AD to address an unsafe 
condition that we determined is likely to exist or develop on other 
products of this same type design. The proposed AD would require you to 
replace the backrest tubes on certain crew seat bucket assemblies at a 
specified time and adds a life limit for the backrest tubes.

Costs of Compliance

    How many airplanes would this proposed AD impact? We estimate that 
this proposed AD affects 260 airplanes in the U.S. registry.
    What would be the cost impact of this proposed AD on owners/
operators of the affected airplanes? We estimate the following costs to 
accomplish this proposed replacement:

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                                                                  Total cost per seat       Total cost on U.S.
              Labor cost                      Parts cost            bucket  assembly            operators
----------------------------------------------------------------------------------------------------------------
3 work hours x $65 per hour = $195     $600 per seat bucket     $195 + $600 = $795 per   $795 per seat bucket
 per seat bucket assembly.              assembly. 2 seats on     seat bucket assembly.    assembly x 2 per
                                        each airplane.                                    airplane = $1,590.
                                                                                         $1,590 x 260 =
                                                                                          $413,400.
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Authority for This Rulemaking

    What authority does FAA have for issuing this rulemaking action? 
Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    Would this proposed AD impact various entities? We have determined 
that this proposed AD would not have federalism implications under 
Executive Order 13132. This proposed AD 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.
    For the reasons discussed above, I certify that the proposed 
regulation:
    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 regulatory evaluation of the estimated costs to 
comply with this proposed AD. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

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 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. The Federal Aviation Administrator amends Sec.  39.13 by adding 
the following new airworthiness directive (AD):

Pilatus Aircraft LTD.: Docket No. FAA-2004-19220; Directorate 
Identifier 2004-CE-27-AD.

When Is the Last Date I Can Submit Comments on This Proposed AD?

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this proposed AD action by March 16, 2006.

What Other ADs Are Affected by This Action?

    (b) None.

What Airplanes Are Affected by This AD?

    (c) This AD affects all Models PC-12 and PC-12/45 airplanes that 
are equipped with the following crew seat bucket assemblies and are 
certificated in any category:
    (1) Crew seats with a recline system, part numbers (P/N): 
959.30.01.111, 959.30.01.112, 959.30.01.121, and 959.30.01.122.
    (2) Crew seats without recline system, P/Ns: 959.30.01.131, 
959.30.01.132, 959.30.01.133, and 959.30.01.134.

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 cracks in the backrest tubes of certain crew seat bucket 
assemblies, which could result in failure of the seat system. This 
failure could lead to the pilot and co-pilot's reduced ability to 
control the airplane. This failure could also affect the proper 
function of the seat restrain system in the case of an emergency 
landing.

What Must I Do To Address This Problem?

    (e) To address this problem, you must do the following:

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
------------------------------------------------------------------------
(1) For crew seat bucket      Initially replace     As specified in
 assemblies with a recline     upon the              Pilatus PC12
 system, part numbers (P/N)    accumulation of       Maintenance Manual
 959.30.01.111,                5,000 hours time-in-  Temporary Revision
 959.30.01.112,                service (TIS) or      No. 04-13, dated
 959.30.01.121, and            within the next 100   June 15, 2005.
 959.30.01.122 (or FAA-        hours TIS after the   Replace following
 approved equivalent P/Ns),    effective date of     the procedures in
 replace the backrest tubes.   this AD, whichever    the applicable
                               occurs later.         component
                               Thereafter, replace   maintenance manual.
                               the backrest tubes    (CMM)
                               upon the
                               accumulation of
                               5,000 hours TIS
                               (the life limit
                               established in this
                               AD).

[[Page 7701]]

 
(2) For crew seat bucket      Initially replace     As specified in
 assemblies without a          upon the              Pilatus PC12
 recline system, P/Ns          accumulation of       Maintenance Manual
 959.30.01.131,                10,000 hours TIS or   Temporary Revision
 959.30.01.132,                within the next 100   No. 04-13, dated
 959.30.01.133, and            hours TIS after the   June 15, 2005.
 959.30.01.134 (or FAA-        effective date of     Replace following
 approved equivalent P/Ns),    this AD, whichever    the procedures in
 replace the backrest tubes.   occurs later.         the CMM.
                               Thereafter, replace
                               the backrest tubes
                               upon the
                               accumulation of
                               10,000 hours TIS
                               (the life limit
                               established in this
                               AD).
(3) Do not install:
    (i) Any crew seat bucket  As of the effective   Not Applicable.
     assembly with a recline   date of this AD.
     system, P/N               The life limits
     959.30.01.111,            specified in
     959.30.01.112,            paragraphs (e)(1)
     959.30.01.121, and        and (e)(2) of this
     959.30.01.122 (or FAA-    AD apply to all
     approved equivalent P/    parts installed as
     Ns), with unknown hours   spares.
     TIS or which has
     accumulated 5,000 or
     more hours TIS; or
    (ii) Any crew seat
     bucket assembly without
     a recline system, P/N
     959.30.01.131,
     959.30.01.132,
     959.30.01.133, and
     959.30.01.134 (or FAA-
     approved equivalent P/
     Ns), with unknown hours
     TIS or which has
     accumulated 10,000 or
     more hours TIS.
(4) 14 CFR 21.303 allows for  Not Applicable......  Not Applicable.
 replacement parts through
 parts manufacturer approval
 (PMA). The phrase ``or FAA-
 approved equivalent part
 number'' in this AD is
 intended to signify those
 parts that are PMA parts
 approved through
 identicality to the design
 of the part under the type
 certificate and replacement
 parts to correct the unsafe
 condition under PMA (other
 than identicality). If
 parts are installed that
 are identical to the unsafe
 parts, then the corrective
 actions of the AD affect
 these parts also. In
 addition, equivalent
 replacement parts to
 correct the unsafe
 condition under PMA (other
 than identicality) may also
 be installed provided they
 meet current airworthiness
 standards, which include
 those actions cited in this
 AD.
(5) You must contact the      As of the effective   Not Applicable.
 type certificate holder any   date of this AD.
 time a modification or
 repair is done that affects
 the parts listed in
 paragraphs (e)(1), (e)(2),
 and (e)(3) of this AD to
 determine the effect, if
 any, the modification or
 repair may have on the life
 limits established in this
 AD.
------------------------------------------------------------------------


    Note: Return all replaced backrest tubes to Pilatus Aircraft 
Ltd., Structural Analysis Group ECE, Ch-6371 Stans, Switzerland. 
Include the following information: crew seat P/N and serial number, 
aircraft manufacturer serial number, aircraft flying hours, number 
of flights, and replacement date of the replaced backrest tubes.

May I Request an Alternative Method of Compliance?

    (f) The Manager, Standards Office, Small Airplane Directorate, 
FAA, has the authority to approve alternative methods of compliance 
for this AD, if requested using the procedures found in 14 CFR 
39.19. For information on any already approved alternative methods 
of compliance or for information pertaining to this AD, 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.

Is There Other Information That Relates to This Subject?

    (g) Swiss AD Number HB-2005-470, Effective Date: December 30, 
2005, also addresses the subject of this AD.

May I Get Copies of the Documents Referenced in This AD?

    (h) To get copies of the documents referenced in this AD, 
contact Pilatus Aircraft Ltd., Customer Support Manager, CH-6371 
Stans, Switzerland; telephone: +41 41 619 6208; facsimile: +41 41 
619 7311; or Pilatus Business Aircraft Ltd., Product Support 
Department, 11755 Airport Way, Broomfield, Colorado 80021; 
telephone: (303) 465-9099; facsimile: (303) 465-6040. To view the AD 
docket, go to the Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-
401, Washington, DC, or on the Internet at http://dms.dot.gov. The 
docket number is Docket No. FAA-2004-19220; Directorate Identifier 
2004-CE-27-AD.

    Issued in Kansas City, Missouri, on February 7, 2006.
Steven W. Thompson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E6-2020 Filed 2-13-06; 8:45 am]
BILLING CODE 4910-13-P