[Federal Register Volume 72, Number 210 (Wednesday, October 31, 2007)]
[Proposed Rules]
[Pages 61580-61582]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-21421]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0116; Directorate Identifier 2007-CE-082-AD]
RIN 2120-AA64


Airworthiness Directives; PILATUS AIRCRAFT LTD. Model PC-12, PC-
12/45, and PC-12/47 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. This proposed AD results from mandatory 
continuing airworthiness information (MCAI) originated by an aviation 
authority of another country to identify and correct an unsafe 
condition on an aviation product. The MCAI describes the unsafe 
condition as:

    It has been found that some of the above mentioned MLG special 
bolts can be defective. The problem is only applicable to specific 
bolts with serial numbers that start with the letters AT or have the 
supplier code AT. Investigations revealed that there is a 
possibility for hydrogen embrittlement which occurs during the 
manufacture process.
    Components in this condition can decrease the specific fatigue 
life and could lead to MLG collapse during operation with consequent 
loss of airplane control.

The proposed AD would require actions that are intended to address the 
unsafe condition described in the MCAI.

DATES: We must receive comments on this proposed AD by November 30, 
2007.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone (800) 647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Doug Rudolph, Aerospace Engineer, FAA, 
Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri 
64106; telephone: (816) 329-4059; fax: (816) 329-4090.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2007-0116; 
Directorate Identifier 2007-CE-082-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    The Federal Office of Civil Aviation (FOCA), which is the aviation 
authority for Switzerland, has issued FOCA AD HB-2007-382, dated August 
27, 2007 (referred to after this as ``the MCAI''), to correct an unsafe 
condition for the specified products. The MCAI states:

    It has been found that some of the above mentioned MLG special 
bolts can be defective. The problem is only applicable to specific 
bolts with serial numbers that start with the letters AT or have the 
supplier code AT. Investigations revealed that there is a 
possibility for hydrogen embrittlement which occurs during the 
manufacture process.
    Components in this condition can decrease the specific fatigue 
life and could lead to MLG collapse during operation with consequent 
loss of airplane control.

    In order to correct the situation, this AD requires the 
identification of all MLG special bolts to determine if the bolts 
have serial numbers that start with the letters AT or have the 
supplier code AT and the replacement of affected special bolts.

    You may obtain further information by examining the MCAI in the AD 
docket.

Relevant Service Information

    PILATUS AIRCRAFT LTD. has issued PILATUS AIRCRAFT LTD. PC-12 
Service Bulletin No: 32-020, dated July 24, 2007. The actions described 
in this service information are intended to correct the unsafe 
condition identified in the MCAI.

FAA's Determination and Requirements of the Proposed AD

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with this State of Design Authority, they 
have notified us of the unsafe condition described in the MCAI and 
service information referenced above. We are proposing this AD because 
we evaluated all information and determined the unsafe condition exists 
and is likely to exist or develop on other products of the same type 
design.

Differences Between This Proposed AD and the MCAI or Service 
Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use

[[Page 61581]]

different words from those in the MCAI to ensure the AD is clear for 
U.S. operators and is enforceable. In making these changes, we do not 
intend to differ substantively from the information provided in the 
MCAI and related service information.
    We might also have proposed different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a NOTE within the proposed AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 480 products of U.S. registry. We also estimate that 
it would take about .5 work-hour per product to comply with the basic 
requirements of this proposed AD. The average labor rate is $80 per 
work-hour.
    Based on these figures, we estimate the cost of the proposed AD on 
U.S. operators to be $19,200, or $40 per product.
    In addition, we estimate that any necessary follow-on actions would 
take about 4 work-hours and require parts costing $2,300, for a cost of 
$2,620 per product. We have no way of determining the number of 
products that may need these actions.

Authority for This Rulemaking

    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

    We 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 this 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 and placed it in the AD docket.

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 FAA 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 FAA amends Sec.  39.13 by adding the following new AD:

Pilatus Aircraft Limited: Docket No. FAA-2007-0116; Directorate 
Identifier 2007-CE-082-AD.

Comments Due Date

    (a) We must receive comments by November 30, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to PC-12, PC-12/45, and PC-12/47 airplanes, 
serial numbers 101 through 749, certificated in any category; with 
one of more of the following installed:
    (1) Main landing gear (MLG) assemblies delivered before December 
31, 2006, with the following part numbers (P/N): 532.10.12.037, 
532.10.12.038, 532.10.12.041, 532.10.12.042, 532.10.12.043, 
532.10.12.044, 532.10.12.047, 532.10.12.048, 532.10.12.049, 
532.10.12.050, 532.10.12.051, or 532.10.12.052;
    (2) Special bolts P/N 532.10.12.110, 532.10.12.205, 
532.10.12.077, or 532.10.12.202 delivered before December 31, 2006; 
or
    (3) Modification kit numbers 500.50.12.267, 500.50.12.286, or 
500.50.12.299 delivered before December 31, 2006.

Subject

    (d) Air Transport Association of America (ATA) Code 32: Landing 
Gear.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:
    It has been found that some of the above mentioned MLG special 
bolts can be defective. The problem is only applicable to specific 
bolts with serial numbers that start with the letters AT or have the 
supplier code AT. Investigations revealed that there is a 
possibility for hydrogen embrittlement which occurs during the 
manufacture process.
    Components in this condition can decrease the specific fatigue 
life and could lead to MLG collapse during operation with consequent 
loss of airplane control.
    In order to correct the situation, this AD requires the 
identification of all MLG special bolts to determine if the bolts 
have serial numbers that start with the letters AT or have the 
supplier code AT and the replacement of affected special bolts.

Actions and Compliance

    (f) Unless already done, do the following actions:
    (1) Within the next 100 hours time-in-service (TIS) after the 
effective date of this AD or within the next 3 months after the 
effective date of this AD, whichever occurs first, inspect the 
special bolts that attach the MLG retraction actuators and the 
special bolts that attach the shock absorbers to the MLG assemblies 
to identify the serial numbers that start with the letters AT or 
have the supplier code AT following PILATUS AIRCRAFT LTD. PC-12 
Service Bulletin No: 32-020, dated July 24, 2007.
    (2) If during the inspection required in paragraph (f)(1) of 
this AD any special bolts with the serial number starting with the 
letters AT or special bolts with the supplier code AT are found, 
before further flight, replace the specified bolts with new bolts 
with the new part numbers in all MLG assemblies following PILATUS 
AIRCRAFT LTD. PC-12 Service Bulletin No: 32-020, dated July 24, 
2007.
    (3) As of the effective date of this AD, do not install any of 
the special bolts that have serial numbers that start with the 
letters AT or have the supplier code AT on Models PC-12, PC-12/45, 
and PC-12/47 airplanes as indicated in PILATUS AIRCRAFT LTD. PC-12 
Service Bulletin No: 32-020, dated July 24, 2007. MLG assemblies, 
special bolts, and modifications kits, as referenced in paragraphs 
(c)(1), (c)(2), and (c)(3) of this AD, delivered from PILATUS 
AIRCRAFT LTD. on or after December 31, 2006, will not incorporate 
the unsafe condition.

FAA AD Differences

    Note: This AD differs from the MCAI and/or service information 
as follows: No differences.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
Standards Office, FAA, has the authority to approve AMOCs for this 
AD, if requested using the procedures found in 14 CFR 39.19. Send 
information to ATTN: Doug Rudolph, Aerospace Engineer, FAA, Small 
Airplane Directorate, 901 Locust,

[[Page 61582]]

Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4059; 
fax: (816) 329-4090. Before using any approved AMOC on any airplane 
to which the AMOC applies, notify your appropriate principal 
inspector (PI) in the FAA Flight Standards District Office (FSDO), 
or lacking a PI, your local FSDO.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

Related Information

    (h) Refer to Federal Office of Civil Aviation (FOCA) AD HB-2007-
382, dated August 27, 2007; and PILATUS AIRCRAFT LTD. PC-12 Service 
Bulletin No: 32-020, dated July 24, 2007, for related information.

    Issued in Kansas City, Missouri, on October 24, 2007.
Kim Smith,
Manager, Small Airplane Directorate, Aircraft Certification Service.
 [FR Doc. E7-21421 Filed 10-30-07; 8:45 am]
BILLING CODE 4910-13-P