
[Federal Register: July 30, 2008 (Volume 73, Number 147)]
[Rules and Regulations]               
[Page 44145-44147]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30jy08-6]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0822; Directorate Identifier 2008-CE-045-AD; 
Amendment 39-15621; AD 2008-16-03]
RIN 2120-AA64

 
Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-6 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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

    This Airworthiness Directive (AD) is prompted due to the 
discovery of cracked or broken leaf springs P/N 6232.0175.01 
installed in the overhead flap-operating mechanism of some PC-6 
aircraft. A broken leaf spring could lead to an uncommanded flap 
retraction which could lead to hazardous situations and subsequent 
loss of control of the aircraft.

This AD requires actions that are intended to address the unsafe 
condition described in the MCAI.

DATES: This AD becomes effective August 11, 2008.
    On August 11, 2008, the Director of the Federal Register approved 
the incorporation by reference of certain publications listed in this 
AD.
    We must receive comments on this AD by August 29, 2008.

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

SUPPLEMENTARY INFORMATION:

Discussion

    The Federal Office of Civil Aviation (FOCA), which is the aviation 
authority for Switzerland, has issued FOCA EMERGENCY AD HB-2008-242

[[Page 44146]]

(referred to after this as ``the MCAI''), to correct an unsafe 
condition for the specified products. The MCAI states:

    This Airworthiness Directive (AD) is prompted due to the 
discovery of cracked or broken leaf springs P/N 6232.0175.01 
installed in the overhead flap-operating mechanism of some PC-6 
aircraft. A broken leaf spring could lead to an uncommanded flap 
retraction which could lead to hazardous situations and subsequent 
loss of control of the aircraft.
    This AD is published by Federal Office of Civil Aviation (FOCA) 
Switzerland, as State of production and because it is possible that 
the leaf springs were not manufactured properly.
    In order to correct and control the situation, this AD requires 
the initial and repetitive inspections of the leaf springs in the 
flap operating mechanism and the replacement of broken parts.

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

Relevant Service Information

    Pilatus Aircraft Limited has issued Pilatus PC-6 Service Bulletin 
No. 27-002 and Pilatus PC-6 Service Bulletin 27-003, both dated July 2, 
2008. 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 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 issuing this AD because we 
evaluated all information provided by the State of Design Authority and 
determined the unsafe condition exists and is likely to exist or 
develop on other products of the same type design.

Differences Between This 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 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.
    The MCAI allows for replacement parts with like parts that are 
prone to cracking. The reason for the 25-hour repetitive inspection is 
because the cracks are occurring quickly. We believe that allowing 
replacement with the same part numbers that are cracking when improved 
design part numbers exist allows the unsafe condition to continue. 
Therefore we are requiring replacement with the new improved part 
numbers if cracks are found.

FAA's Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this AD. The FAA has found that the risk to the flying public justifies 
waiving notice and comment prior to adoption of this rule because a 
broken leaf spring could lead to an uncommanded flap retraction and 
lead to loss of control during final approach. Therefore, we determined 
that notice and opportunity for public comment before issuing this AD 
are impracticable and that good cause exists for making this amendment 
effective in fewer than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not precede it by notice and opportunity for public 
comment. We invite you to send any written relevant data, views, or 
arguments about this AD. Send your comments to an address listed under 
the ADDRESSES section. Include ``Docket No. FAA-2008-0822; Directorate 
Identifier 2008-CE-045-AD'' at the beginning of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this AD. We will consider all 
comments received by the closing date and may amend this 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 AD.

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 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.
    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 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 AD and placed it in the AD docket.

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

2008-16-03 Pilatus Aircraft Limited: Amendment 39-15621; Docket No. 
FAA-2008-0822; Directorate Identifier 2008-CE-045-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective August 
11, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Models PC-6, PC-6-H1, PC-6-H2, PC-6/350, 
PC-6/350-H1,

[[Page 44147]]

PC-6/350-H2, PC-6/A, PC-6/A-H1, PC-6/A-H2, PC-6/B-H2, PC-6/B1-H2, 
PC-6/B2-H2, PC-6/B2-H4, PC-6/C-H2, and PC-6/C1-H2 airplanes, 
manufacturer serial numbers (MSN) MSN 101 through MSN 999 and MSN 
2001 through MSN 2092, certificated in any category, with 
mechanically operated flaps and leaf springs, part number (P/N) 
6232.0175.01 installed in the overhead flap-operating mechanism.

    Note: These airplanes may also be identified as Fairchild 
Republic Company PC-6 airplanes, Fairchild Heli Porter PC-6 
airplanes, or Fairchild-Hiller Corporation PC-6 airplanes.

Subject

    (d) Air Transport Association of America (ATA) Code 27: Flight 
Controls.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:
    This Airworthiness Directive (AD) is prompted due to the 
discovery of cracked or broken leaf springs P/N 6232.0175.01 
installed in the overhead flap-operating mechanism of some PC-6 
aircraft. A broken leaf spring could lead to an uncommanded flap 
retraction which could lead to hazardous situations and subsequent 
loss of control of the aircraft.
    This AD is published by Federal Office of Civil Aviation (FOCA) 
Switzerland, as State of production and because it is possible that 
the leaf springs were not manufactured properly.
    In order to correct and control the situation, this AD requires 
the initial and repetitive inspections of the leaf springs in the 
flap operating mechanism and the replacement of broken parts.

Actions and Compliance

    (f) Unless already done, do the following actions:
    (1) Before the next flight after the effective date of this AD, 
do a visual inspection of the leaf springs installed in the overhead 
flap-operating mechanism for cracks following Pilatus Aircraft Ltd. 
Pilatus PC-6 Service Bulletin No. 27-002, dated July 2, 2008.
    (2) If any cracks are found in the leaf springs installed in the 
overhead flap-operating mechanism, before further flight, remove the 
three leaf springs, P/N 6232.0175.01, installed in the overhead 
flap-operating mechanism, and replace with three new leaf springs, 
P/N 116.45.06.040, in the overhead flap-operating mechanism 
following Pilatus Aircraft Ltd. Pilatus PC-6 Service Bulletin No. 
27-003, dated July 2, 2008.
    (3) Repetitively inspect thereafter at intervals not to exceed 
25 hours time-in-service following Pilatus Aircraft Ltd. Pilatus PC-
6 Service Bulletin No. 27-002, dated July 2, 2008, until the 
modification required in paragraph (f)(2) of this AD is done. If any 
cracks are found in the leaf springs installed in the overhead flap-
operating mechanism, before further flight, remove the three leaf 
springs, P/N 6232.0175.01, and replace with three new leaf springs, 
P/N 116.45.06.040, following Pilatus Aircraft Ltd. Pilatus PC-6 
Service Bulletin No. 27-003, dated July 2, 2008.
    (4) As of the effective date of this AD, do not install any P/N 
6232.0175.01 leaf spring in the overhead flap-operating mechanism.

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, 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.

Special Flight Permit

    (h) If cracks are detected during the inspection required in 
(f)(1) or (f)(3) of this AD, no further flight is permitted until 
the modification required in paragraph (f)(2) or (f)(3) of this AD 
is done.

Related Information

    (i) Refer to MCAI FOCA EMERGENCY AD HB-2008-242, dated July 4, 
2008, and Pilatus Aircraft Ltd. Pilatus PC-6 Service Bulletin No. 
27-002 and Pilatus Aircraft Ltd. Pilatus PC-6 Service Bulletin 27-
003, both dated July 2, 2008, for related information.

Material Incorporated by Reference

    (j) You must use Pilatus Aircraft Ltd. Pilatus PC-6 Service 
Bulletin No. 27-002 and Pilatus Aircraft Ltd. Pilatus PC-6 Service 
Bulletin 27-003, both dated July 2, 2008 to do the actions required 
by this AD, unless the AD specifies otherwise.
    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (2) For service information identified in this AD, contact 
Pilatus Aircraft Ltd., Customer Liaison Manager, CH 6371 STANS, 
Switzerland; telephone: + 41 (0)41 619 6580; fax: + 41 (0)41 619 
6576; e-mail: fodermatt@pilatus aircaft.com.
    (3) You may review copies at the 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/cfr/ibr-locations.html.

    Issued in Kansas City, Missouri, on July 23, 2008.
John Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E8-17331 Filed 7-29-08; 8:45 am]

BILLING CODE 4910-13-P
