[Federal Register: September 15, 2006 (Volume 71, Number 179)]
[Proposed Rules]
[Page 54441-54443]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr15se06-16]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2006-25582; Directorate Identifier 2006-CE-42-AD]
RIN 2120-AA64
Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-7
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
certain Pilatus Aircraft Ltd. (Pilatus) Model PC-7 airplanes. This
proposed AD would require you to do repetitive eddy-current, non-
destructive inspections of the nose skin and adjacent structure above
the left and right main landing gear bay and repetitive visual
inspections of the forward support structure of the floor panel for
crack damage. If you find any crack damage, this proposed AD would
require you to contact Pilatus to obtain a repair solution and
incorporate the repair. This proposed AD results from mandatory
continuing airworthiness information (MCAI) issued by the airworthiness
authority for Switzerland. We are proposing this AD to detect and
correct cracks in the nose skin and adjacent structure above the left
and right main landing gear bay and in the forward support structure of
the floor panel. Crack propagation in certain areas could lead to
failure of the main wing torsion box, which could result in loss of
control.
DATES: We must receive comments on this proposed AD by October 16,
2006.
ADDRESSES: Use one of the following addresses to comment on this
proposed AD:
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 20590-0001.
Fax: (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.
For service information identified in this proposed AD, contact
Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans,
Switzerland; telephone: +41 41 619 63 19; fax: +41 41 619 6224.
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
We invite you to send any written relevant data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include the docket number, ``FAA-
2006-25582; Directorate Identifier 2006-CE-42-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 we
receive concerning this proposed AD.
Discussion
The Federal Office for Civil Aviation (FOCA), which is the
airworthiness authority for Switzerland, notified FAA that an unsafe
condition may exist on certain Pilatus PC-7 airplanes. The FOCA reports
crack damage in some radii at the rear edge of the nose skin, part
number (P/N) 111.34.07.434. The radii are adjacent to the left and
right corners at the forward edge of the floor panel, P/N
111.34.07.530. Crack damage can also occur in the forward support
structure of the floor panel adjacent to the skin panel.
This condition, if not detected and corrected, could result in
crack propagation in certain areas, which may lead to failure of the
main wing torsion box. This failure could result in loss of control.
Relevant Service Information
We have reviewed Pilatus PC-7 Service Bulletin No. 57-009, dated
January 29, 2004. The service information describes procedures for
visually inspecting the forward support
[[Page 54442]]
structure of the floor panel and eddy-current, non-destructive
inspecting the nose skin and adjacent structure above the left and
right main landing gear bay for crack damage.
Foreign Airworthiness Authority Information
The FOCA classified this service bulletin as mandatory and issued
Swiss AD HB 2006-374, effective date August 2, 2006, to ensure the
continued airworthiness of these airplanes in Switzerland.
These Pilatus PC-7 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 the Proposed AD
We are proposing this AD because we have examined the FOCA's
findings, evaluated all information and determined the unsafe condition
described previously is likely to exist or develop on other products of
the same type design that are certificated for operation in the United
States.
This proposed AD would require you to do repetitive eddy-current,
non-destructive inspections of the nose skin and adjacent structure
above the left and right main landing gear bay and repetitive visual
inspections of the forward support structure of the floor panel for
crack damage. If you find any crack damage, this proposed AD would
require you to contact Pilatus to obtain a repair solution and
incorporate the repair.
Differences Between the FOCA AD, the Service Information, and This
Proposed AD
FOCA AD HB-2006-374, effective date August 2, 2006, allows
continued flight if cracks are found in the nose skin that do not
exceed certain limits. The applicable service bulletin specifies repair
of the nose skin only if cracks are found exceeding limits illustrated
in Pilatus PC-7 Service Bulletin No. 57-009, dated January 29, 2004, as
does FOCA AD HB-2006-374, effective date August 2, 2006. This proposed
AD, if adopted, does not allow continued flight if any crack is found.
FAA policy is to disallow airplane operation when known cracks exist in
primary structure, unless the ability to sustain ultimate load with
these cracks is proven. The nose skin is considered primary structure,
and the FAA has not received any analysis to prove that ultimate load
can be sustained with cracks in this area.
The requirements of this proposed AD, if adopted as a final rule,
would take precedence over the provisions in the service information.
Costs of Compliance
We estimate that this proposed AD would affect 10 airplanes in the
U.S. registry.
We estimate the following costs to do the proposed inspection:
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Total cost on
Labor cost Parts cost Total cost per U.S.
airplane operators
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3 work-hours x $80 per hour = $240... No parts required....... $240 $2,400
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Any required ``upon-condition'' repairs would vary depending upon
the damage found. Based on this, we have no way of determining the
potential repair costs for each airplane or the number of airplanes
that would need the repairs based on the result of the proposed
inspections.
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 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 and placed it in the AD docket.
Examining the AD Docket
You may examine the AD docket that contains the proposed AD, the
regulatory evaluation, any comments received, and other information on
the Internet at http://dms.dot.gov; or in person at the Docket
Management Facility between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays. The Docket Office (telephone (800) 647-5227)
is located at the street address stated in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.
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.
[[Page 54443]]
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new AD:
Pilatus Aircraft Ltd.: Docket No. FAA-2006-25582; Directorate
Identifier 2006-CE-42-AD.
Comments Due Date
(a) We must receive comments on this airworthiness directive
(AD) action by October 16, 2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Model PC-7 airplanes, manufacturer serial
numbers 101 through 618 inclusive, that are certificated in any
category.
Unsafe Condition
(d) This AD results from mandatory continuing airworthiness
information (MCAI) issued by the airworthiness authority for
Switzerland. We are issuing this AD to detect and correct cracks in
the nose skin and adjacent structure above the left and right main
landing gear bay and in the forward support structure of the floor
panel. Crack propagation in certain areas could lead to failure of
the main wing torsion box. This failure could result in loss of
control.
Compliance
(e) To address this problem, you must do the following:
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Actions Compliance Procedures
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(1) Inspect: Initially inspect Do the initial
(i) The forward area of the within the next 150 inspection
floor panel and the related hours time-in- following Pilatus
structure for cracks using service or 6 PC-7 Service
magnified, visual methods. calendar months, Bulletin No. 57-
(ii) The nose skin and whichever occurs 009, dated January
adjacent structure above first, after the 29, 2004. Do the
the left and right main effective date of repetitive
landing gear bay for cracks this AD, unless inspections
using eddy-current, non- already done. following the
destructive methods. Repetitively procedures in AMM
inspect thereafter 57-10-03, dated
at intervals March 4, 2005, and
specified in AMM 05-30-05, dated
paragraph 2. B. of February 28, 2006.
Pilatus PC-7
Aircraft
Maintenance Manual
(AMM) 05-10-00,
dated March 4, 2005.
(2) If crack damage is found Before further Obtain an FAA-
during any inspection flight after any approved repair
required by paragraph inspection in which solution from the
(e)(1) of this AD, obtain crack damage is manufacturer
an FAA-approved repair found. Further through the FAA at
solution from the flight with crack the address
manufacturer through the damage is not specified in
FAA at the address permitted. After paragraph (f) of
specified in paragraph (f) incorporating the this AD and
of this AD and incorporate repair, incorporate the
the repair. repetitively repair.
inspect as
specified in
paragraph (e)(1) of
this AD.
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Alternative Methods of Compliance (AMOCs)
(f) The Manager, Standards Staff, FAA, ATTN: Doug Rudolph,
Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust,
Room 301, Kansas City, Missouri 64106; telephone: (816) 329-4059;
facsimile: (816) 329-4090, has the authority to approve AMOCs for
this AD, if requested using the procedures found in 14 CFR 39.19.
Related Information
(g) The Federal Office for Civil Aviation Swiss AD HB-2006-374,
effective date August 2, 2006, also addresses the subject of this
AD. To get copies of the service information referenced in this AD,
contact Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371
Stans, Switzerland; telephone: +41 41 619 63 19; fax: +41 41 619
6224. 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-2006-25582;
Directorate Identifier 2006-CE-42-AD.
Issued in Kansas City, Missouri, on September 11, 2006.
John R. Colomy,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E6-15342 Filed 9-14-06; 8:45 am]
BILLING CODE 4910-13-P