[Federal Register: April 4, 2003 (Volume 68, Number 65)]
[Proposed Rules]
[Page 16458-16460]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr04ap03-19]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-CE-12-AD]
RIN 2120-AA64
Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-6
Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes to adopt a new airworthiness directive
(AD) that would apply to all Pilatus Aircraft Ltd. (Pilatus) Model PC-6
airplanes. This proposed AD would require you to inspect the integral
fuel tank wing ribs for cracks and the top and bottom wing skins for
distortion and repair before further flight, and accomplish a fuel tank
ventilating system installation. This proposed AD is the result of
mandatory continuing airworthiness information (MCAI) issued by the
airworthiness authority for Switzerland. The actions specified by this
proposed AD are intended to detect and correct cracks in the ribs of
the inboard integral fuel tanks in the left and right wings, which
could lead to wing failure during flight.
DATES: The Federal Aviation Administration (FAA) must receive any
comments on this proposed rule on or before May 12, 2003.
ADDRESSES: Submit comments to FAA, Central Region, Office of the
Regional Counsel, Attention: Rules Docket No. 2003-CE-12-AD, 901
Locust, Room 506, Kansas City, Missouri 64106. You may view any
comments at this location between 8 a.m. and 4 p.m., Monday through
Friday, except Federal holidays. You may also send comments
electronically to the following address: 9-ACE-7-Docket@faa.gov.
Comments sent electronically must contain ``Docket No. 2003-CE-12-AD''
in the subject line. If you send comments electronically as attached
electronic files, the files must be formatted in Microsoft Word 97 for
Windows or ASCII text.
You may get service information that applies to this proposed AD
from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans,
Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 619 6224;
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 also view this information at
the Rules Docket at the address above.
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? The FAA invites comments on
this proposed rule. You may submit whatever written data, views, or
arguments you choose. You need to include the rule's docket number and
submit your comments to the address specified under the caption
ADDRESSES. We will consider all comments received on or before the
closing date. We may amend this proposed rule in light of comments
received. Factual information that supports your ideas and suggestions
is extremely helpful in evaluating the effectiveness of this proposed
AD action and determining whether we need to take additional rulemaking
action.
Are there any specific portions of this proposed AD I should pay
attention to? The FAA specifically invites comments on the overall
regulatory, economic, environmental, and energy aspects of this
proposed rule that might suggest a need to modify the rule. You may
view all comments we receive before and after the closing date of the
rule in the Rules Docket. We will file a report in the Rules Docket
that summarizes each
[[Page 16459]]
contact we have with the public that concerns the substantive parts of
this proposed AD.
How can I be sure FAA receives my comment? If you want FAA to
acknowledge the receipt of your mailed comments, you must include a
self-addressed, stamped postcard. On the postcard, write ``Comments to
Docket No. 2003-CE-12-AD.'' We will date stamp and mail the postcard
back to you.
Discussion
What events have caused this proposed 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 Model PC-6 airplanes. The FOCA reports an incident where
cracks have been found in the ribs of the inboard integral fuel tanks
in the left and right wings of a Model PC-6 airplane. Investigation
revealed that the cracks can occur when there are excessive pressure
differentials between the ambient air pressure and that of the fuel
tanks. The effect of this differential can be to compress the wing in
the area of the fuel tank and cause distortion of the related
structure. This distortion may result in fatigue cracks on ribs within
the wing.
What are the consequences if the condition is not corrected? These
fatigue cracks on the ribs within the wing could lead to wing failure
during flight.
Is there service information that applies to this subject? Pilatus
has issued the following:
--Service Bulletin (SB) No. 57-002, dated November 27, 2002; and
--SB No. 118, dated December 1972.
What are the provisions of this service information? The service
bulletins include procedures for:
--Inspecting the ribs in the left and right inboard fuel tanks;
--Repairing a rib;
--Inspecting to determine if the inboard fuel tank vent system is
installed; and
--Installing the inboard fuel tank vent system.
What action did the FOCA take? The FOCA classified this service
bulletin as mandatory and issued Swiss AD Number HB 2003-092, dated
February 17, 2003, in order to ensure the continued airworthiness of
these airplanes in Switzerland.
Was this in accordance with the bilateral airworthiness agreement?
This airplane model is manufactured in Switzerland and is type
certificated for operation in the United States under the provisions of
Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the
applicable bilateral airworthiness agreement.
Pursuant to this bilateral airworthiness agreement, the FOCA has
kept FAA informed of the situation described above.
The FAA's Determination and an Explanation of the Provisions of This
Proposed AD
What has FAA decided? The FAA has examined the findings of the
FOCA; reviewed all available information, including the service
information referenced above; and determined that:
--The unsafe condition referenced in this document exists or could
develop on other Pilatus Model PC-6 airplanes of the same type design
that are on the U.S. registry;
--The actions specified in the previously-referenced service
information should be accomplished on the affected airplanes; and
--AD action should be taken in order to correct this unsafe condition.
What would this proposed AD require? This proposed AD would require
you to incorporate the actions in the previously-referenced service
bulletins.
How does the revision to 14 CFR part 39 affect this proposed AD? On
July 10, 2002, FAA published a new version of 14 CFR part 39 (67 FR
47997, July 22, 2002), which governs FAA's AD system. This regulation
now includes material that relates to special flight permits,
alternative methods of compliance, and altered products. 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.
Cost Impact
How many airplanes would this proposed AD impact? We estimate that
this proposed AD affects 35 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 inspection:
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Total cost
Labor cost Parts cost per Total cost on U.S. operators
airplane
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5 workhours x $60 per hour = $300. Not applicable........... $300 $300 x 35 = $10,500.
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We estimate the following costs for each rib to accomplish any
necessary rib repair that would be required based on the results of
this proposed inspection. We have no way of determining the number of
airplanes that may need such repair.
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Total cost per rib
Labor cost Parts cost per airplane
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3 workhours x $60 per hour = $50 per rib...... $230 per rib.
$180 per rib.
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We estimate the following costs to install any inboard fuel tank
vent system that would be required based on the results of this
proposed inspection. We have no way of determining the number of
airplanes that may need such installation.
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Total cost per
Labor cost Parts cost airplane
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12 workhours x $60 per hour = $720...... $200 $920
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[[Page 16460]]
Regulatory Impact
Would this proposed AD impact various entities? The regulations
proposed herein 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. Therefore, it is determined that this
proposed rule would not have federalism implications under Executive
Order 13132.
Would this proposed AD involve a significant rule or regulatory
action? For the reasons discussed above, I certify that this proposed
action (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) if
promulgated, 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. A copy of the draft regulatory
evaluation prepared for this action has been placed in the Rules
Docket. A copy of it may be obtained by contacting the Rules Docket at
the location provided under the caption ADDRESSES.
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
part 39 of the Federal Aviation Regulations (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. FAA amends Sec. 39.13 by adding a new airworthiness directive
(AD) to read as follows:
Pilatus Aircraft Ltd.: Docket No. 2003-CE-12-AD
(a) What airplanes are affected by this AD? This AD affects
Model PC-6 airplanes, all manufacturer serial numbers (MSN) up to
and including 939, that are certificated in any category.
(b) Who must comply with this AD? Anyone who wishes to operate
any of the airplanes identified in paragraph (a) of this AD must
comply with this AD.
(c) What problem does this AD address? The actions specified by
this AD are intended to detect and correct cracks in the ribs of the
inboard integral fuel tanks in the left and right wings, which could
lead to wing failure during flight.
(d) What actions must I accomplish to address this problem? To
address this problem, you must accomplish the following:
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Actions Compliance Procedures
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(1) Inspect:
(i) The ribs in the Within the next 100 In accordance with
inboard integral fuel hours time-in- Pilatus Aircraft
tanks and related service (TIS) after Ltd. PC-6 Service
structure in the left the effective date Bulletin No. 57-
and right wings for of this AD, unless 002, dated November
crack damage;. already 27, 2002, and the
accomplished. applicable manual.
(ii) The upper and lower
wing skins for damage;
and.
(iii) To determine if
the inboard fuel tank
vent system is
installed.
(2) If crack damage is
found:
(i) Correct the crack Prior to further In accordance with
damage designated as flight after the Pilatus Aircraft
repairable in the inspections Ltd. PC-6 Service
service bulletin. required in Bulletin No. 57-
paragraph (d)(1) of 002, dated November
this AD. 27, 2002, and the
applicable
maintenance manual.
(ii) For other crack
damage, obtain a repair
scheme from the
manufacturer through
FAA at the address
specified in paragraph
(e) of this AD and
incorporate this repair
scheme.
(3) If wing distortion is Prior to further In accordance with
found, obtain a repair flight after the Pilatus Aircraft
scheme from the inspections Ltd. PC-6 Service
manufacturer through FAA at required in Bulletin No. 57-
the address specified in paragraph (d)(1) of 002, dated November
paragraph (e) of this AD this AD. 27, 2002, and the
and incorporate this repair applicable
scheme. maintenance manual.
(4) If the inboard fuel tank Prior to further In accordance with
vent system is not flight after the Pilatus Aircraft
installed, install the inspections Ltd. PC-6 Service
inboard fuel tank vent required in Bulletin No. 118,
system. paragraph (d)(1) of dated December
this AD. 1972, and the
applicable
maintenance manual.
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(e) Can I comply with this AD in any other way? To use an
alternative method of compliance or adjust the compliance time,
follow the procedures in 14 CFR 39.19. Send these requests to the
Manager, Standards Office, Small Airplane Directorate. 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.
(f) How do I get copies of the documents referenced in this AD?
You may get copies of the documents referenced in this AD from
Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans,
Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 619
6224; 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
these documents at FAA, Central Region, Office of the Regional
Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106.
Note: The subject of this AD is addressed in Swiss AD Number HB
2003-092, dated February 17, 2003.
Issued in Kansas City, Missouri, on March 28, 2003.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 03-8199 Filed 4-3-03; 8:45 am]
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