[Federal Register Volume 67, Number 41 (Friday, March 1, 2002)]
[Proposed Rules]
[Pages 9420-9423]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-4865]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-CE-44-AD]
RIN 2120-AA64


Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and 
PC-12/45 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) Models PC-
12 and PC-12/45 airplanes. This proposed AD would require you to 
inspect the left and right main landing gear (MLG) assemblies for bolts 
with a serial number (S/N) beginning with the letters ``AT'' and 
numbers 299 or lower and replace each bolt with a bolt that does not 
have a S/N with both the letters ``AT'' and a number of 299 or lower. 
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 replace defective MLG assembly bolts that have an improper 
cadmium plating, which could cause hydrogen embrittlement and bolt 
failure. Such failure could lead to MLG collapse during landing.

DATES: The Federal Aviation Administration (FAA) must receive any 
comments on this proposed rule on or before April 1, 2002.

ADDRESSES: Submit comments to FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2001-CE-44-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. You may view any 
comments at this location

[[Page 9421]]

between 8 a.m. and 4 p.m., Monday through Friday, except Federal 
holidays.
    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 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 comments, you must include a self-
addressed, stamped postcard. On the postcard, write ``Comments to 
Docket No. 2001-CE-44-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 certain Pilatus Models PC-12 and PC-12/45 airplanes. The FOCA 
reports that, because of a manufacturing defect, certain bolts on the 
main landing gear (MLG) assembly may be defective. The problem is 
caused by an improper cadmium process applied to the high strength 
steel part, which can cause hydrogen embrittlement and subsequent 
failure of the bolt.
    The defective bolts were initially installed on MLG assemblies that 
have a serial number beginning with the letters ``AM''. Each bolt in 
the defective lot incorporates the letters ``AT'' and a number of 299 
or lower.
    What are the consequences if the condition is not corrected? If not 
corrected, such failure could lead to MLG collapse during landing.
    Is there service information that applies to this subject? Pilatus 
has issued Pilatus PC-12 Service Bulletin No. 32-012, dated October 18, 
2001.
    What are the provisions of this service information? The service 
bulletin includes procedures for replacing defective bolts in the main 
landing gear assemblies.
    What action did the FOCA take? The FOCA classified this service 
bulletin as mandatory and issued Swiss AD Number HB 2001-603, dated 
November 5, 2001, in order to ensure the continued airworthiness of 
these airplanes in Switzerland.
    Was this in accordance with the bilateral airworthiness agreement? 
These airplane models are manufactured in Switzerland and are 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 Models PC-12 and PC-12/45 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 
bulletin.

Cost Impact

    How many airplanes would this proposed AD impact? We estimate that 
this proposed AD affects 16 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 the proposed inspection and replacement:

----------------------------------------------------------------------------------------------------------------
                                                                      Total cost per          Total cost U.S.
             Labor cost                       Parts cost                 airplaine               operators
----------------------------------------------------------------------------------------------------------------
Manufacturer will pay for workhours  Parts will be provided at    None..................  None.
                                      no cost to the owners/
                                      operators of the affected
                                      aircraft.
----------------------------------------------------------------------------------------------------------------

Compliance Time of This Proposed AD

    What would be the compliance time of this proposed AD? The 
compliance time of this proposed AD is ``within the next 30 days after 
the effective date of this AD''.
    Why is the compliance time presented in calendar time instead of 
hours time-in-service (TIS)? Although malfunction of the main landing 
gear is unsafe during flight, the condition is not a direct result of 
airplane operation. The chance of this situation occurring is the same 
for an airplane with 10 hours TIS as it would be for an airplane with 
500 hours TIS. A calendar time for compliance would ensure that the 
unsafe condition is addressed on all airplanes in a reasonable time 
period.

[[Page 9422]]

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. 2001-CE-44-AD

    (a) What airplanes are affected by this AD? This AD affects the 
following airplane models and serial numbers that are certificated 
in any category:
    (1) Group 1: Pilatus may have installed the affected bolts on 
the following airplanes at manufacture. All portions of this AD 
apply to these airplanes:

------------------------------------------------------------------------
                 Model                            Serial numbers
------------------------------------------------------------------------
PC-12 and PC-12/45.....................  349, 352, 357, 359, 362 through
                                          365, 367, 369, 371, 375, 377,
                                          380, 384, 385, 388, 390, 391,
                                          393, 401, and 409.
------------------------------------------------------------------------

    (2) Group 2: The affected bolts could be installed through spare 
replacement on any of the following model airplanes. Paragraphs 
(d)(3) and (d)(4) of this AD apply to these airplanes:

------------------------------------------------------------------------
                   Model                           Serial numbers
------------------------------------------------------------------------
PC-12 and PC-12/45........................  All serial numbers.
------------------------------------------------------------------------

    (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 replace defective main landing 
gear (MLG) assembly bolts that have an improper cadmium plating, 
which could cause hydrogen embrittlement and bolt failure.
    (d) What actions must I accomplish to address this problem? To 
address this problem, accomplish all actions for Group 1 airplanes, 
and accomplish paragraphs (d)(3) and (d)(4) of this AD for Group 2 
airplanes:

------------------------------------------------------------------------
           Actions                 Compliance            Procedures
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(1) Inspect the left and      Inspect within the    Pilatus PC-12
 right main landing gear       next 30 days after    Service Bulletin
 (MLG) assembly for the        the effective date    No. 32-012, dated
 existence of a bolt, part     of this AD. Prior     October 18, 2001,
 number (P/N) 532.10.12.077,   to further flight,    provides
 that has a serial number (S/  replace bolts found   information about
 N) with both the letters      during the            these actions.
 ``AT'' and a number of 299    inspection required
 or lower.                     in paragraph (d)(1)
                               of this AD.
(i) If the above referenced
 bolts are not installed, no
 further action is required.
(ii) If the above referenced
 bolts are installed,
 replace each bolt with an
 FAA-approved bolt that does
 not have a S/N with both
 the letters ``AT'' and a
 number of 299 or lower.
(2) Send the removed bolts    Within 10 days after  Send the removed
 to Pilatus Aircraft Ltd. so   removing the bolts    bolts to Pilatus
 the bolts cannot be reused    or within 10 days     Aircraft Ltd. at
 and report the results of     after the effective   the address in
 the inspection (positive or   date of this AD,      paragraph (h) of
 negative) to FAA. The         whichever occurs      this AD, and send
 Office of Management and      later.                the report to Doug
 Budget (OMB) approved the                           Rudolph, FAA, at
 information collection                              the address in
 requirements contained in                           paragraph (f) of
 this regulation under the                           this AD.
 provisions of the Paperwork
 Reduction Act of 1980 (44
 U.S.C. 3501 et seq.) and
 assigned OMB Control Number
 2120-0056.
(3) Do not install any bolt,  As of the effective   Not Applicable.
 P/N 532.10.12.007, on any     date of this AD.
 MLG assembly that has a S/N
 with both the letters
 ``AT'' and a number of 299
 or lower.
(4) If you have already       Within the next 30    Not Applicable.
 accomplished the actions      days after the
 specified in Pilatus PC-12    effective date of
 Service Bulletin No. 32-      this AD.
 012, dated October 18,
 2001, send a report to the
 FAA at the address in
 paragraph (f) of this AD,
 stating if one of the
 affected bolts were
 replaced and returned to
 Pilatus.
------------------------------------------------------------------------


[[Page 9423]]

    (e) Can I comply with this AD in any other way? You may use an 
alternative method of compliance or adjust the compliance time if:
    (1) Your alternative method of compliance provides an equivalent 
level of safety; and
    (2) The Manager, Small Airplane Directorate, approves your 
alternative. Submit your request through an FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Small Airplane Directorate.

    Note 1: This AD applies to each airplane identified in paragraph 
(a) of this AD, regardless of whether it has been modified, altered, 
or repaired in the area subject to the requirements of this AD. For 
airplanes that have been modified, altered, or repaired so that the 
performance of the requirements of this AD is affected, the owner/
operator must request approval for an alternative method of 
compliance in accordance with paragraph (e) of this AD. The request 
should include an assessment of the effect of the modification, 
alteration, or repair on the unsafe condition addressed by this AD; 
and, if you have not eliminated the unsafe condition, specific 
actions you propose to address it.

    (f) Where can I get information about 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.
    (g) What if I need to fly the airplane to another location to 
comply with this AD? The FAA can issue a special flight permit under 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate your airplane to a location where 
you can accomplish the requirements of this AD.
    (h) 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 2: The subject of this AD is addressed in Swiss AD HB 2001-
603, dated November 5, 2001.


    Issued in Kansas City, Missouri, on February 21, 2002.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 02-4865 Filed 2-28-02; 8:45 am]
BILLING CODE 4910-13-P