[Federal Register Volume 69, Number 57 (Wednesday, March 24, 2004)]
[Rules and Regulations]
[Pages 13712-13715]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-6260]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-CE-55-AD; Amendment 39-13531; AD 2004-06-05]
RIN 2120-AA64


Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and 
PC-12/45 Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA adopts a new airworthiness directive (AD) for all 
Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. 
This AD requires you to determine whether certain main landing gear 
shock absorber attachment bolts have been replaced and, if not 
replaced, would require you to replace shock absorber attachment bolts 
on main landing gear assemblies that have a serial number beginning 
with AM001 through AM053. This AD is the result of mandatory continuing 
airworthiness information (MCAI) issued by the airworthiness authority 
for Switzerland. We are issuing this AD to detect and correct hydrogen 
embrittlement in the main landing gear shock absorber attachment bolts, 
which could result in failure of the main landing gear. This failure 
could lead to main landing gear collapse during operation with 
consequent loss of airplane control.

DATES: This AD becomes effective on May 6, 2004.
    As of May 6, 2004, the Director of the Federal Register approved 
the incorporation by reference of certain publications listed in the 
regulation.

ADDRESSES: You may get the service information identified 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 the AD docket at FAA, Central Region, Office of the 
Regional Counsel, Attention: Rules Docket No. 2003-CE-55-AD, 901 
Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. 
to 4 p.m., Monday through Friday, except Federal holidays.

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: 

Discussion

    What events have caused this 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 Pilatus 
Models PC-12 and PC-12/45 airplanes. The FOCA reports that certain 
shock absorber attachment bolts (part number 532.10.12.110) in the main 
landing gear assemblies could fail during operation. Investigations 
revealed that an improper cadmium plating process applied to the high 
strength steel part causes the problem. This can cause hydrogen 
embrittlement.
    The only bolts affected are those installed on main landing gear 
assemblies with a serial number that starts with AM.
    What is the potential impact if FAA took no action? Failure of the 
main landing gear could lead to main landing gear collapse during 
operation with consequent loss of airplane control.
    Has FAA taken any action to this point? We issued a proposal to 
amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to 
include an AD that would apply to all Pilatus Models PC-12 and PC-12/45 
airplanes.

[[Page 13713]]

This proposal was published in the Federal Register as a notice of 
proposed rulemaking (NPRM) on January 9, 2004 (69 FR 1551). The NPRM 
proposed to require you to determine whether certain main landing gear 
shock absorber attachment bolts have been replaced and, if not 
replaced, would require you to replace shock absorber attachment bolts 
on main landing gear assemblies that have a serial number beginning 
with AM.

Comments

    Was the public invited to comment? We provided the public the 
opportunity to participate in developing this AD. The following 
presents the comments received on the proposal and FAA's response to 
each comment:

Comment Issue No. 1: Limit the Effectivity of the AD

    What is the commenter's concern? Two commenters want the 
effectivity of the AD limited to Pilatus Models PC-12 and PC-12/45 
airplanes with serial numbers 101 through 482 (as listed in Pilatus SB 
PC12 Service Bulletin No: 32-015, dated September 12, 2003). The 
commenters state that the suspected bolts have been installed on a 
limited number of landing gears. Further, it is very unlikely that 
bolts have been swapped between airplanes. The proposed effectivity to 
all serial numbers will place an undue burden on owners and operators.
    The commenters conclude that limiting the effectivity to airplanes 
with serial numbers 101 through 482 is enough to assure the 
airworthiness of Pilatus Models PC-12 and PC-12/45 airplanes.
    What is FAA's response to the concern? We believe that the practice 
of swapping bolts is rare, however, it is still possible. To help 
alleviate this possibility, we are including the action of a logbook 
check in the AD.
    We also believe that the swapping of the main landing gear 
assemblies is possible so limiting the airplane serial numbers is not 
enough to assure the airworthiness of Pilatus Models PC-12 and PC-12/45 
airplanes.
    We are not changing the final rule AD action as a result of theses 
comments.

Comment Issue No. 2: Limit Effectivity on the Shock-Absorber Attachment 
Bolts

    What is the commenter's concern? Two commenters note that main 
landing gear assemblies with new bolts (part number (P/N) 
532.10.12.110) marked ``AT'' or ``VLG'' are good bolts and do not 
require replacement.
    The commenters request limiting the effectivity of the AD to those 
P/N 532.10.12.110 bolts not marked ``AT'' or ``VLG.''
    What is FAA's response to the concern? We agree that the main 
landing gear assemblies with new bolts (part number (P/N) 
532.10.12.110) marked ``AT'' or ``VLG'' are good bolts and do not 
require replacement.
    We are changing the final rule AD action accordingly to reflect the 
commenters' request.

Comment Issue No. 3: AD Is Not Needed

    What is the commenter's concern? One commenter suggests that the 
aviation industry has influence over FAA. Further, FAA neglects the 
public's concerns.
    We infer that the commenters want us to withdraw the NPRM.
    What is FAA's response to the concern? Through the NPRM process, 
FAA provides the public opportunity to comment on and influence the AD 
action.
    Since the commenter gave no specific reasons to withdraw or change 
the proposed rule, we are not changing the final rule AD action as a 
result of these comments.

Comment Issue No. 4: Limit Effectivity on the Main Landing Gear 
Assemblies

    What is the commenter's concern? One commenter requests that FAA 
limit the effectivity on the main landing gear assemblies to those 
assemblies with the serial numbers that start ``AM001'' through 
``AM053'' since Pilatus has identified these were assembled with the 
defective bolts. The commenter notes that limiting the effectivity will 
lessen the impact on owners/operators.
    What is FAA's response to the concern? The FAA agrees that the AD 
should limit the effectivity on the main landing gear assemblies.
    We are changing the final rule AD action accordingly.

Conclusion

    What is FAA's final determination on this issue? We have carefully 
reviewed the available data and determined that air safety and the 
public interest require adopting the AD as proposed except for the 
changes discussed above and minor editorial corrections. We have 
determined that these changes and minor corrections:

--Are consistent with the intent that was proposed in the NPRM for 
correcting the unsafe condition; and
--Do not add any additional burden upon the public than was already 
proposed in the NPRM.

Changes to 14 CFR Part 39--Effect on the AD

    How does the revision to 14 CFR part 39 affect this AD? On July 10, 
2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, 
July 22, 2002), which governs the FAA's AD system. This regulation now 
includes material that relates to altered products, special flight 
permits, and alternative methods of compliance. 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.

Costs of Compliance

    How many airplanes does this AD impact? We estimate that this AD 
affects 260 airplanes in the U.S. registry.
    What is the cost impact of this AD on owners/operators of the 
affected airplanes? The manufacturer will provide parts free of charge 
and will pay for the estimated 3 workhours required to do the 
inspection and replacement of the shock absorber attachment bolts.

Compliance Time of This AD

    What will be the compliance time of this AD? The compliance time of 
this AD is within the next 30 calendar days after the effective date of 
this AD.
    Why is this compliance time presented in calendar time instead of 
hours time-in-service (TIS)? The unsafe condition exists or could 
develop on airplanes equipped with the affected parts regardless of 
airplane operation. For example, the unsafe condition has the same 
chance of occurring on an airplane with 50 hours TIS as it does on one 
with 5,000 hours TIS. Therefore, we are presenting the compliance time 
of this AD in calendar time instead of hours TIS.

Regulatory Findings

    Will this AD impact various entities? We have 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.
    Will this AD involve a significant rule or regulatory action? 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 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

[[Page 13714]]

under the criteria of the Regulatory Flexibility Act.
    We prepared a summary of the costs to comply with this AD and 
placed it in the AD Docket. You may get a copy of this summary by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-CE-55-AD'' in your request.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. FAA amends Sec.  39.13 by adding a new AD to read as follows:

2004-06-05 Pilatus Aircraft Ltd.: Amendment 39-13531; Docket No. 
2003-CE-55-AD.

When Does This AD Become Effective?

    (a) This AD becomes effective on May 6, 2004.

What Other ADs Are Affected by This Action?

    (b) None.

What Airplanes Are Affected by This AD?

    (c) This AD affects Models PC-12 and PC-12/45 airplanes, all 
serial numbers, that are certificated in any category.

What is the Unsafe Condition Presented in This AD?

    (d) This AD is the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for 
Switzerland. The actions specified in this AD are intended to detect 
and correct hydrogen embrittlement in the main landing gear shock 
absorber attachment bolts, which could result in failure of the main 
landing gear. This failure could lead to main landing gear collapse 
during operation with consequent loss of airplane control.

What Must I do To Address This Problem?

    (e) To address this problem, you must do the following:

 
------------------------------------------------------------------------
             Actions                  Compliance          Procedures
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(1) Maintenance Records Check:..  Within the next 30  No special
                                   calendar days       procedures
                                   after May 6, 2004   necessary to
                                   (the effective      check the
                                   date of this AD),   maintenance
                                   unless already      records.
                                   done.
(i) Check the maintenance
 records to determine whether
 the main landing gear (MLG)
 shock absorber attachment bolts
 (part number (P/N)
 532.10.12.110) have been
 replaced. The bolts must have
 been replaced by following
 Pilatus PC12 Service Bulletin
 No: 32-015, dated September 12,
 2003. The owner/operator
 holding at least a private
 pilot certificate as authorized
 by section 43.7 of the Federal
 Aviation Regulations (14 CFR
 43.7) may perform this check.
(ii) If, by checking the
 maintenance records, the owner/
 operator can definitely show
 that the MLG gear shock
 absorber attachment bolts (P/N
 532.10.12.110) have been
 replaced (by following Pilatus
 PC12 Service Bulletin No: 32-
 015, dated September 12, 2003),
 then report the removal of any
 bolts to FAA at the address in
 paragraph (f) of this AD. You
 must make an entry into the
 aircraft records that shows
 compliance with this portion of
 the AD in accordance with
 section 43.9 of the Federal
 Aviation Regulations (14 CFR
 43.9).
---------------------------------
(2) If you find as a result of    Within the next 30  Follow the
 the check in paragraph (e)(1)     calendar days       Accomplishment
 that there is no record of bolt   after May 6, 2004   Instructions of
 replacement, inspect the left     (the effective      Pilatus PC12
 and right MLG assemblies (P/N     date of this AD),   Service Bulletin
 532.10.12.049 and P/N             unless already      No: 32-015, dated
 532.10.12.050) for any serial     done.               September 12,
 number beginning with AM001                           2003.
 through AM053. You may choose
 to do the inspection without
 doing the logbook check.
---------------------------------
(3) If during the inspection      Before further      Follow the
 required by paragraph (e)(2) of   flight after the    Accomplishment
 this AD, you find any MLG         inspection          Instructions of
 assembly with a serial number     required by         Pilatus PC12
 beginning with AM001 through      paragraph (e)(2)    Service Bulletin
 AM053, replace any shock          of this AD.         No: 32-015, dated
 absorber bolts (P/N inspection                        September 12,
 532.10.12.110) NOT MARKED with                        2003.
 ``AT'' or ``VLG'' with new
 bolts.
---------------------------------

[[Page 13715]]

 
(4) After removal of the shock    Within the next 30  Not Applicable.
 absorber bolts (P/N               calendar days
 532.10.12.110), send the old      after May 6, 2004
 removed bolts to Pilatus.         (the effective
 Report this to FAA at the         date of this AD),
 address in paragraph (f) of       unless already
 this AD. The Office of            done..
 Management and Budget (OMB)
 approved the information
 collection requirements
 contained in this regulation
 under the provisions of the
 Paperwork Reduction Act of 1980
 (44 U.S.C. 3501 et seq.) and
 assigned OMB Control Number
 2120-0056.
---------------------------------
(5) Before installing any left    As of May 6, 2004   Follow Pilatus
 or right MLG assembly (P/N        (the effective      PC12 Service
 532.10.12.049 or P/N              date of this AD).   Bulletin No: 32-
 532.10.12.050) that has a                             015, dated
 serial number beginning with                          September 12,
 AM, ensure that the shock                             2003
 absorber bolts (P/N
 532.10.12.110) NOT MARKED with
 ``AT'' or ``VLG'' have been
 replaced, and, if not, replace
 with new bolts.
------------------------------------------------------------------------

May I Request an Alternative Method of Compliance?

    (f) You may request a different method of compliance or a 
different compliance time for this AD by following the procedures in 
14 CFR 39.19. Unless FAA authorizes otherwise, send your request to 
your principal inspector. The principal inspector may add comments 
and will send your request to the Manager, Standards Office, Small 
Airplane Directorate, FAA. 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.

Does This AD Incorporate Any Material by Reference?

    (g) You must do the actions required by this AD following the 
instructions in Pilatus PC12 Service Bulletin No: 32-015, dated 
September 12, 2003. The Director of the Federal Register approved 
the incorporation by reference of this service bulletin in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may get a 
copy 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 review 
copies at FAA, Central Region, Office of the Regional Counsel, 901 
Locust, Room 506, Kansas City, Missouri 64106; or at the Office of 
the Federal Register, 800 North Capitol Street, NW., suite 700, 
Washington, DC.

Is There Other Information That Relates to This Subject?

    (h) Swiss AD Number HB 2003-522, dated November 14, 2003, also 
addresses the subject of this AD.

    Issued in Kansas City, Missouri, on March 15, 2004.
James E. Jackson,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-6260 Filed 3-23-04; 8:45 am]
BILLING CODE 4910-13-P