[Federal Register Volume 62, Number 193 (Monday, October 6, 1997)]
[Proposed Rules]
[Pages 52055-52057]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-26411]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-45-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 certain Pilatus Aircraft Ltd. (Pilatus) Models 
PC-12 and PC-12/45 airplanes. The proposed action would require 
inspecting the aileron tie-rod jam nuts for looseness, tightening any 
loose jam nuts, and installing a locking sleeve on both ends of the 
aileron tie-rod in the chain-drive of the aileron system. The proposed 
AD results from an incident where the aileron tie-rod jam nuts on the 
chain-drive of the aileron system became loose. This caused a 
differential of aileron control between the pilot's control wheel and 
the co-pilot's control wheel. The actions specified by the proposed AD 
are intended to prevent such aileron control differential caused by the 
aileron tie-rod jam nuts becoming loose, which could result in loss of 
aileron control and consequent loss of control of the airplane.

DATES: Comments must be received on or before November 7, 1997.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 97-CE-45-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106. Comments may be inspected at this location 
between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted.
    Service information that applies to the proposed AD may be obtained 
from Pilatus Aircraft Ltd., CH-6370 Stans, Switzerland. This 
information also may be examined at the Rules Docket at the address 
above.

FOR FURTHER INFORMATION CONTACT: Mr. Roman T. Gabrys, Aerospace 
Engineer, Small Airplane Directorate, Airplane Certification Service, 
FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106; telephone 
(816) 426-6932; facsimile (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of

[[Page 52056]]

the proposed rule. All comments submitted will be available, both 
before and after the closing date for comments, in the Rules Docket for 
examination by interested persons. A report that summarizes each FAA-
public contact concerned with the substance of this proposal will be 
filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 97-CE-45-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Central Region, Office of the Assistant Chief Counsel, 
Attention: Rules Docket No. 97-CE-45-AD, Room 1558, 601 E. 12th Street, 
Kansas City, Missouri 64106.

Discussion

    The Federal Office for Civil Aviation (FOCA), which is the 
airworthiness authority for Switzerland, recently notified the FAA that 
an unsafe condition may exist on Pilatus Models PC-12 and PC-12/45 
airplanes. The FOCA of Switzerland reports an incident where the 
aileron tie-rod jam nuts on the chain-drive of the aileron system 
became loose. This caused a differential of aileron control between the 
pilot's control wheel and the co-pilot's control wheel. This condition, 
if not corrected in a timely manner, could result in loss of aileron 
control and consequent loss of control of the airplane.

Applicable Service Information

    Pilatus has issued Service Bulletin No. 27-001, dated March 25, 
1997, which includes procedures for the following on Pilatus Models PC-
12 and PC-12/45 airplanes:

--inspecting the aileron tie-rod jam nuts for looseness and tightening 
any loose jam nuts; and
--installing a locking sleeve on both ends of the aileron tie-rod in 
the chain-drive of the aileron system.

    The FOCA of Switzerland classified this service bulletin as 
mandatory and issued Swiss FOCA AD HB 97-174, dated April 30, 1997, in 
order to assure the continued airworthiness of these airplanes in 
Switzerland.

Evaluation of All Applicable Information

    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 of Switzerland has kept the 
FAA informed of the situation described above.
    The FAA has examined the findings of the FOCA of Switzerland; 
reviewed all available information, including the service information 
referenced above; and determined that AD action is necessary for 
products of this type design that are certificated for operation in the 
United States.

Explanation of the Provisions of the Proposed AD

    Since an unsafe condition has been identified that is likely to 
exist or develop in other Pilatus Models PC-12 and PC-12/45 airplanes 
of the same type design that are registered in the United States, the 
FAA is proposing AD action. The proposed AD would require inspecting 
the aileron tie-rod jam nuts for looseness, tightening any loose jam 
nuts, and installing a locking sleeve on both ends of the aileron tie-
rod in the chain-drive of the aileron system. Accomplishment of the 
proposed actions would be in accordance with Pilatus Service Bulletin 
No. 27-001, dated March 25, 1997.

Cost Impact

    The FAA estimates that 40 airplanes in the U.S. registry would be 
affected by the proposed AD, that it would take approximately 5 
workhours per airplane to accomplish the proposed action, and that the 
average labor rate is approximately $60 an hour. Parts will be provided 
by the manufacturer at no cost to the owner/operator of the affected 
airplanes. Based on these figures, the total cost impact of the 
proposed AD on U.S. operators is estimated to be $12,000 or $300 per 
airplane.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this 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, pursuant to 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 USC 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding a new airworthiness directive 
(AD) to read as follows:

Pilatus Aircraft Ltd.: Docket No. 97-CE-45-AD.
    Applicability: Models PC-12 and PC-12/45 airplanes, serial 
numbers 101 through 169, certificated in any category.

    Note 1: The modification required by this AD is incorporated at 
manufacture on Models PC-12 and PC-12/45 airplanes, beginning with 
serial number 170. Airplanes with this modification are not affected 
by this AD.
    Note 2: This AD applies to each airplane identified in the 
preceding applicability provision, 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 (d) 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 the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.


[[Page 52057]]


    Compliance: Required within the next 100 hours time-in-service 
after the effective date of this AD, unless already accomplished.
    To prevent a differential of aileron control between the pilot's 
control wheel and the co-pilot's control wheel caused by the aileron 
tie-rod jam nuts becoming loose, which could result in loss of 
aileron control and consequent loss of control of the airplane, 
accomplish the following:
    (a) Inspect the aileron tie-rod jam nuts for looseness in 
accordance with the Accomplishment Instructions section of Pilatus 
Service Bulletin No. 27-001, dated March 25, 1997. Prior to further 
flight, tighten any loose jam nuts in accordance with this service 
bulletin.
    (b) Install a locking sleeve on both ends of the aileron tie-rod 
in the chain-drive of the aileron system in accordance with the 
Accomplishment Instructions section of Pilatus Service Bulletin No. 
27-001, dated March 25, 1997.
    (c) Special flight permits may be issued in accordance with 
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
21.197 and 21.199) to operate the airplane to a location where the 
requirements of this AD can be accomplished.
    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an equivalent level of safety may be 
approved by the Manager, Small Airplane Directorate, 1201 Walnut, 
suite 900, Kansas City, Missouri 64106. The request shall be 
forwarded through an appropriate FAA Maintenance Inspector, who may 
add comments and then send it to the Manager, Small Airplane 
Directorate.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Small Airplane Directorate.

    (e) All persons affected by this directive may obtain copies of 
the documents referred to herein upon request to Pilatus Aircraft 
Ltd., CH-6370 Stans, Switzerland; or may examine these documents at 
the FAA, Central Region, Office of the Assistant Chief Counsel, Room 
1558, 601 E. 12th Street, Kansas City, Missouri 64106.

    Note 4: The subject of this AD addresses the actions specified 
in Swiss AD FOCA AD HB 97-174, dated April 30, 1997.

    Issued in Kansas City, Missouri, on September 30, 1997.
Michael Gallagher,
Manager, Small Airplane Directorate, Aircraft Certification Service.
[FR Doc. 97-26411 Filed 10-3-97; 8:45 am]
BILLING CODE 4910-13-U