AD Amdt-39-11319

final rule

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

AD Number
Amdt-39-11319
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 98-CE-119-AD
FR Citation
64 FR 50439
Technical illustration of an aircraft flight control surface and actuator
Problem area Flight controls

Applicability

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

Unsafe Condition

Premature wear of the internal gear system caused by excessive backlash in the flight control flap actuators, which could eventually result in loss of actuator output with possible reduced or loss of airplane control.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect all flap actuator internal gear systems to assure correct end-play and backlash measurements. Accomplish any necessary corrective adjustments.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 airplanes.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires inspecting all flap actuator internal gear systems to assure that correct end-play and backlash measurements exist, and accomplishing any corrective adjustments as necessary. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent premature wear of the internal gear system caused by excessive backlash in the flight control flap actuators, which could eventually result in loss of actuator output with possible reduced or loss of airplane control.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 64, Number 180 (Friday, September 17, 1999)]
[Rules and Regulations]
[Pages 50439-50440]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-24088]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-CE-119-AD; Amendment 39-11319; AD 99-19-32]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-
12/45 airplanes. This AD requires inspecting all flap actuator internal 
gear systems to assure that correct end-play and backlash measurements 
exist, and accomplishing any corrective adjustments as necessary. This 
AD is the result of mandatory continuing airworthiness information 
(MCAI) issued by the airworthiness authority for Switzerland. The 
actions specified by this AD are intended to prevent premature wear of 
the internal gear system caused by excessive backlash in the flight 
control flap actuators, which could eventually result in loss of 
actuator output with possible reduced or loss of airplane control.

DATES: Effective November 8, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 8, 1999.

ADDRESSES: Service information that applies to this AD may be obtained 
from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 610 33 51. 
This information may also be examined at the Federal Aviation 
Administration (FAA), Central Region, Office of the Regional Counsel, 
Attention: Rules Docket No. 98-CE-119-AD, Room 1558, 601 E. 12th 
Street, Kansas City, Missouri 64106; or at the Office of the Federal 
Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

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

SUPPLEMENTARY INFORMATION:

Events Leading to the Issuance of This AD

    A proposal to amend part 39 of the Federal Aviation Regulations (14 
CFR part 39) to include an AD that would apply to certain Pilatus 
Models PC-12 and PC-12/45 airplanes was published in the Federal 
Register as a notice of proposed rulemaking (NPRM) on June 23, 1999 (64 
FR 33445). The NPRM proposed to require inspecting all flap actuator 
internal gear systems to assure that correct end-play and backlash 
measurements exist, and accomplishing any corrective adjustments as 
necessary.
    The affected airplanes could incorporate one of the following 
flight control flap actuators:

--Pilatus part number (P/N) 978.71.20.302--Actuator, Linear (951D100-
5);
--Pilatus P/N 978.71.20.303--Actuator, Linear (951D100-7); and
--Pilatus P/N 978.71.20.304--Actuator, Linear (951D100-9).

    Accomplishment of the proposed inspection as specified in the NPRM 
would be required in accordance with Pilatus Service Bulletin No. 27-
005, dated November 18, 1998. Accomplishment of the proposed 
adjustments, if necessary, would be required in accordance with the 
maintenance manual.
    The NPRM was the result of mandatory continuing airworthiness 
information (MCAI) issued by the airworthiness authority for 
Switzerland.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were received on the 
proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination

    After careful review of all available information related to the 
subject presented above, the FAA has determined that air safety and the 
public interest require the adoption of the rule as proposed except for 
minor editorial corrections. The FAA has determined that these minor 
corrections will not change the meaning of the AD and will not add any 
additional burden upon the public than was already proposed.

Cost Impact

    The FAA estimates that 69 airplanes in the U.S. registry will be 
affected by this AD, that it will take approximately 6 workhours per 
airplane to accomplish this action, and that the average labor rate is 
approximately $60 an hour. The manufacturer will provide parts free-of-
charge to the owners/operators of the affected aircraft. Based on these 
figures, the total cost impact of this AD on U.S. operators is 
estimated to be $24,840, or $360 per airplane.

Regulatory Impact

    The regulations adopted herein will 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 final 
rule does 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) 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 final evaluation prepared for this 
action is contained 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, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation

[[Page 50440]]

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

99-19-32  Pilatus Aircraft Ltd.: Amendment 39-11319; Docket No. 98-
CE-119-AD.

    Applicability: Models PC-12 and PC-12/45 airplanes, manufacturer 
serial numbers (MSN) 101 through MSN 236; certificated in any 
category, that have one of the following flight control flap 
actuators installed:

--Pilatus part number (P/N) 978.71.20.302--Actuator, Linear 
(951D100-5);
--Pilatus P/N 978.71.20.303--Actuator, Linear (951D100-7); and
--Pilatus P/N 978.71.20.304--Actuator, Linear (951D100-9).

    Note 1: 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.
    Compliance: Required as indicated in the body of this AD, unless 
already accomplished.
    To prevent premature wear of the internal gear system caused by 
excessive backlash in the flight control flap actuators, which could 
eventually result in loss of actuator output with possible reduced 
or loss of airplane control, accomplish the following:
    (a) Within the next 50 hours time-in-service (TIS) after the 
effective date of this AD, inspect all flap actuator internal gear 
systems to assure that correct end-play and backlash measurements 
exist, in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of 
Pilatus Service Bulletin No. 27-005, dated November 18, 1998. Prior 
to further flight, perform any corrective adjustments, as necessary, 
in accordance with the maintenance manual.
    (b) As of the effective date of this AD, no person may install, 
on any affected airplane, a flap actuator that has not been 
inspected and adjusted (as necessary) as required by paragraph (a) 
this AD.

    Note 2: The FAA recommends that the most up-to-date Pilatus 
reports and revisions pertaining to this subject be incorporated 
into the Pilatus PC-12 Maintenance Manual. The most up-to-date 
documents at the date of issuance of this AD are Temporary Revision 
No. 27-04, dated November 18, 1998; and Temporary Revision No. 04-
04, dated June 16, 1999.

    (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 times 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) Questions or technical information related to Pilatus 
Service Bulletin No. 27-005, dated November 18, 1998, should be 
directed to Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 
Stans, Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 
610 33 51. This service information may be examined at the FAA, 
Central Region, Office of the Regional Counsel, Room 1558, 601 E. 
12th Street, Kansas City, Missouri 64106.
    (f) The inspections required by this AD shall be done in 
accordance with Pilatus Service Bulletin No. 27-005, dated November 
18, 1998. This incorporation by reference was approved by the 
Director of the Federal Register in accordance with 5 U.S.C. 552(a) 
and 1 CFR part 51. Copies may be obtained from Pilatus Aircraft 
Ltd., Customer Liaison Manager, CH-6371 Stans, Switzerland. Copies 
may be inspected at the FAA, Central Region, Office of the Regional 
Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at 
the Office of the Federal Register, 800 North Capitol Street, NW, 
suite 700, Washington, DC.

    Note 4: The subject of this AD is addressed in Swiss AD HB 98-
460, dated November 23, 1998.

    (g) This amendment becomes effective on November 8, 1999.

    Issued in Kansas City, Missouri, on September 9, 1999.
Michael K. Dahl,
Acting Manager, Small Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-24088 Filed 9-16-99; 8:45 am]
BILLING CODE 4910-13-P

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