Voglio sapere a riguardo di…

51836

Federal Register / Vol. 86, No. 178 / Friday, September 17, 2021 / Proposed Rules
hinge bolts caused by incorrect torqueing and locking of the bolts.
AD 20120616 requires installing a new elevator and rudder locking screw and modifying the installation of the elevator and rudder hinge bolt. The FAA issued AD 20120616 to prevent in-flight failure of the elevator or rudder attachment, which could result in loss of control of the airplane.
Actions Since AD 20120616 Was Issued Since the FAA issued AD 201206
16, EASA superseded EASA AD 2011
0230, dated December 9, 2011, and issued EASA AD 20210098, dated April 9, 2021 referred to after this as the MCAI. The MCAI states:
Occurrences were reported where, on certain PC6 aeroplanes, the elevator or the rudders was lost or partially detached during flight. All the occurrences happened on PC
6 aeroplanes in CONFIG 1.
This condition, if not corrected, could lead to in-flight failure of the elevator or rudder attachment, possibly resulting in reduced control of the aeroplane.
To address this potential unsafe condition, Pilatus issued SB 55001 original issue and Revision 1 to provide rework instructions for the elevator and rudder hinge bolt locking.
Consequently, EASA published AD 2011
0230 to require this rework. Subsequently, Pilatus issued recommended SB 55003
later revised to provide instructions to modify the hinge bolt installation of the elevator and rudder. This service bulletin SB, being recommended only, had no impact on the existing EASA AD.
Since that EASA AD and the recommended Pilatus SB 55003 were published, the latest risk assessment determined that the modification of the hinge bolt installation of the elevator, rudder and right-hand RH aileron installation must be required to reach an acceptable level of safety for the affected aeroplanes. Consequently,
Pilatus issued the SB, as defined in this EASA AD, to provide instructions to modify the affected aeroplanes into CONFIG 2
standard.
For the reasons described above, this EASA AD supersedes EASA AD 20110230
and requires, for certain aeroplanes, a onetime inspection of the elevator and rudder installation, followed by repetitive inspections of the elevator and rudder, and, depending on findings, accomplishment of applicable corrective actions. This EASA
AD also requires modification of the elevator, rudder and RH aileron hinge bolt installations into CONFIG 2, which is the terminating action for the repetitive inspections required by this EASA AD.
Finally, this EASA AD prohibits reinstallation of affected parts.

You may examine the MCAI in the AD docket at https
www.regulations.gov by searching for and locating Docket No. FAA2021
0786.
Related Service Information Under 1
CFR Part 51
The FAA reviewed Pilatus PC6
Service Bulletin SB No. 55005, dated February 25, 2021 Pilatus SB 55005.
The service information specifies procedures for repetitively inspecting the hinge bolt installations and taking any necessary corrective actions until the hinge bolt is modified. Modifying the hinge bolt installation in accordance with Pilatus SB 55005 makes the airplane a CONFIG 2 design. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.
Other Related Service Information Pilatus also issued Pilatus PC6 SB
No. 55003, dated November 29, 2013;

Pilatus PC6 SB No. 55003, Revision 1, dated December 9, 2014; Pilatus PC6
SB No. 55003, Revision 2, dated January 19, 2017; and Pilatus PC6 SB
No. 55003, Revision 3, dated November 6, 2017. This service information specifies procedures for modifying the hinge bolt installations, which makes the airplane a CONFIG 2
design. This service information was superseded by Pilatus SB 55005.
FAAs Determination This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to the FAAs bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI and service information referenced above. The FAA
is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.
Proposed AD Requirements in This NPRM
This proposed AD would require accomplishing the actions specified in the service information described previously. This proposed AD would not retain any actions of AD 201206
06.
Costs of Compliance The FAA estimates that this AD, if adopted as proposed, would affect 50
airplanes of U.S. registry.
The FAA estimates the following costs to comply with this proposed AD:

ESTIMATED COSTS
Cost on U.S.
operators
Action
Labor cost
Parts cost
Cost per product
Inspecting CONFIG 1 airplanes

4.5 work-hours $85 per hour =
$382.50.
14 work-hours $85 per hour = $1,190

Not applicable

$382.50 per inspection cycle.
$2,390

Modifying from CONFIG 1 to CONFIG
2.

The FAA estimates the following costs to do any necessary corrective actions that would be required based on
$1,200

the results of the proposed inspection.
The FAA has no way of determining the
$19,125 per inspection cycle.
$119,500.

number of airplanes that might need these actions:

ON-CONDITION COSTS
Action
Labor cost
Accomplishing corrective actions

.5 work-hours $85 per hour = $42.50

VerDate Sep<11>2014

15:47 Sep 16, 2021

Jkt 253001

PO 00000

Frm 00002

Fmt 4702

Sfmt 4702

E:FRFM17SEP1.SGM

Parts cost
17SEP1

$200

Cost per product $242.50