Eagle ICA-D212-725, Instructions Manual

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ICA-D212-725 (67)
Page 45 of 55
CHAPTER 67 – FLIGHT CONTROLS (67-00-00)

COPYRIGHT

2007 BY DART AEROSPACE LTD.

THIS DOCUMENT IS PRIVATE AND CONFIDENTIAL AND IS SUPPLIED ON THE EXPRESS CONDITION THAT IT IS NOT TO BE USED FOR ANY PURPOSE OR COPIED OR COMMUNICATED TO
ANY OTHER PERSON WITHOUT WRITTEN PERMISSION FROM DART AEROSPACE LTD.
Revision:
6
Date: 13.08.26
67.4 ANTI-TORQUE CONTROL
67.4.1
Anti-Torque Control System
67.4.2 Anti-Torque
Controls
The anti-torque control system. includes control
pedals, pedal adjusters, a force gradient
(centering spring) assembly with an electrically
operated magnetic brake, a hydraulic power
cylinder, and connecting linkage. Actuation of
pedals causes a power-assisted pitch change of
tail rotor blades to offset main rotor torque and
control directional heading of helicopter. Refer to
appropriate Service Instruction for maintenance
practices on copilot dual controls kit.
67.4.3 Minimum Friction Adjustment
NOTE
Helicopter S/N 30850 and subsequent require
minimum friction adjustment.
67.4.3.1
Disconnect force gradient (31,
Figure 67-5) from pedal adjuster (28). Disconnect
control tube (25) from walking beam (26).
67.4.3.2
Adjust friction screw (35) in friction
clamp (34) until a force of 4.25 to 4.75 lbs. (18.9 to
21.1 Nm) is measured at pedals moving through
neutral position.
67.4.3.3
Install force gradient (31) and
control tube (25).
67.4.4 Pedals and Adjuster
A set of control pedals, supported on forward
bulkhead, is connected under cabin floor to
adjuster assembly. Adjuster is a bellcrank
assembly with a knob on the floor for manual
adjustment of pedal position according to pilot
need. Force gradient and control linkage to power
cylinder are connected to a bellcrank on pilot
adjuster.
67.4.4.1 Removal
67.4.4.1.1
Remove pilot seat.
67.4.4.1.2
Remove flight control access
doors.
67.4.4.1.3
Remove nuts, washers and
bolts from control tube (33, Figure 67-5).
Remove control tube (33).
67.4.4.1.4
Remove four bolts attaching
pedal support to bulkhead. Remove pedals and
support.
67.4.4.1.5
Remove nut, washer and bolt
from forward end of control tube (27) and force
gradient (31).
67.4.4.1.6
Remove two bolts and washers.
Remove adjuster knob (33).
67.4.4.1.7 Remove
four nuts, washers and
bolts attaching tail rotor control pedal adjuster
(28) to bulkhead. Remove pedal adjuster (28).
67.4.4.2 Installation
MATERIALS REQUIRED
NUMBER NOMENCLATURE
C-200 Putty
C-201 Primer
67.4.4.2.1
Apply a coat of putty (C-200) to
mounting surface of tail rotor control pedal
adjuster, position on bulkhead, install bolts and
washers. Torque nuts 50 to 70 in.lbs. (5.65 to
7.91 Nm).
67.4.4.2.2
Position adjuster knob (29,
Figure 67-5) in slots of tail rotor control pedal
adjustor, install washers and bolts. Torque 20 to
25 in.Ibs. (2.26 to 2.82 Nm).
67.4.4.2.3
Position forward end of control
tube (27) and force gradient (31) on tail rotor
control adjuster, install bolts, washers and nuts.
Torque nuts 30 to 40 in.lbs. (3.39 to 4.52 Nm)