Piper Navajo PA-31 Service Manual page 249

PIPER NAVAJO SERVICE MANUAL
c. Install the spreader bushing with one washer between each mounting bracket and bushing. Install
the through bolt and secure.
d.
If working with the left transmission (7). connect the flexible actuator shaft (6) and safety with
MS20995-C41 safety wire. Attach the right flexible shaft (4) during rigging and adjustment.
e. Check the flap rigging and adjustment per instructions given in this section.
f. Install access plate.
5-84. RIGGING
AND ADJUSTMENT OF CALCO FLAP SYSTEM.
PPS50035-1.L
H-2091
Following are definitions of terms used in the description and service information presented in the
following paragraphs:
RC - Control Rheostat Wiper
RL - Left Wing Flap Rheostat Wiper
RR - Right Wing Flap Rheostat Wiper
VC - Voltage at RC (Control)
VL - Voltage at RL (Left Flap)
VR -
Voltage at RR (Right Flap)
VCL - Voltage difference between VC & VL at flap-up position.
VCR - Voltage difference between VC & VR at flap-up position.
VCR -
Voltage difference between RL & RR
RT2- Amplifier Trimmer Adjustment - Left
RT3 - Amplifier Trimmer Adjustment - Right
VC - VC + (.10 + .10 -.05)
The Control rheostat operated by the Flap Selector will be referred to throughout this rigging procedure
as RC (rheostat control). The wing flap rheostats will be designate as RL (rheostat left) and RR (rheostat
right). The voltages present or read at the center taps will be referred to as VC VL and VR respectively
a. Proper operation requires that the rheostat (RL) on the left flap respond to any changes in the flap
position selector rheostat (RC) in the form of VL and VC. It follows that the amount of stroke travel, as well
as how it is centered with respect to the ends. will be determined by how RL is adjusted relative to RC. Since
VC is fixed and cannot be changed. a trimmer pot RT2 is provided in the control amplifier to allow adjustment
of VL to agree with VC.
b. Throughout all of the adjustment procedures it is important that. whatever changes are made to RL
and RT2. must also be made to RR and RT3. It is the function of RR to track RL over the entire stroke range
and shut the system OFF if the outputs in the form of VLand VR deviate by more than 0.55 olts. This voltage
differential (
) corresponds to a five degree asymmetrical flap condition. An additional function of RR is
to provide a voltage input to the control amplifier in order to provide an output to the flap position indicator
NOTE
In general. the adjustments of RL. RR. RT2 and RT3 are always
made with the flaps in the DOWN position and the magnitude of
these adjustments will be based on the values of VC. VL and VR
measured with flaps in the UP position.
WARNING
All adjustments must be made with the motor power off.
Revised: 10/12/83
SURFACE CONTROLS
Effectivity
CALCO 1K9