Piper Arrow IV, Maintenance Manual

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GENERAL.
STABILATOR.
REMOVAL AND INSTALLATION OF STABILATOR. (Refer to Figure 55-1.)
The stabilator assembly can be removed by following the procedure given below.
1. Remove the fin tip attachment screws and disconnect the light at quick disconnect, then remove tip
assembly.
2. Disconnect trim push rod and push rod attached to stabilator balance weight arm.
3. Remove balance weight arm from stabilator by removing attachment bolt at the forward and aft arm
mounting fitting.
4. Remove the two hinge bolts at the pivot points and remove the stabilator.
5. Reinstall the stabilator in reverse of removal instructions.
6. Check attaching hardware for proper installation.
REMOVAL AND INSTALLATION OF STABILATOR TRIM TAB. (Refer to Figure 55-1.)
The trim tab can be removed by following the instructions given below.
1. Disconnect the trim push rod from the trim horn.
2. Remove the hinge pins and remove the trim tab.
3. Reinstall the trim tab in reverse of removal instructions, with new hinge pins.
BALANCING EQUIPMENT.
The balancing must be done using a suitable tool capable of measuring unbalance in inch-pounds from the
center line of the control surface hinge line. A suggested tool configuration is shown in Chapter 95. Other tool
configurations may be used, provided accuracy is maintained and recalibration capability is provided. The tool
shown may be calibrated by placing it on the control surface to be balanced with the balance points over the
control surface hinge center line and balance bar parallel to the chord line. Position the trailing edge support on
the tool to align the tool with the control surface chord line and secure it in this position. Remove the tool
without disturbing the trailing edge support and balance the tool by adding weight to the light end as required.
(The movable weight must be at the center line.) Place the tool on the control surface perpendicular to the
hinge center line as shown in Figure 55-2. Read the scale when the bubble level has been centered by
adjustment of the movable weight.
BALANCING STABILATOR. (Refer to Figure 55-2.)
To balance the stabilator, the assembly must be complete including the trim tab, the tab push rod and end
bearing, stabilator tips and all attaching screws. Before balancing, tape the trim tab in neutral position with a
small piece of tape. Place the complete assembly on the knife edge supports in a draft free area in a manner
that allows unrestricted movement. Place the tool on the stabilator with the beam perpendicular to the hinge
center line. Do not place the tool on the trim tab. Calibrate the tool as described in previous paragraph. Read
the scale when the bubble level has been centered by adjustment of the movable weight and determine the
static balance limit. If the static balance is not within the limits given, proceed as follows:
55-20-04
Page 55-01
December 1, 1978
2J12
PIPER AIRCRAFT
PA-28RT-201 / 201T
MAINTENANCE MANUAL