Piper Cherokee Six Service Manual page 143

PIPER CHEROKEE SIX SERVICE MANUAL
4-30. CONTROL SURFACE BALANCING.
4-31. CHECKING CONTROL SURFACE BALANCE. The movable control surfaces have
been statically balanced at the time of installation at the factory and normally should not
require rebalancing. Where possible the control surfaces were set with the balance weight on
the heavy side of the limits, to permit limited repair or paint touch-up without adjusting the
balance weight. It should be noted however, that spare control surfaces are delivered
unpainted and the static balance will not necessarily fall within the limits provided, this is more
pronounced on the stabilators and rudders. The completed control surface including paint
should be within the limits given in Table IV-II. If the surface is not to be painted, the balance
weight will probably require adjustment. All replacement control surfaces or surfaces that
have been repainted or repaired should be rebalanced according to the procedures given in
paragraphs 4-33 thru 4-35. The static balance of the surfaces must be as specified in Table IV-
II.
Before balancing any control surface, it must be complete including tip, trim/servo tabs
as applicable and tab actuating arms or push rods with bearings as applicable, and all
optional equipment which is mounted on or in the control surface when it is flown,
including paint, position lights and wiring, static wicks, scuff boots, etc.
If optional equipment is added or removed after balancing the control surface must be
rebalanced. During balancing, trim/servo tabs must be maintained in their neutral positions.
4-32.
CHECKING CONTROL SURFACES FREE PLAY. The following checks are
recommended before balancing to ascertain the amount of "free play" in the stabilator,
stabilator trim tab and aileron:
a. Stabilator: Check the stabilator for any "free play" at its attachment points by
grasping each half near the tip and gently trying to move it up and down, fore and aft, and
in and out. No play is allowed.
b. Stabilator Trim Tab: Set the stabilator trim tab in neutral position. This neutral
position is determined with the airplane properly rigged per instructions given in Section V
of this Service Manual and the trim indicator at its neutral position. Obtain a straightedge
long enough to extend from the ground up to a few inches above the trim tab trailing edge.
Place the straightedge next to the trim tab inboard (center) trailing edge; secure the
stabilator in neutral and grasping the tab, gently move it up and down, mark the limit of tab
free play on the straightedge. The overall travel (free play) must not exceed 0.15 of an inch.
The use of a dial indicator and fixed stand is recommended.
c. Aileron: Set the aileron in its neutral position and secure. Obtain a straightedge long
enough to extend from the ground up to a few inches above the aileron trailing edge. Place
the straightedge next to the aileron trailing edge and gently move the aileron up and down,
mark the limit of travel (free play) on the straightedge. The overall travel (free play) must
not exceed 0.24 of an inch. Should free play exceed the limit stated make necessary repairs
as required to eliminate excessive free play. Grasp the aileron and move it spanwise
(inboard/Outboard) to insure maximum end play of .035. is not exceeded.
STRUCTURE
Revised: 12/4/79
IF23