Great Planes P-51D Mustang 40 Kit - GPMA0175 - Manual (Page 49)

FLIGHT TRIMMING CHART
TRIM FEATURE MANEUVERS OBSERVATIONS CORRECTIONS
CONTROL
CENTERING
CONTROL
THROWS
ENGINE
THRUST
ANGLE
1
CENTER OF
GRAVITY
LONGITUDINAL
BALANCE
Fly general circles and
random maneuvers.
Random maneuvers.
From straight flight,
chop throttle quickly.
From level flight roll to
45-degree bank and
neutralize controls.
Try for hands off straight and
level flight.
A. Too sensitive, jerky
controls
B. Not sufficient control
A Aircraft continues level
path for short distance.
B. Plane pitches nose up
C. Plane pitches nose down.
A Continues in bank for
moderate distance.
B Nose pitches up
C Nose drops.
Readjust linkages so that
Tx trims are centered.
If A, change linkages to
reduce throws
If B, increase throws.
If A, trim is okay.
If B, decrease downthrust.
If C, increase downthrust.
If A, trim is good.
If B, add nose weight.
If C, remove nose weight.
SPLIT ELEVATORS
(Also Yaw and
C.G.) Into wind, pull open
loops, using only elevator
Repeat tests doing outside
loops to inverted entry. A. Wings are level throughout
B. Plane tends toward outside
when right side up, and to
inside when inverted
C Plane goes in on regular
loops and out on inverted.
D Plane goes out on both
types of loops
E Plane goes in on both
types of loops
If A, trim is "fine
If B, add weight to right
wing, or add right rudder.
If C, add weight to left
wing, or add left rudder.
If D, raise right half of
elevator (or lower left).
If E, raise left half of
elevator (or lower right).
YAW Into wind, do open loops,
using only elevator.
Repeat tests doing
outside loops from
inverted entry
A Wings are level throughout.
B Yaws to right in both
inside and outside loops.
C Yaws to left in both
inside and outside loops
D Yaws right on insides, and
left on outside loops
E Yaws left on insides, and
right on outside loops
If A, trim is correct
If B, add left rudder trim
If C, add right rudder trim
If D, add left aileron trim.
If E, add right aileron trim.
LATERAL
BALANCE
climbs into Hammerheads
Do same from inverted
C Falls off to right in both
AILERON
RIGGING
neutralize controls.
C Nose tends to go to
WING
INCIDENCE
B Model veers in nose
Into wind, do tight inside
loops, or make straight up
entry
With wings level, pull
to vertical climb and
Knife edge flight.
A. Wings are level and plane
falls to either side
randomly in Hammerhead.
B Falls off to left in both
inside and outside loops.
Worsens as loops lighten
loops Worsens as loops
tighten
D Falls off in opposite
directions on inside
and outside loops
A Climb continues along
same path.
B Nose tends to go to
inside loop
outside loop
A Models tends to veer
in nose up direction
down direction
If A, trim is correct.
If B, add weight to right
wing tip
If C, add weight to left
wing tip.
If D, change aileron trim 3
If A, trim is correct
If B, raise both ailerons
very slightly
If C, lower both ailerons
very slightly
If A, reduce wing incidence.
If B, increase wing incidence.
1. Engine thrust angle and C G interact Check both
2. Yaw and lateral balance produce similar symptoms Note that fin may be crooked Right and left references are from
the plane's vantage point
3. Ailerons cannot always be trimmed without sealing the hinge gap.