53 sailplane trimming chart – HITEC Eclipse 7 Pro User Manual
Page 55

53
SAILPLANE TRIMMING CHART
To test for
Test Procedure
Observations
Adjustments
1. Model Control Neutrals
Fly the model straight and
level
Adjust the transmitter trims for
hands-off straight & level flight,
no camber control.
Change electronic subtrims
and/or adjust clevises to center
transmitter trims.
2. Control Throws
Note: be sure all aileron &
flap horn pairs have
matching angles
Fly the model and apply
full deflection of each
control in turn. Camber
control in neutral (setup
6 & 9).
Check the model’s response to
each control input. Set flaps for
as much down flap as possible in
glide path control (90 is good)
<5 reflex needed.
Aileron & elevator rates: set for
desired authority
Rudder: set for max. throw
Set flap motions in Steps
4, 5, & 9.
3. Decalage & Center of
Gravity
(Note: this is a trial and
error test procedure,
depends on desired
handling characteristics.
Back CG = less stability
but better performance)
Trim for level glide.
Enter 45 dive (across
wind if any) and release
controls. CAUTION:
beware of airspeed &
flutter.
A. Does the model continue its
dive without pulling out or diving?
B. Does the model start to pull
out
(nose up)?
C. Does the model start to tuck
(dive more nose down)?
A. No adjustment
B. Reduce incidence (add down
elevator) and/or reduce nose
weight
C. Increase incidence (add up
elevator or add nose weight)
4. Glide Path Control
Settings - Pitch Trim
Note: be sure all aileron &
flap horn pairs have
matching angles.
Fly the model and slowly
apply full deflection of
glide path control (airbrake
stick). Observe any pitch
changes.
A. Nose drops, up elevator
required for level flight
B. No pitch change
C. Tail drops, down elevator
required to maintain level flight
A. Several options:
1) more up elevator mix;
2) reduce aileron reflex*;
3) increase flap motion*
B. No adjustment
C. Reverse of A
5. Glide Path Control
Settings - Elevator Delays
Rapidly apply full glide
path, observe initial
pitching response
A. Nose drops
B. No pitch change
C. Nose rises
A. Increase elevator delay %
B. No adjustment
C. Reverse of A
6. Glide Path Control
Settings - Roll Response
Fly the model and apply
full glide path control.
Observe any roll motion.
A. Model rolls to right when glide
path control (airbrake stick)
activated
B. No roll motion
C. Model rolls to left
A. Mix in less right & more left
aileron reflex with airbrake
motion
B. No adjustment
C. Reverse of A
7. Differential/Coupled
Rudder setting
Fly the model and apply
alternating left & right
aileron commands.
Observe path of fuselage
line.
A. Model yaws to right with left
aileron and vice versa
B. Fuselage traces straight line
C. Model yaws to left with left
aileron and vice versa
A. Increase differential and/or
amount of rudder coupling
B. No adjustment
C. Reduce differential and/or
amount of rudder coupling
8. Camber (full wing aileron
& flap droop or reflex)
setting
Put the model in a straight
glide passing in front of you.
Apply camber control.
A. Model slows down & stalls or
sinks rapidly
B. Model slows slightly
C. Model speed unchanged
A. Reduce amount of droop &/or
add elevator compensation
B. No change needed
C. Reverse of A
9. Launch Settings (Part 1)
Switch to Launch mode.
Launch the model &
observe climb angle and
required control inputs
A. Shallow climb angle; lots of up
elevator required
B. Model climbs steeply with little
control input needed
C. Too steep climb, weaves
back & forth, down elev. required
A. Move towhook rearwards
small
amount, increase up elevator
preset a little, or add camber
B. No adjustment
C. Reverse of A
10. Launch Settings (Part 2)
Switch to Launch mode.
Launch the model &
observe climb angle and
required control inputs
A. Model banks left on tow
B. Model climbs straight ahead
with
no roll input needed
C. Model banks right on tow
D. Model tip stalls to one side
A. Reduce left ail & flap droop or
increase right ail / flap droop
B. No adjustment
C. Reverse of A above
D. Check droop same on both
sides.
Increase aileron or decrease flap
droop
11. Speed Settings
Switch to speed mode
(entire TE reflexed slightly,
<1/16”/1 mm)
A. Nose drops
B. No pitch change
C. Tail drops
A. Increase up elevator preset
B. No adjustment
C. Reverse of A
12. Elevator-to-Camber
Coupling Setting
Fly model at high speed,
bank & pull up
A. Model keeps speed and
comes about rapidly
B. Model slows down
A. Increase down flap or leave
alone
B. Reduce amount of down flap
*Note: Swept wing planeform may cause opposite reactions, so experiment until proper behavior is attained.