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Set-up and trimming
The center of gravity range for the 74 inch Laser EXP begins at 5” from the leading edge
of the wing measured at the root and extends back to 6”. CG is determined with the Laser
in the upright position. One of the best ways to dial in the proper CG for your aircraft is
the 45 degree line test. Fly the aircraft in front of you from left to right (or right to left if
you prefer) at full throttle. Pull the aircraft into a 45 degree up line and establish this line.
Roll the aircraft inverted, neutralize the elevator and pay close attention to what the plane
does. Ideally the plane will continue on this line for several hundred feet before it starts to
slowly level off. If the airplane immediately drops the nose and dives toward the ground it
is nose heavy. If it begins to climb inverted toward the gear it is tail heavy. There is no
need to have the Laser excessively tail heavy to perform 3D maneuvers. At this time you
will also want to balance your plane laterally. Add a small amount of weight to the wingtip
to achieve proper lateral balance.
Control surface throws
I highly recommend that you purchase a throw meter that measure in degrees. There are
several units available commercially. These units are a great aid in set-up and definitely
beat the “that looks about right” method. The following control surface travels are what I
use on my own Laser and are a good starting point but are by no means the only way to
set up the aircraft. Start here and then adjust to fit your own preferences and style of
flying.
Elevator: 8-10 degrees low rate, 18-20% exponential; all you can get high rate, 60-65%
exponential
Aileron: 20 degrees low rate, 30-40% exponential; 38 degrees high rate, 65-70%
exponential
Rudder: 20 degrees low rate, 50% exponential; all you can get for high rate, 80-90%
exponential.
Again, this is just a starting point. Adjust to your liking.
