you will agree it was time well spent. One of the most practical ways to check the CG on
an aircraft this size is to insert the carbon fiber wing tube into its sleeve in the fuselage
and tie a length of rope around the tube on each side of the fuselage, forming a loop that
you can pick the aircraft up with. Slide the wings into position, install the canopy and pick
up the plane with the rope. The MXS should balance in a horizontal position. Move your
batteries and radio equipment to achieve this condition. This will give you a safe starting
place for the first flights. One of the best ways to fine tune the 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 MXS 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 light
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. For any type of precision flying, surfaces that
travel equal distances are a must. The following control surface travels are what I use on
my own MXS. These are a good starting point, but are by no means the only way to set up
the MXS. Start here and then adjust to fit your own preferences and style of flying.
Elevator:
8-10 degrees low rate, 20% exponential; all you can get high rate,
60-65% exponential
Aileron:
20 degrees low rate, 30-40% exponential; all you can get high rate,
65-70% exponential
Rudder:
20 degrees low rate, 50% exponential; all you can get for high rate, 80-90%
exponential.
This completes the assembly of the 94 inch MXS. As a final step clean the entire aircraft
with glass cleaner, then apply a coat of spray-on wax and buff the finish to a high gloss.
My favorite product for this is Eagle One Wet Wax AS-U-DRY, available in the
automotive section of most Wal-Marts, K-marts, Sears, Targets, etc. People often ask me
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