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flight is to hold the airplane vertically and advance
the throttle to full power. The static thrust should be
enough to make the airplane accelerate vertically
from a standstill.
Many people also consider the proverbial “aft”
center of gravity (CG) to be crucial to hovering
success. Through much experimentation on many
types of models, we have found that neither a very
forward or very aft CG is beneficial to hovering
flight. In fact, given sufficient control surface
movement, softened correctly with exponential
throws, one can hover controllably over a large
range of CG positions. The center of gravity is even
more critical on the Tensor because it is capable
of producing substantial force (lift) both up-and-
down and side-to-side. In other words a single
CG position must provide both longitudinal and
directional stability.
This brings us to the most important aspect of 3D
setup—control surface deflection. Do you need
large amounts of deflection to hover? The truth
is you do not. During the perfect hover or torque
roll you barely move the surfaces off their neutral
position. It is not until you get the airplane in an
attitude far enough from vertical that you need to
delve into your large reserves of control surface
throw and excess power. You will find that having
45–60 degrees of throw is very beneficial to your
success in 3D flight. Typically, the most throw you
can mechanically achieve is what you should use.
Set up the airplane such that maximum throw
is obtained by placing the pushrod the farthest
hole out on the servo and the hole closest to the
control surface on the control horn. While this is
not standard or recommended practice on a larger
airplane because of the potential of flutter, this type
of setup works quite well on the aerobatic indoor
electric models.
