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© 2005 Stevens AeroModel all rights reserved.
This guide is offered as an addendum to the original Squirt Flight Guide and is intended to smooth out your transition to
the new aileron wing for your Squirt. Good luck and have fun!
Transition to Ailerons
The primary difference between flying a R/E/T equipped model and an aileron-equipped model is not that one has
ailerons for roll control and one doesn’t, but rather that the aileron-equipped model has, inherently, less overall roll
stability. This is primarily due to the lack of dihedral on the aileron-equipped model. This will provide a small challenge
when transitioning to an aileron-equipped model, as the model will have significantly less self-righting tendencies. You’ll
be forced to make corrections in roll that would have normally been self-correcting in your R/E/T trainer. To me, the
transition to an A/E/R/T model is not a significant one. Where it becomes challenging is when a pilot makes the transition
to a
fast
model (think a P-51 or Spitfire) or one with a high wing loading (think heavy weight with a small wing) as their
first aileron model. The transition to an aileron-equipped model is challenging enough without adding the additional speed
and agility of a high performance aileron model to the learning process. A more acceptable transition would be from an
R/E/T trainer, to an A/E/R/T aileron trainer, then on to a Warbird or other faster aileron model. Your decision to purchase
an aileron wing for your Squirt is a good one!
From a “flying the plane” point of view, ailerons present several changes to your maneuvering. With ailerons, we’ve split
roll control from yaw control. The ailerons control the roll of the airplane, while the rudder controls the yaw. Turns, as a
result of the decreased dihedral, are a full four-channel exercise. Coordinated turns now require additional control inputs
on the rudder as well as the ailerons to counter adverse yaw.
Adverse Yaw
There are two different kinds of drag that are important to understand, Parasite and Induced. Parasite drag occurs as a
result of pulling objects like the landing gear, antenna, and control linkages through the air and is directly related to the
speed of the aircraft. The faster the airspeed, the higher the parasite drag. The second drag, induced drag, is a by-
product of creating lift. Anytime we create additional lift, we create additional induced drag.
Adverse yaw is a direct result of induced drag. For this example, we’ll initiate a roll into a left turn. When we initiate the
left turn, the left aileron deflects above the wing and the right aileron deflects below the wing. For all practical purposes,
we decrease the lift on the left wing allowing it to drop, and increase the lift on the right wing causing it to be raised. As a
result of increasing the lift on the right wing, the drag is increased on the right side of the airframe. The by-product of that
increase in drag on the right wing is a yaw to the right (opposite the direction of roll). To counter adverse yaw, simply
apply rudder in the direction of the turn...i.e., left turn - left aileron - left rudder. A coordinated turn is one that has been
corrected for adverse yaw. A little later on we’ll discuss some exercises to improve your turn coordination.