Aerobatics Made Easy
By JOhn GlezelliS | IllustratIons by FX MoDEls
Flying a Loop with
Two Quarter Rolls
Over the past several years, precision indoor RC aerobatics has become extremely popu- lar. My first indoor competition was at the 2004 Electric Tournament of Champions (ETOC). Pilots performed routines choreo- graphed to music, which is often referred to as aerobatic freestyle. In 2006, in addi- tion to the indoor RC freestyle, U.S. pilots began flying specific sequences (designed
by each competitor) that were performed
in front of flight judges.
If you’re interested in international
indoor routines and individual aerobatic
maneuvers, check out the Great Britain R/C
Aerobatic Association’s website: gbrcaa.
org/ f3pschedules.htm. These indoor RC
sequences include the F3P AP, AF, B, and
C schedules. The maneuver descriptions
are given on the site and there are helpful
videos for newcomers. These class names
may be unfamiliar, but they simply refer
to the level of difficulty; the difficulty
increases in each class and goes from F3P C
to the F3P AP and AF categories.
The 2012-2013 preliminary schedule for
the most advanced indoor competition
(F3P-AP- 13 class), contains a maneuver
that builds on some of the fundamentals of
loop variations we’ve discussed in previous
columns. Maneuver 7 in this category is a
loop with two quarter rolls performed in
opposite directions. While this may seem
simple, the maneuver is rather complex
and difficult to execute properly.
Even though this maneuver is intended
for indoor precision aerobatic competition, the setup process for both an indoor
aircraft and an outdoor park flyer are
similar.
Setup
Since we are talking about an indoor
aerobatic maneuver, I thought it would
be helpful to cover both indoor and park
flyer setup. For my indoor 32-inch-span
airplanes that weigh about four and a half
ounces, I prefer to use maximum rates at
all times. Control throws are 45 degrees for
aileron, elevator, and rudder deflections
(active all the time), with about 65% expo-
nential across the board. Generally, when
you fly indoors, your plane has to perform
in a rather confined space. Gymnasium and
other indoor sports complexes have differ-
ent obstacles with which to contend. Since
indoor airplanes are extremely lightweight,
their flight characteristics are much differ-
ent than larger electric and gas-powered
designs. In fact, indoor flyers are relatively
docile—even with such extreme control
surface deflections! While flying indoors,
maneuvers happen rather quickly. As a
result, I change the exponential amount
so that the aircraft is smooth whenever the
control sticks are around center, but maxi-
mum rates are present when having to per-
form a snap roll or a spin.
Overview
During this maneuver, the aircraft should
be flown parallel to the runway and
upwind—unless it is indoors! You should
initiate the loop by pulling back on the
elevator control stick as soon as the aircraft
is directly in front of yourself (known as
the center position). Since the maneuver
must be round, the initial pull that starts
the maneuver determines the size loop.
A more gradual pull results in a larger
maneuver and an aggressive pull results
in a smaller loop. The two quarter rolls
are performed at the top of the maneuver. The first quarter roll begins at the “ 10
o’clock” position with the model in knife-edge flight at the top. The second quarter roll (in the opposite direction) begins
immediately after the first roll and it ends
at the “2 o’clock” position. The entry and
exit point altitudes must be the same, and
it is important to regulate throttle input to
balance the maneuver.
Steps to success
StEp 1: This maneuver starts and exits
directly in front of the pilot. Aligning the
airplane, head into the wind, upright, parallel to the runway, approaching the center
position. For this example, the aircraft is
traveling from right to left. Advance the
throttle to 80% and begin to pull elevator
as soon as the airplane is directly in front
of you. A gradual pull is best.
