One Of the fastest-growing Radio
Control (RC) competitions is Precision
Aerobatics—primarily IMAC (International
Miniature Aerobatic Club) events.
A large number of new IMAC pilots have
been in the hobby for several years, and are
attracted to the new challenge of precision flight.
The majority of these pilots are entry level, but
IMAC has also attracted pilots with experience in
other RC competitions—primarily AMA Pattern.
Pattern and IMAC develop similar skills,
so it is not surprising to see a bridge between
the two. A competitor who is interested in
Pattern should be encouraged to try IMAC,
and the other way around.
Even at upper levels, many of the top
IMAC, Tournament of Champions (TOC), and
Masters pilots are active in Pattern and IMAC.
Eric Henderson—my counterpart who
writes the “Radio Control Aerobatics”
column— listed several good entry-level
airplanes for Pattern. Several of the models on
his list sell for less than $300—far less than
most two-meter Pattern airplanes or 35%
IMAC airplanes. Those airplanes would also
be good for IMAC.
Only the three upper classes in IMAC have a
Scale requirement, so a nonscale airplane can be
flown at an IMAC event. Popular Almost Ready
to Flys (ARFs), such as the Hangar 9 CAP 232
or the Sig CAP 231EX, are good entry-level
IMAC airplanes—and there are plenty of others.
IMAC also encourages larger airplanes,
so it’s common to see a diversity of sizes in
the lower class.
IMAC has four classes: Basic,
Sportsman, Advanced, and Unlimited. The
class titles are the same as those used in fullscale
aerobatic competition.
The maneuvers and sequences flown in
IMAC are modified versions of the annually
published full-scale competition sequences.
The schedules are written using “Aresti”—a
visual language that describes each maneuver
with symbols; there is no written text.
The judging criteria for IMAC is based on
the Federation Aeronautique Internationale
(FAI) catalog of “figures,” also derived from
full-scale aerobatics. The FAI catalog is
broken into eight sections—each called a
“Family”—and each Family has its own rules
of construction and scoring criteria. All figures
in the catalog are written in Aresti.
The AMA rule book, Competition
Regulations, contains a short Aresti review and
Family descriptions under the IMAC “Flying
and Judging School” section. Reading the
Family descriptions is critical in understanding
IMAC scoring—as a competitor or as a judge.
The AMA rule book is available from
AMA Headquarters.
Paul Kopp, 1013 S. Sedona Ln., Anaheim CA 92808
RADIO CONTROL SCALE AEROBATICS
One of the most successful and best-flying airplanes in its size range: the Carl
Goldberg Models Extra 300. Brian Copfer’s has an MVVS 1.2 twin and APC prop.
Ken Kuzubinski’s lightened Ohio Models Extra 300. The model has an 87-inch
wingspan, a BME 2.7 engine, a Mejzlik propeller, and weighs 15 pounds.
Booker Washington and beautiful Midwest Extra 300XS. Has Moki 2.1, Zinger prop.
January 2001 129
two questions new competitors frequently
ask are what to expect at a contest and how
to be a successful competitor.
A typical two-day IMAC contest features
two days of “Known” sequences, one round
of “Unknowns”—usually flown on the second
day—and one or two days of “Freestyle.”
The Knowns are sequences published
annually by IMAC, with increasing
difficulty by class; “Unlimited” is the most
difficult. (The TOC and Masters sequences
are Unlimited in difficulty).
Part of the attraction to IMAC is the
challenge of the Unknowns, which are flown
in the three upper classes—not in Basic class.
Unlike the Knowns, which are changed
annually, Unknowns are written specifically
for each event, and are unseen by the pilots
until the day before they are flown. No
practice of Unknowns is permitted.
Although the Known and Unknown
sequences rely on specific scoring criteria,
Freestyle judging is subjective. The winning
pilots are usually the ones who combine
their creativity with precision flying.
Some Freestyle maneuvers defy
definition, but they explore the outer limits
of the airplane’s capabilities—and
sometimes the pilot’s nerves!
3-D (three-dimensional) maneuvers such as
Torque Rolls, Waterfalls, Pinwheels, Blenders,
and Elevators are not individually judged, but
are often used as components of a pilot’s
sequence. A one-dimensional Freestyle routine
will not score well; the pilot must be versatile.
Freestyle is a separate event, and is
scored independently of the Knowns and
Unknowns. (IMAC is unlike the TOC and
the Masters, which both incorporate
Freestyle into the competitor’s score.)
Freestyle is also a spectator’s event, and
people are consistently awed by the ability
of the better Freestyle pilots.
What skills are needed to succeed?
Pilots who come from other judged
competitions usually have an advantage,
although the reason has nothing to do with
their flying skills. The advantage is that they
have experienced “being judged.”
The pilot who wins consistently may not
be the “best” pilot, but he or she probably is
the best listener. That pilot’s scores will
reflect how well he or she is able to
incorporate the judges’ comments into his or
her flying.
Judges are the best source of feedback
for how to improve or win, and they are
often overlooked.
The fliers who use judges as a resource
are usually at the top of the class, or they get
there in a hurry. Pilots who retrieve their
score sheets without question tend not to
improve, but perfect the same mistakes.
A pilot without a background in scored
competition might still score well, but the
Jon Ridpath poses with two of Doug Lee’s (DL Designs) Edge 540s. One is powered by
a .60 engine; the other, with the 77-inch wingspan, is powered by a 1.8.
January 2001 131
flier who has been judged will be higher on
the learning curve.
All maneuvers start with 10 points, and
are downgraded for each error of pitch,
yaw, or roll. One method of improving
scores is to fly using a judge’s perspective,
rather than your own as a pilot.
Judging makes the pilot more aware of
his or her own mistakes. It also requires that
the pilot learn the criteria for each figure and
consistently fly against that standard.
One trap many competitors fall into is
relying on other pilots for guidance, instead
of reading the rules and learning the criteria.
It helps to have a second set of eyes
critiquing the flying, but the pilot has to be
familiar with the figure and the scoring.
Prior to a pilot’s first competition, he or
she should go through the sequence maneuver
by maneuver, and learn the criteria for each
one. As simple as that sounds, the majority of
entry-level competitors don’t do it—and their
scores reflect the lack of preparation.
The difference between first and fifth
place may be a simple correction, but the
pilot’s scores will not improve without a
good understanding of what the figure is
supposed to look like.
Many entry-level figures sound
deceptively simple, but the maneuver has to
be flown with little or no error to score high—
regardless of how simple or complex it is.
Many judges are easier on entry-level pilots
and focus only on obvious errors. Conversely,
mistakes that might have been ignored in Basic
will be downgraded in the upper classes.
A perfect figure will receive a 10, but
that score is few and far between in front of
a good judge, as are pilots who can
consistently fly them.
A vital practice tool is a “stick” plane, to
give a pilot a visual representation of the
maneuver. A stick airplane can be something
as simple as a business card stuck across a
pen, or a small model of the pilot’s model,
MonoKote®d and complete with graphics.
An experienced judge usually tries to
answer questions by using a stick airplane,
rather than relying on a verbal explanation.
As part of their preparation for Unknown,
pilots “fly” the sequences with stick airplanes.
Prior to the scored competition, many
contests will have a pilot demonstrate the
Unknowns using one of these tiny models,
focusing on specific judging elements and
answering questions from competitors.
Another component of success is the
pilot’s choice of airplane.
A popular myth is that a big airplane is
needed to win in any of the classes. A
Giant Scale (80-inch or larger wingspan)
airplane is beneficial in the Advanced and
Unlimited classes, but it is not necessary in
the lower classes. Plenty of competitors
who fly smaller airplanes consistently win
against larger hardware.
The trick is plenty of practice—not
much of a trick. Big airplanes “present”
well and they are predictable, but they are
not a formula for success. What’s
important is that whatever you fly flies
straight.
Competition is a hostile environment
for an airplane that corkscrews in loops,
requires constant corrections, or otherwise
won’t hold a straight line. If the airplane is
crooked, it doesn’t matter how big it is.
Precision Aerobatics requires patience
and discipline, but virtually everyone who
tries it states that his or her flying skills
improve.
Initially, trying to fly a straight line may
be like trying to balance a basketball on a
screwdriver. However, as the pilot becomes
more comfortable with the figures, and the
airplane setup is optimized for competition,
the pilot experiences the rewards.
Until next time, 10s. MA
