Radio Control Scale Aerobatics
John Glezellis
The Aresti aerobatic-maneuver diagramming system is explained
In the October column I touched on my background in this fine sport as well as the benefits of flying in aerobatic competition. In addition I covered a few critical mixes that will assist you in becoming a better pilot (such as the need to use both rudder-to-elevator and rudder-to-aileron mixes).
As promised in the first column, I will break down each maneuver in the 2007 IMAC Basic category and help you, the reader, better understand the language of aerobatics, which is called Aresti.
A short history lesson: in 1961 Colonel Jose Luis de Aresti Aguirre published his system of diagramming aerobatic figures (known as his Sistema Aresti). When aerobatic pilots compete at the international level, a common language is needed for aerobatic figures; that language is called "Aresti."
The 2007 Basic program is:
- Roll
- Humpty Bump with a half roll on the down-line
- Reverse Sharks Tooth with a half roll on the 45° up-line
- Reverse Teardrop
- Hammerhead
- Loop
- Half Cuban 8
- Sharks Tooth with a half roll on the 45° down-line
- Immelmann
- 1½ turn upright spin to upright exit
Let's begin with the first maneuver. When you look at the list (as shown in the language of Aresti), you might notice that it is broken up into three sections: maneuvers that will be performed to the left side of the aerobatic box, the center of the box, and the right of the box.
In the language of Aresti a maneuver begins with a solid circle, whereas the end of the maneuver ends with a vertical line. In addition, each maneuver is numbered (which determines the order in which the maneuvers are to be flown). A solid line represents upright flight; a dashed line represents inverted flight/lines.
- The Roll
The 2007 Basic sequence begins with a roll from upright level flight. In Aresti a roll is represented by an arched line (with a small triangle at the top). A single roll's direction (to perform it to the right or to the left) is up to the pilot to decide. To obtain the best possible score regarding positioning, this maneuver should be centered within the aerobatic box. That means the model should be inverted when it is directly in front of the pilot (and the judges). Also, the roll rate should be constant throughout the maneuver.
- The Humpty Bump
The maneuver, in this case, is flown at the end of the aerobatic box. It is a turnaround maneuver. For this Humpty Bump the pilot will fly the model to the end of the aerobatic box and pull to a vertical up-line. Then the pilot must pull half of an inside loop (as the loop radius is solid, which means that it is a pull) to establish a vertical down-line. On the vertical down-line, the pilot must perform a half roll (which is to be centered on the down-line segment). In the Basic class there is a half arc (with a triangle) that comes in contact with the vertical down-line. This means the pilot must perform a half roll on the vertical down-line segment of the Humpty Bump.
The traditional Sharks Tooth starts with a pull or a push to a vertical up-line. Then the pilot performs a pull (or a push) to a 45° down-line. Last, the pilot will perform a pull or a push to level flight (at the same altitude at which the maneuver began).
A Reverse Sharks Tooth is slightly different. In the 2007 Basic sequence, at the start of the maneuver the pilot will pull to a 45° up-line. Then at the center of this 45° up-line, he or she will perform a half roll to an inverted 45° climb. Then the pilot will pull to a vertical down-line. Last, the pilot performs a one-quarter loop to upright, level flight.
- Teardrop
In the Basic class no roll is performed on the up-line or the 45° down-line portion of the maneuver. However, in higher classes expect to see snap rolls, rolls, or both on both line segments.
To fly this maneuver, pull to a vertical up-line from upright level flight. Then pull five-eighths of an inside loop to a 45° down-line. Last, pull to upright level flight (at the same altitude at which you began the maneuver).
For perfect centering the model should be flown past center before the maneuver is begun. Then the model should approach the pilot's center as it is inverted (throughout the five-eighths inside-loop portion of the maneuver).
- Hammerhead
In aerobatics this is the same maneuver as the Stall Turn. In Aresti it is drawn as a vertical up-line and down-line with an angled line at the top.
Although the Tailslide (in Aresti) looks similar, it differs at the top. Rather than having one line represent the up- and down-line (with an angled line at the top), it has two lines representing the up- and down-line that are connected by two arched lines which determine the direction of the flop, which can be either wheels up or wheels down.
Next time I will cover a few more maneuvers from the 2007 Basic sequence. In addition, I will briefly cover my experience at the 2007 European Extreme Flight Championships; by that time I will have traveled "across the pond" to the Czech Republic.
Until next time, fly hard! MA
Sources
- International Miniature Aerobatic Club
- Box 1010
- King, NC 27021
- www.mini-iac.com
Transcribed from original scans by AI. Minor OCR errors may remain.
