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Aerobatic Maneuvers – Part 3 (Avalanche)

This is the basic loop with a roll (usually a snap roll) at the top of the loop.

Avalanche
Avalanche

The roll has to be centered at the top of the loop.

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Aerobatic Maneuvers – Part 1 (Rolls)

April 30, 2010 Leave a comment

Tired of flying straight & level ?  I’ll describe in detail all of the wildest aerobatic maneuvers for you to try!

This will be a list of aerobatic figures that have common names. Some of these were invented during aerial combat in World War I. I have also included a short verbal description and the IAC symbol for each basic figure.

The symbols for the figures follow the rules of the FAI for depicting aerobatic figures. The figure starts at the small solid circle and ends at the vertical bar. All aerobatics figures start and end from horizontal lines in either upright or inverted flight. In aerobatics competition, most figures can be entered and/or exited from either upright or inverted flight. This affects the difficulty numbers for the figures. In general, the altitude at which the figure is entered does not have to be the same as the exit altitude. Exceptions are for instance the Cuban Eight, all full loops (regular loop, square loop, etc). In cases where the entry and exit lines have to be the same altitude, they are drawn slightly separated to better show them.

The elements used in these figures are horizontal, vertical and 45 degree lines. These describe straight flight in these directions. Solid lines describe upright flight, dashed lines describe inverted flight. Parts of loops connect these line segments (see e.g. the Humpry-Bump). Rolls in 1/4, 1/2, 3/4, etc increments up to 2 rolls can be added to the lines.

The looping portions in almost all figures have to have the same radius in all parts of a figure. For instance the quarter loops going into and coming out of a hammerhead have to have the same radius. There are some figures where this does not apply completely.

Rolls on vertical lines and on 45 degree lines have to be centered on this line to score well. Any deviation from the center results in a downgrading during a competition.

In this first post i will start explaining rolls, but come back and check later for all the aerobatic maneuvers, as i will be explaining all of them.

Rolls

Rolls can be added to most other figures to increase the difficulty factor of the figure. There are two basic types of rolls: slow rollss and snap rolls (flick rolls in european parlance).

Slow Rolls

1)

Slow Rolls 1
Slow Rolls 1

2)

Slow Rolls 2
Slow Rolls 2

Slow rolls have to be flown normally on a straight line (exception is the avalanche). The roll rate has to be constant and the longitudinal axis of the plane has to go straight. This requires constantly changing rudder and elevator control inputs throughout the roll. Hesitation or point rolls include stops at certain roll angles. The number on the base of the roll symbol describes the number of points the roll would have if it were a 360 degree roll. Allowed are 2 point, 4 point and 8 point rolls. The fraction on the arrow of the roll symbol describes what fraction of a full roll is to be executed. If no points are specified, rolling is done without hesitations. If no fraction is specified, a roll symbol that starts at the line specifies a half roll (see description of the Immelman). A roll symbol that crosses the line specifies a full roll (first figure). The second figure shows the symbol for 2 points of a 4 point roll (adding up to half a roll) from upright to inverted flight.

Snap Rolls

3)

Snap Rolls 1
Snap Rolls 1

4)

Snap Rolls 2
Snap Rolls 2

Snap or flick rolls also have to be flown normally on a straight line. A snap roll is similar to a horizontal spin. It is an auto rotation with one wing stalled. Figure 3 shows the symbol for a regular snap roll, figure 4 for an outside snap. In the regular snap, the plane has to be stalled by applying positive g forces. In an outside snap, the plane is stalled by applying negative g. In both cases rudder is then used to start auto rotation just like in a spin.