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Polar circle: flying at the top of the window

This lesson is part of the Cramayailes indoor 4-line school, restored by QuadKites.org. The text is Thierry Bressure’s, in the first person, translated from French. The video commentary is in French.

Prerequisite: 360.

The figure

Section titled "The figure"

Flying beyond the third level.

Watch the figure: polar circle

The lesson

Section titled "The lesson"

This is about flying beyond the third level, that is, higher than three revo heights.

At the top of the window, the relative wind is very weak and you cannot continuously generate vertical wind. The revo must be put into a glide, also called glide or float. At the very top of the window, the kite must fly in a glide.

Polar circle lesson by Cramayailes

Key takeaways from this video — Polar circle lesson

  • At the top of the window, the relative wind stays horizontal but becomes almost parallel to the kite's plane: a positive incidence is needed for it to generate lift.
  • You get this incidence with a little pressure on the brakes, so that the trailing edge is slightly lower than the leading edge.
  • To turn, accompany the kite by throwing the outer wing. Keeping the incidence, or giving a little more speed during the turn, avoids losing too much altitude; without tension on the lines, the kite falls.

Transcript — Polar circle lesson

  1. Flying at the top of the window

    0:00

    In this lesson, we are going to learn to fly at the top of the window. Not at the second level, which corresponds to two revo heights, nor even at the third level: I am really going to talk about the top of the window.

  2. Flight dynamics change

    0:43

    At the top of the window, the flight dynamics are greatly changed. Indeed, the relative wind, which is still horizontal, is no longer perpendicular to the kite’s wing, but almost parallel to the plane formed by the kite.

  3. Getting a positive incidence

    1:05

    As a result, to keep the kite flying, you must get a positive incidence, so that the horizontal wind can generate lift.

  4. Changing direction by throwing the outer wing

    1:21

    Changes of direction are also made differently. You can no longer brake the inner wing in the turn. You have to accompany the kite in the turn by throwing the outer wing.

  5. Incidence with a little brake

    1:55

    The positive angle of incidence I was talking about is obtained by lightly putting a little pressure on the brakes, so that the trailing edge is slightly lower than the leading edge. The kite thus forms an angle with the relative wind, which is enough to generate lift.

  6. The kite falls without tension on the lines

    2:32

    In turns at the top of the window, you will notice that the kite tends to fall as soon as you no longer apply enough pressure and tension on the lines.

  7. Keeping incidence during turns

    2:51

    To avoid losing too much altitude in turns, you really have to keep the angle of incidence throughout the turn maneuver.

    You can also give the kite a little more speed during the turn, to increase, to maximize this lift.

Video page: transcript, series and other uses

Movement

Section titled "Movement"

In a glide, the pilot can still move back in a circle.

Control

Section titled "Control"

The goal is to keep the kite flying at the top of the window, without further precision on its movement.

The circular movement is obtained by putting the kite flat. To do this, increase compensation to the maximum by moving away the hand that controls the outer wing (formerly called the lower wing) until the wing is fully flat. Once in this position, while moving back in a circle, you must maintain a positive wing incidence. Apply a little brake to tilt the trailing edge downward and so create a positive incidence.

Mastery of this movement is reached when the kite climbs almost to the zenith.

A variant is to fly a figure eight through the zenith. From the circular movement, you must throw the outer wing, because we have no vertical wind. At the top of the window, without vertical wind, you throw the outer wing to change direction. You may be tempted to put more brake on the inner wing, but doing so reduces the inner wing’s lift.

Careful: at the top of the window, the flight dynamics change, because the wind is horizontal and parallel to the kite, whereas at the bottom of the window it is horizontal and perpendicular to the kite!

What comes next

Section titled "What comes next"

The next lesson is the slide, leading edge down.

Last updated: — restored Thierry Bressure's polar circle lesson, with the figure reference