The first time I saw a knife-edge circle was at the Tournament of Champions in Las Vegas, NV. Seeing an airplane rolled 90 degrees to knife-edge flight and having the pilot push on the elevator stick to initiate the circle while maintaining altitude with rudder was a sight to behold, and it still is!
To begin, the airplane should be flown in upright level flight, parallel to the runway, travelling into the wind at a moderate speed. For this example, the maneuver will be flown from left to right. At about 50 feet altitude and just before the airplane reaches you, roll the aircraft 90 degrees into knife-edge flight and apply top rudder to maintain altitude. Roll to the right to see the top of the airplane and apply left “top” rudder. As soon as the airplane is directly in front of you, begin to lightly push elevator to initiate the circle. The radius in the first 90 degrees dictates the size of the circle. As soon as the airplane is about 45% complete with the circle, begin the 1-1/2 positive snap rolls so that the snap rotation will be centered on the circle at the mid-way point of the circle. The direction of the snap roll should be the same direction as the top rudder. With top (left) rudder, the snap roll should be to the left. Once the snap is completed, immediately switch to top “right” rudder and begin pulling on the elevator to complete the second half of this knife-edge circle. Apply elevator and rudder input as needed to keep the same circle size and to maintain altitude. Once the maneuver is complete and the airplane is about 50 feet past you, perform a 90-degree roll to…
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