The Physics While in Air
Photo credit: snoriderswest.com
Throttle and Brake Control
The key to midair handling is being aware of the throttle. While it may not look like it, the rider pictured to the left is in complete control, and knows exactly where his bike will land. This is due to physics. When in the air, giving the bike more throttle will result in the track rotating. This in turn, causes the sled to rotate back due to the angular momentum acting on the sled. The force of the track spinning counterclockwise will react against the mass of the sled, causing it to rotate clockwise around its axis of rotation, which in this case, is the bike's center of mass. Similarly, when the rider applies pressure on his brakes and the track comes to a complete stop, all of the counterclockwise angular momentum is transferred into the mass of the bike, causing it to rotate counterclockwise around its center of mass. It is in this way that a rider in midair can still be in complete control.
The key to midair handling is being aware of the throttle. While it may not look like it, the rider pictured to the left is in complete control, and knows exactly where his bike will land. This is due to physics. When in the air, giving the bike more throttle will result in the track rotating. This in turn, causes the sled to rotate back due to the angular momentum acting on the sled. The force of the track spinning counterclockwise will react against the mass of the sled, causing it to rotate clockwise around its axis of rotation, which in this case, is the bike's center of mass. Similarly, when the rider applies pressure on his brakes and the track comes to a complete stop, all of the counterclockwise angular momentum is transferred into the mass of the bike, causing it to rotate counterclockwise around its center of mass. It is in this way that a rider in midair can still be in complete control.
Photo credit: xgames.com
Launch Angle and Weight Displacement
Another very important aspect of jumping or cliff dropping on a snow-bike, is the angle at which the bike loses contact with the launch surface. As seen in the photo on the right, the rider is simply dropping from one level to another. He chose a spot with a relatively shallow drop angle because of the landing surface. His launch angle is about equal to the angle of the surface on which he will land. This allows for a very smooth transition. If the rider had chosen to launch from a steep, elevated angle, it would have sent him sailing much farther, and at a greater height. This would cause the rider to overshoot the landing, as well as come down much harder due to gravity acting over the additional distance. It is also very important to be aware of where your body is positioned. In the photo, you can see the rider is leaning slightly forward. This puts his center of mass in roughly the same position as the sled's center of mass, keeping the overall rotation to a minimum.
Another very important aspect of jumping or cliff dropping on a snow-bike, is the angle at which the bike loses contact with the launch surface. As seen in the photo on the right, the rider is simply dropping from one level to another. He chose a spot with a relatively shallow drop angle because of the landing surface. His launch angle is about equal to the angle of the surface on which he will land. This allows for a very smooth transition. If the rider had chosen to launch from a steep, elevated angle, it would have sent him sailing much farther, and at a greater height. This would cause the rider to overshoot the landing, as well as come down much harder due to gravity acting over the additional distance. It is also very important to be aware of where your body is positioned. In the photo, you can see the rider is leaning slightly forward. This puts his center of mass in roughly the same position as the sled's center of mass, keeping the overall rotation to a minimum.