Mountain flying involves various skills that should be developed under the supervision of an experienced mountain flying instructor. Pilots who must fly over the mountains to reach a lowland destination can do so with a reasonable assurance of safety if they maintain an altitude at least 2000 feet higher that the highest elevation along the route of flight. This is the same altitude buffer required for IFR flights across mountainous areas. Whenever wind velocities exceed 20 knots, strong downdrafts and turbulence can be encountered on the lee side of mountain ridges. They should be crossed at or above 2000 feet AGL and at a 45-degree angle so that if downdrafts are encountered you can easily turn back toward lower terrain. In the event that an escape toward lower terrain is not possible and the aircraft is rapidly being pulled toward the ground, the best technique is to dive. Attempting to climb, even at the best angle of climb speed, will only keep the aircraft in the downdraft for a longer period of time, resulting in an even greater loss of altitude. Lowering the nose and increasing to cruising speed will result in an earlier escape. There will usually be a cushion of air closer to the ground which can be used to help slow the descent if the aircraft has enough airspeed.