Mid-air collisions:
In principle the glider pilot has a smaller probability of having a mid-air collison when flying than a collision when driving because flight occurs in 3 dimension whereas the car is constrained to move in 2 dimensions. However this this advantage is lost because pilots often fail to maintain a continuous scan for other aircraft while they are distracted reading maps, adjusting instruments, etc which can take a minute or more. In addition, aircraft typically converge at higher velocities and are difficult to spot because they approach from 3 dimensions. Since mid-air collisions are relatively rare the pilot can be seduced into complacency and into failing to continuously scan for traffic. The following are recent examples of recent glider collisions.
February 6, 2010:, Boulder CO: A Cirrus aircraft ran into a Pawnee towing a Schweizer 2-32 over Boulder. The 2 Cirrus occupants plus the Pawnee pilot were killed. Fortunately the Glider pilot released from the tow on seeing the collision so he and his two passengers landed safely.
28 November 2009, Cazy Creek, CA: An ASW27 collided with the Pawnee tow plane as they turned onto final and both pilots were killed. Like Dansville, the power traffic used a left-hand pattern while the glider traffic a right-hand pattern. Prior to the head-on collision they did not communicate nor see each other.
14 June 2009 Oxfordshire: A RAF Tutor training aircraft ran into a glider. The glider pilot parachuted to safety, the 2 power pilots were killed.
15 January 2009; New York: An Airbus 320 collided with a flock of geese and ditched in the Hudson. Sully the pilot was a glider pilot.
2006 Minden CA: A descending private jet collided with a thermalling ASG29. The glider pilot parachuted to safety while the jet made a safe emergency landing.
Keep your eyeballs busy scanning for other aircraft. Rely on the vario audio plus tactile senses to thermal. Note that even though the glider is smaller