M1C2 To Fly the Lifting Power of Rising Air

altitude

elevation above sea level and ground level

aspect ratio

the ratio between the span of the wing and the chord length

convection

fluid motion between regions of unequal heating

density

mass in a given value

glide ratio

a mathematical relationship between the distance an aircraft will glide forward to the altitude loss.

lapse rate

the average rate at which temperature decreases with an increase in altitude. the average lapse rate is 3.5 degrees F per 1000 feet increase in altitude

lift-to-drag ratio

this ratio is used to measure the gliding efficiency of an aircraft.

soaring

the art of staying aloft by exploiting the energy of the atmosphere

span

the distance from wingtip to wingtip

spoilers

devices located on the wings that disrupt the airflow over the wing. This disruption causes a loss in lift. They also can serve as air, or dive, brakes

stability

the atmosphere's resistance to vertical motion

thermal

a column of air that moves upward

tow plane

usually a single-engined airplane that will pull a glider from the ground to an altitude where it can be released

wave

as air moves across mountain ranges, it sometimes starts a waving action with strong up and down motions. Sailplane pilots can use the motion of this wave to gain altitude