15-Meter Class The 15-Meter Class restricts wingspans to 15 meters or 49.2 feet. These sailplanes use flaps and interconnecting control surfaces, water ballast, retractable landing gear to increase performance.
18-Meter Class The 18-Meter Class is similar to the Open Class except with a wing span restriction to 18-meters or 59 feet.
Aileron A hinged portion of the wing that provides a banking or rolling force.
Airspeed The speed of the glider in relation to the air it is flying in.
Aspect Ratio The ratio between a gliders span and the cord of the wing. Long skinny wings are said to have a high Aspect Ratio.
Bank To tip or roll around the longitudinal axis of the glider. To bank to turn the glider.
Contest Director The head honcho at soaring competitions – the one who calls tasks and is responsible for ensuring that the contest is a safe, fair soaring competition.
Convection The up and down movement of the atmosphere normally related to thermal action.
Cumulus A cloud type whose origin is upward moving air. Typically these clouds look like fluffy cotton balls in the sky.
Drag The force opposing the forward motion of the glider (wind resistance when you stick your hand out the car window).
Elevator The horizontal movable surface of at the tail used to control pitch
FAA Federal Aviation Administration is the governing body of civil aviation in the U.S.
FAI Federation Aeronautique Internationale is the world governing body of aeronautical contests and records.
Feminine Class Feminine Class is restricted to female pilots.
Fin The fixed vertical tail surface, used to provide directional stability.
Finish Line An imaginary line that all competitors must fly through to finish the day’s competition.
Flap Hinged portion of the wing normally toward the fuselage that alters the lift and drag characteristics of the wing
Flight Computer Sophisticated computer that takes measurements of distance and performance to show the pilot the distance and speed they can glide to reach a point.
Flight Recording An electronic file that is a recording of the altitude and position of competitors while in flight. Normally generated by a secure recording GPS. Also called a Flight Trace.
Fuselage The area consisting of the cockpit and tail of the sailplane
G For gravity, the load on a glider is stated in terms of multiples of the force of gravity. Three “G” would equal three times the load than applied by gravity alone.
Gaggle A group of sailplanes circling tightly and sharing a thermal to climb in.
Glide Ratio The ratio of forward to downward motion. Forty five feet forward to one foot down to is called a glider ratio of 45:1
IGC The International Gliding Commission (IGC) of the Federation Aeronautique Internationale (FAI) is the Air Sports Commission which is responsible for all air sports activities involving gliders and motor gliders with the exception of glider aerobatics.
Junior Class Junior class restricted to pilots under the age of 26
Knot A unit of speed 15% faster than miles per hour
Land Out Landing someplace other than the contest airport sometimes in a farmers field.
Lenticular Cloud The characteristic cloud of lee waves normally found downwind of mountains
Max L/D The maximum performance of a sailplane normally expressed as Lift over Drag.
Open Class With Open Class sailplanes anything goes so wingspans can be up to 90 feet in length allowing these marvels to travel 60 feet forward to one foot down for a glide ratio of 60:1.
Pitot Tube An open-ended tube that faces toward the front of the glider that measures the impact air pressure for airspeed.
Red Line A warning mark on the airspeed indicator that corresponds to the maximum airspeed for the glider.
Rudder The hinged vertical control surface used to induce or overcome yawing
Sailplane A motor less craft that can climb using atmospheric forces alone. Referred to interchangeably as a glider.
Shot Down Unable to say aloft. Implies the weather rather than the pilot was a fault.
Sink Descending air currents
Soar To fly without power from and engine without loss of altitude.
Span The maximum distance between wingtips.
Spoiler Devices that disturb the airflow across the wings and create drag. Normally used for landing.
Standard Class The Standard Class are similar to the 15-Meter sailplanes except without interconnecting control surfaces or flaps.
Start An imaginary cylinder or “beer can” from which competitors must exit to begin the race on any contest day. Also called the Start Cylinder
Task The day’s competition course, normally including several turnpoints, around which competitors must fly on any given contest day. There is a different task chosen by the Contest Director each day and is weather dependent.
Thermaling Turning in tight circles to keep the sailplane inside the column of raising air.
Thermals Raising columns of warm air that allow sailplanes to gain altitude
Turnpoint A point that is designated by contest organizers that contestants must navigate to complete a task.
Variometer Sensitive rate of climb indicator that allows competitors to climb efficiently in thermals.
Water Ballast Water put in the wings of the sailplanes to improve high speed performance.
World Class The World Class is the one design class in which all gliders are restricted to a single design.
Yaw String A few inches of yarn on the front of the canopy indicating slip of skid.
(Source: USA Soaring Team)