Soaring is a manner of flying wherewith glider pilots once launched, using upward moving air currents called “lift”, maintain and even increase altitude during their flights using no outside energy other than this atmospheric “lift” for power.
Soaring can be done for fun, as a hobby, and also competitively in organized soaring contests. Soaring objectives beyond the joy and feeling of freedom it procures, include : flying the longest possible distance with either a fixed destination or circuit, or a free circuit for the longest distance possible, or again flying for the longest distance within a specified time limit.
THE HISTORY OF SOARING
The history of soaring starts with the history of heavier-than-air flight. The first manned winged flight in history was accomplished by Guillaume Resnier at Angouleme in France in the early 1800s, followed by the soaring pioneer Otto Lilienthal making gliding flights between 1891 and 1896 near Berlin in Germany. The Wright brothers in the early 1900s are recognized for having made the first gliding then sustained flight with a controllable machine incorporating a launching principle.
Unpowered sustained flight was developed essentially in Germany in the period between the first and second world wars when Germany was forbidden to develop powered aircraft. German gliding aviators discovered and developed the various methods of using air currents (especially upward moving air currents) to fly farther and for longer flight-times. This culture has spread around the world, however German know-how and design expertise for gliders remains the worldwide reference.
Soaring is defined as flying in air masses which have higher upward movement speed than the sink rate of the glider, thus increasing the glider’s potential energy. To accomplish this accumulation of potential energy, gliders will adopt a circular trajectory with the objective of staying within the upward-moving air masses (spiraling). The objective is to reach the maximum altitude for each ascendency. Altitude thus becomes the glider’s “fuel”. One could say that the glider fills its tank at each ascendency. Neophyte pilots will do this every 7 to 8 km or so up to 25 km, and much more for experienced pilots.
The different types of upward moving air masses used by glider pilots generating lift :
Thermal lift which is the consequence of the uneven heating of the ground surface by the sun, heating the air in turn, and producing “columns” of rising “hotter” air (thermal lift) which a glider can use to gain altitude by climbing to the base of the cloud (cumulus) produced by this rising hot air. This phenomenon occurs from spring to early autumn;
Dynamic lift which is produced by winds encountering mountain ridges and being forced upwards at a rate depending on wind speed and ridge shape. When the ridge is exposed to the sun, heating occurs, and thermal lift will also be produced. Gliders may exploit this combined lift and climb to up to 700m above the ridge line.
Wave lift : when wind and mountain conditions are perfectly aligned, this situation can result in soaring altitude gains up to and beyond 10 000m thanks to lee waves. Lenticular-shaped clouds stacked like plates or floating individually high above the mountains are a sign of lee wave activity. Soaring in the wave is a bit like surfing.
Generally speaking, glider flights will last from a few hours, up to 10 hours, with distances covered of up to 1000km.
Launching a glider is accomplished either by means of a tow plane called a “tug” which pulls the glider up in the air during the takeoff phase, and then tows the glider to an appropriate release point where there is adequate lift, or, by swiftly winching the glider up to a height of 300 to 500m above the airfield with a powerful winch in the manner of a person running to launch a kite.
Self-launching motorized gliders take off and climb to soaring height using a fixed or retractable motor.
At the time of this writing (February 2016), Klaus Ohlmann holds the world record for distance with a flight of 3009km. Also Steve Fossett still holds the world soaring altitude record of 15 460m.
A soaring flight conducted such as to maintain gliding distance/altitude from the base airfield permitting rapid return to base and landing is called a “local” flight. This type of soaring is fun and permits flight within a circle of 10km around the base.
Cross-country soaring is on the other hand flying with a fixed or non-fixed destination, beyond return gliding distance/altitude from the base. To ensure safety, the cross-country pilot must ensure he/she is at all times within safe gliding distance to a known or opportunistic “out-landable” field.
LANDING WITH THE COWS
In the event that soaring conditions degrade during a flight, or if for any reason a pilot cannot return to base or land on an airfield, he must make the decision to land in a field. This is called an “outlanding” (in French “se vacher”). After landing, the glider will be dismantled on site, then put into a trailer and towed back to base for reassembly.
It is true to say that many pilots fly for personal enjoyment only, however competition soaring is the preference of many other pilots.
Soaring contests require that pilots and co-pilots use all of their piloting skill and experience to best exploit the aerological conditions encountered during a contest. The general idea will often be to complete a fixed circuit comprised of a certain number of turning points which the glider must over-fly, in the shortest possible time. A common variation of this is a contest in which the objective is to cover the greatest distance in a given time, and return to the launching point.
Aerobatic flight may also be done in gliders. In this discipline pure piloting skill and technique is at its very zenith. In aerobatic competition flight, the glider will effectuate various maneuvers such as loops, rolls, inverted flight, hammerhead stalls… Competitors are judged and classed according to precision of the maneuvers.
The gliding pilot license is obtained following a written exam (concerning gliding theory, aerodynamics, navigation, meteorology, human factors…) and a flight test with an instructor in a dual control glider to evaluate piloting competency and capacity to prospect for and exploit lift.
Generally, the training progression will include approximately 20 hours of dual control flight with an instructor before the student pilot’s first solo flight. This will be followed by 10 more solo flights (1 flight lasting longer than one hour in length).
Earning the Federation Aeronautique Internationale (FAI), Silver Badge requires a glider pilot to accomplish a 5-hour flight with an altitude gain of 1000m and covering a distance of 50km. For the Gold Badge, the pilot must accomplish a 300km cross-country flight with a 3000m altitude gain. The Diamond Badge requires respectively 500km and 5000m.
French regulations concerning authorization to fly with a passenger require a flight test plus an evaluation of the candidate’s pilot-in-command experience.
Authorization for cross-country flight permitting long-distance flights is given following specific training including dual control and solo landings off base airfield, and accomplishment of a 50km flight.
Soaring is most often practiced within club organizations in France.
The Aeroclub International Sisteron (ACIS) is one of the highest ranking FFVV affiliated gliding clubs in France.
THE FRENCH SOARING FEDERATION
FFVV - Fédération Française de Vol à Voile