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Do not use for real flight

Text and some pictures are available under the Creative Commons AttributionShareAlike License : CC BYSA

Gliding Soaring ......................................Thermal .....................................................Ridge lift ....................................................Wave lift ....................................................

Lauch method .........................................Self launch ................................................Aerotowing ................................................Winch lauching .........................................

Speed to fly Mc Cready ..........................FLARM .....................................................

Landing out ...............................................

What to do with your glider? .................Fly over beautiful landscapes! ..................Multiplayer session ...................................Fly online! .................................................

Plugin Thermals by Alex Ferrer ..............

Acknowledgment ......................................

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Summary

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Gliding

Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturallyoccurring currents of rising air in the atmosphere to remain airborne. The word soaring is also used for the sport.

Soaring

Glider pilots can stay airborne for hours by flying through air that is ascending as fast or faster than the glider itself is descending, thus gainingpotential energy. The most commonly used sources of rising air are :

> thermals (updrafts of warm air)> ridge lift (found where the wind blows against the face of a hill and is forced to rise)> wave lift (standing waves in the atmosphere, analogous to the ripples on the surface of a stream)

Ridge lift rarely allows pilots to climb much higher than about 600 metres (2,000 ft) above the terrain; thermals, depending on the climate andterrain, can allow climbs in excess of 3,000 metres (9,800 ft) in flat country and much higher above mountains; wave lift has allowed a glider toreach an altitude of 15,447 metres (50,679 ft).In a few countries such as the UK, gliders may continue to climb into the clouds in uncontrolledairspace, but in many European countries the pilot must stop climbing before reaching the cloud base.

Text is available under the Creative Commons AttributionShareAlike License (http://creativecommons.org/licenses/bysa/3.0/deed.fr)

Source italic text : Gliding / Wikipédia EN (http://en.wikipedia.org/wiki/Gliding).

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Thermals

Good gliding weather: Competitors studying cumulus humilis,which suggest active thermals and light winds.

Thermals are streams of rising air that are formed on theground through the warming of the surface by sunlight. If theair contains enough moisture, the water will condense from therising air and form cumulus clouds. When the air has littlemoisture or when an inversion stops the warm air from risinghigh enough for the moisture to condense, thermals do notcreate cumulus clouds. Without clouds or dust devils to markthe thermals, thermals are not always associated with anyfeature on the ground.

In XPlane :

Thermal coverage and thermal climbrate are configurable in the Weather menu (at thetop right page).Thermals are generated randomly.

For added realism, set some clouds.

See page 17 for more information about the Plugin Thermals by Alex Ferrer.



Thermals picture : https://www.soaringnv.com

The pilot must then use both skill and luck to find them using a sensitive vertical speed indicator called a variometer that quickly indicatesclimbs and descents. Occasionally reliable thermals can be found in the exhaust gases from power stations or from fires.

Once a thermal is encountered, the pilot can fly in tight circles to keep the glider within the thermal, so gaining altitude before flying towards thedestination or to the next thermal. This is known as "thermalling".

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Ridge lift

A ridge soaring pilot uses upward air movements caused whenthe wind blows on to the sides of hills. It can also be augmentedby thermals when the slopes also face the sun.In places where a steady wind blows, a ridge may allow virtuallyunlimited time aloft, although records for duration are no longerrecognized because of the danger of exhaustion.

To exploit this type of air movements, performs pilot roundtripalong the slope. Always keeping the nose of the glider in thewind, it applies a drift that prevents it from crossing the top of themountain. This shift is even more important and the speedincreases as the wind is strong.

In XPlane :Choose an airfield near a mountain.Set the wind direction in the weather menu : perpendicular to the mountain.

Tip: choose a scene near a mountain airfield.Example : Saint Martin De Londres, France > http://xpfr.org/?body=scene_accueil&seek=lfnl&x=0&y=0



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Wave lift

The powerfully rising and sinking air in mountain waves wasdiscovered by glider pilot, Wolf Hirth, in 1933.Gliders can sometimes climb in these waves to great altitudes,although pilots must use supplementary oxygen to avoidhypoxia.

This lift is often marked by long, stationary lenticular (lensshaped) clouds lying perpendicular to the wind.

Mountain wave was used to set the current altitude record of15,453 metres (50,699 ft) on 29 August 2006 over El Calafate,Argentina. The pilots, Steve Fossett and Einar Enevoldson, worepressure suits. The current world distance record of 3,008kilometres (1,869 mi) by Klaus Ohlmann (set on 21 January2003) was also flown using mountain waves in South America.

XPlane does not reproduce the wave lift.



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Launch methods

Most gliders do not have engines or at least engines that would allow a takeoff under their own power. Various methods aretherefore used to get airborne.Each method requires specific training, therefore glider pilots must be in current practice for the type of launch being used. Licensingrules in some countries, such as the USA, differentiate between aerotows and ground launch methods, due to the widely differenttechniques



Picture : www.whiteplanes.com

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Self launch

Selflaunching retractable propeller motor gliders havesufficient thrust and initial climb rate to take off withoutassistance, or they may be launched as with aconventional glider.The engines also have a starter motor and a largebattery to allow the engine to be started on the ground,and an alternator to recharge the battery.A twoblade propeller is typically coupled to the enginevia a belt reduction drive. In current production gliders,propeller alignment is fully automatic.

In XPlane :

The Antares 20E is a self launch glider. The electric propulsion system features a SingleLever Control for simple operation.See Flight Manual for information about using the engine.

Remember, the electric motor has an autonomy of 13 minutes ! It can climb 3,000 meters on one battery charge.


Source italic text : Motor_glider / Wikipédia EN (http://en.wikipedia.org/wiki/Motor_glider#Electric).

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Aerotowing

In an aerotow a powered plane is attached to the glider with a tow rope.Singleengined light aircraft or motor gliders are used. The towplane takesthe glider to the height and location requested by the pilot where the gliderpilot releases the towrope.A weak link is often fitted to the rope to ensure that any sudden loads donot damage the airframe of the towplane or the glider. Under extremeloads the weak link will fail before any part of the glider or plane fails.There is a remote chance that the weak link might break at low altitude,and so pilots plan for this eventuality before launching.

In XPlane :

Menu Aircraft > Aircraft & Situations.Choose GliderTow option.

Check flaps, trim and Airbrakes position.Click white handle to release Brakes (or press 'B' key).Click yellow handle winch to drop the cable when you are ready to glide on yourown (or press 'Space Bar').



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Winch launching

Gliders are often launched using a stationary groundbased winch mounted on aheavy vehicle. This method is widely used at many European clubs, often in additionto an aerotow service. The engine is usually a large diesel, gasoline or LPG engine,though hydraulic fluid engines and electrical motors are also used. The winch pullsin a 1,000 to 1,600metre (3,000 to 5,500 ft) cable, made of hightensile steel wire ora synthetic fiber, attached to the glider. The cable is released at a height of about400 to 700 metres (1,300 to 2,200 ft) after a short, steep ride.



Winch Picture By dontworry GFDL (http://www.gnu.org/copyleft/fdl.html), CCBYSA3.0 via Wikimedia Commons

In XPlane :

Menu Aircraft > Aircraft & Situations.Choose GliderWinch option.

Click white handle to release Brakes (or press 'B' key).Click yellow handle winch to drop the cable when you're at the top of the loop(or press 'Space Bar').

Note : this method is not recommended with the Antares.

11Text is available under the Creative Commons AttributionShareAlike License (http://creativecommons.org/licenses/bysa/3.0/deed.fr)

Source italic text : Speed to fly / Wikipedia EN (http://en.wikipedia.org/wiki/Speed_to_fly).

Speed to fly Mc Cready

Speed to fly is a principle used by soaring pilots when flying betweensources of lift, usually thermals, ridge lift and wave. The aim is tomaximize the average crosscountry speed by optimizing the airspeed inboth rising and sinking air. The optimal airspeed is independent of thewind speed, because the fastest average speed achievable through theairmass corresponds to the fastest achievable average groundspeed.

The idea is usually attributed to Paul MacCready, although an earlyversion of the theory was first described by Wolfgang Späte in 1938.However Späte may not have considered sinking air between thermals,and there is no mention of this until 1947 when Ernest Dewing andGeorge Pirie independently included this aspect.Paul MacCready, however, certainly invented the "ring", which allowed aneasy indication of the optimal speed to fly.

In XPlane, with the Antares 20E :

See flight manual to use the MacCready function.

12Text is available under the Creative Commons AttributionShareAlike License (http://creativecommons.org/licenses/bysa/3.0/deed.fr)

Source italic text : FLARM / Wikipédia EN (http://en.wikipedia.org/wiki/FLARM).

FLARM

FLARM is an electronic device to selectively alert pilots to potentialcollisions between aircraft. It is not formally an implementation of ADSB,as it is optimised for the specific needs of small aircraft such as gliders, notfor longrange communication or ATC interaction.

In XPlane, with the Antares 20E :

Click FLRM button (LX main screen) to display the FLARM radar.See the flight manual page.

Landing out

If lift is not found during a crosscountry flight, for example because ofdeteriorating weather, the pilot must choose a location to "land out".

Although inconvenient and often mistaken for "emergency landings",landing out (or "outlanding") is a routine event in crosscountry gliding.The pilot has to choose a location where the glider can be landed safely,without damaging the plane and the pilot.

The glider and the pilot can then be retrieved by road from the outlandinglocation using a purposebuilt trailer. In some instances, a towplane can besummoned to relaunch the aircraft.

In XPlane :

Find a flat and open terrain.Check the wind, heading and speed.Unroll the landing checklist.

Alternatively, you can deploy the engine to regain altitude. Check the battery charge!



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To enjoy your flight with the glider, install sceneries. Rediscover the world with the Antares !

What to do with your glider?

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Fly your glider over beautiful landscape!

Explore sceneries!Great Visibility with the Antares. Normandy American Cemetery

14710 CollevillesurMer, France

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Fly with your friends inmultiplayer session!

Read XPlane manual for instructions.

Fly online!

Network IVAO or VATSIM.Enjoy your flight with real pilots and ATC. Share the sky.

On IVAO you can fly a Glider Tour !Example :http://www.ivao.fr/dep/TDF/presentationtp1.htmlhttp://www.ivaochile.org/portal/index.php/eventos/tours/tour2014glider

Plugin Thermals by Alex Ferrer

According Alex :

« XPlane plugin to generate more realistic thermals (Requirespython plugin).The current Xplane (Ver 10.30+) thermal model is quitesimplistic. This is an attempt to create a plugin that simulatesthermal of better realism.Basic concept: Create a fixed or random list of thermals withlat,lon,thermal diameter, thermal strength While flying, detectcollision between the aircraft and the thermals, apply the lift tothe aircraft. »

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Read this page for more information and download :

http://forums.xplane.org/index.php?app=downloads&showfile=24381

https://github.com/alexferrer/xplane_thermals

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How to install PythonInterface and the thermal plugin (XPlane 10)

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For more information about Python Interface, check the Sandy Barbour page :

http://www.xpluginsdk.org/python_interface_downloads.htm

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Text and some pictures are available under the Creative Commons AttributionShareAlike License : CC BYSA

Acknowledgment

JeanFrançois for advice, translate EN.Bernard for advice.Alex Ferrer for the Thermal plugin.Sandy Barbour for Python Interface.

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