A paraglider's glide ratio is the distance it covers for the height it loses, in still air: glide ratio = distance ÷ height lost. A worked example in Gréolières: from the highest take-off, at 1,800 m, to the landing field, at around 800 m, there are about 1,000 m of height. With a glide ratio of 8, chosen for the example, those 1,000 m give about 8 km of gliding flight.
Gliding flightThe glide ratio of a paraglider is the ratio between the horizontal distance it covers and the vertical distance it loses, in still air. A glide ratio of 8 means 8 metres forward for every metre of descent.
Glide ratio = distance covered ÷ height lost
or, which comes to the same thing, glide ratio = horizontal speed ÷ vertical speed (the sink rate)
Example calculation: a wing flying at 10 m/s (36 km/h) and sinking at 1.25 m/s has a glide ratio of 10 ÷ 1.25 = 8. Its glide angle is then about 7 degrees: a paraglider glides, it does not fall.
In Gréolières, our take-offs are at 1,100, 1,500 and 1,800 m, and the landing field at around 800 m. From the highest one, there are about 1,000 m of height: with the same glide ratio of 8, that makes about 8 km of gliding flight in still air, and just over 13 minutes in the air at a sink rate of 1.25 m/s. From the 1,100 m take-off, the 300 m of height give about 2.4 km.
These are illustrative calculations: they do not give the distance to the landing field, and the real glide ratio depends on the wing, the wind and the air of the day. In rising air, the flight lasts much longer.
The glide ratio is part of flight mechanics, one of the topics of the theory exam: our paragliding certificate quiz lets you practise.
The air glide ratio is the wing's glide within the air mass; the ground glide ratio is the one you measure relative to the ground. In still air, the two are equal. With wind, the ground glide ratio changes, and it is the one that tells you whether you will reach where you want to go.
Here is the calculation with the glide ratio 8 wing seen above (36 km/h and a sink rate of 1.25 m/s), for 1,000 m of height:
| Situation | Speed over the ground | Ground glide ratio | Distance for 1,000 m |
|---|---|---|---|
| Still air | 36 km/h | 8 | 8 km |
| 18 km/h headwind | 18 km/h | 4 | 4 km |
| 18 km/h tailwind | 54 km/h | 12 | 12 km |
In this example, an 18 km/h headwind halves the distance; the same wind from behind increases it by half. The wing's own glide ratio has not changed.
The air mass matters as much as the wind. In rising air, the wing sinks more slowly relative to the ground, and can even climb: that is the whole principle of thermal paragliding. In sinking air, it loses height faster; you then speed up to cross the area.
The speed polar is the curve that links, for a given wing, its horizontal speed and its sink rate. It shows that the glide ratio changes with speed: each wing has a best glide, reached at a precise speed.
This is the speed at which the wing sinks the slowest, usually with a little brake. It is used to hold altitude and to climb in rising air, not to go far.
This is the speed that gives the greatest distance in still air, most often close to hands-up speed, with no brake. On the polar, it is the point touched by a straight line drawn from the origin.
With the speed bar, the wing flies faster but sinks more: its air glide ratio drops. Into the wind, though, it can gain ground glide ratio, because it makes better headway against the wind.
It gives the wing's speeds, hands up and on speed bar, and its settings: for your wing, it is the reference, together with your instructor's advice.
In flight, you choose the speed that suits the moment: slow to climb, hands up to go far in still air, faster into the wind or in sinking air. These choices are part of paraglider piloting.
There is no single glide ratio for “a paraglider”: it depends on the wing's design and on the way it is flown. When a manufacturer gives a glide ratio, it is a still-air value; in flight, the wind and the air of the day count for more.
An EN-A certified school wing, like the Aerotech A1 used on our courses, or a wing for pilots just out of school favours tolerance and simplicity, with a more modest average glide ratio. The higher the category, the more the wing seeks performance, and the more piloting it demands.
The higher a wing's aspect ratio, in other words the wider its span relative to its depth, the more glide potential it has; it also demands more piloting.
A more heavily loaded wing flies faster. In theory, its best glide changes little: it is reached at a higher speed, which helps into the wind.
A porous wing or one with an out-of-trim line set loses performance: workshop servicing checks these points. The harness matters too: a pod harness offers less drag.
An example of a higher-performance wing: the Ozone Delta 5, which we have tested, is an EN-C certified 2-liner, according to Ozone's specifications. Fewer lines mean less drag: that is one of the levers of glide performance.
We do not give a glide ratio per category here: each wing has its own. For a specific wing, read its manufacturer's specifications; to compare two wings, a test flight tells you more than a number.
To know whether you will reach a point, your eyes are enough. A classic visual method, the fixed-point method: look ahead for the point on the ground that does not move in your field of view. If the air does not change, that is where your flight path will meet the ground.
At this ground glide ratio, you will not reach it: to make the landing field, you need a thermal, or a closer target.
You will pass over it: you have margin to reach it.
The wind and rising air move this point along the way: you keep an eye on it throughout the flight. Our paragliding aerology guide explains these air movements.
At Ailéments, we first learn to feel and to look: the wing, the air, the terrain. A GPS instrument, such as a GPS variometer, can display a ground glide ratio; a variometer is only recommended after a few years of flying, and it is never compulsory.
Pierrot, the school's founder, has been flying without a variometer for at least ten years: he prefers to sharpen his senses rather than listen to a beep.
A wing's specification sheet gives, size by size, the flat and projected area, the span, the aspect ratio, the number of cells, the wing's weight, the total flying weight range and the certification. Four of these numbers matter when choosing.
Total flying weight is you and everything that flies with you: wing, harness, reserve, helmet, clothing and instruments. It must fall within the certified range of the chosen size.
For our students, we count 15 kg of gear: a 70 kg student therefore flies at around 85 kg total flying weight. Here are the ranges of the Aerotech A1, the EN-A certified school wing used on our courses:
| Size | Wing range (total flying weight) | Recommended range for beginners |
|---|---|---|
| Size S | 55 to 90 kg | 55 to 70 kg |
| Size M | 70 to 110 kg | 70 to 90 kg |
| Size L | 90 to 125 kg | 90 to 105 kg |
The recommended range for beginners is the bottom of the wing's range: less loaded, the wing reacts more gently. Our student at 85 kg total flying weight falls within the range of size S, but right at the top; in size M, he is within the recommended range for beginners.
Wing loading is the total flying weight divided by the wing's flat area:
Wing loading = total flying weight ÷ flat area, in kilos per square metre (kg/m²)
An example with the numbers from Ozone's specifications for the Delta 5: size MS has a flat area of 22.8 m² and is flown from 75 to 95 kg total flying weight. At 85 kg, its wing loading is 85 ÷ 22.8 = 3.7 kg/m²; it ranges from 3.3 kg/m² at the bottom of the range to 4.2 kg/m² at the top.
The higher the wing loading, the faster the wing flies and the more lively its reactions. Where to sit within the range is decided with an instructor, according to your level and the sites you fly.
The European standard EN 926-2 classifies wings into four categories, after test flights that observe how the wing reacts to a disturbance and returns to normal flight. The category tells you the level of piloting the wing demands:
The EN 926-1 standard, for its part, covers the strength of the wing's structure.
A spec sheet also gives the flat area (the wing laid out on the ground) and the projected area, the aspect ratio and the number of cells: according to Ozone, the Delta 5 has 65 cells, with an aspect ratio of 6.07 flat and 4.57 projected.
A specification sheet is best read with an instructor: they know your level, your total flying weight and the sites you are going to fly. The right wing is the one you fly calmly, not the one with the highest glide ratio.
You and your gear: the total must fall within the size's range, towards the bottom for beginners.
EN-A for school and the first years, then one category up when your level allows it, with an instructor's advice. Our guide to your first paraglider wing explains this choice.
At Aerotech, in Gréolières, a test flight on a wing is free, subject to availability. Our paraglider buying advice explains how we support you.
The price of a paraglider includes the harness, the reserve parachute and the helmet.
Our paragliding courses prepare you for the FFVL Initial Pilot Certificate: the theory, flight mechanics included, is worked on both in the field and in the classroom. Our paragliding certificate page details the steps and the budget.
To feel a gliding flight before learning, take a tandem flight with an instructor: you can even take the controls.
Book a flightCalculation, best glide, hang glider, total flying weight, certification, instruments.
Divide the distance covered by the height lost, or the horizontal speed by the sink rate. Worked example: a wing flying at 10 m/s and sinking at 1.25 m/s has a glide ratio of 8, that is 8 km for 1,000 m of height in still air. With wind, you calculate the ground glide ratio using the speed over the ground.
There is no single number: the glide ratio depends on the wing's category, its aspect ratio, its loading and its condition. For a specific wing, see its manufacturer's specifications or ask an instructor. To picture the idea: with a glide ratio of 8, chosen for the example, 1,000 m of height give about 8 km of gliding flight in still air.
It is a wing's highest glide ratio, reached at a precise speed, most often close to hands-up speed. It can be read on the speed polar, the curve linking speed and sink rate. At this speed, the wing goes the furthest in still air; into the wind, you fly faster to keep a good ground glide ratio.
Glide ratio is measured in the same way for any aircraft that glides, from paragliders to sailplanes. The hang glider, a wing stretched over a rigid frame, generally glides better and faster than the paraglider, a flexible wing with no frame: its glide ratio is higher. The paraglider flies more slowly and packs into a rucksack. At Ailéments, we only fly paragliders; the FAQ on our paragliding page compares the two wings.
It is your weight plus that of all the gear that flies with you: wing, harness, reserve, helmet, clothing and instruments. It must fall within the certified range of the wing size; for our students, we count 15 kg of gear.
They are the categories of the EN 926-2 standard, awarded after test flights. EN-A refers to the most tolerant wings, for school and the first years; EN-B, a wide progression category; EN-C, performance wings for experienced pilots; EN-D, very demanding wings. The Aerotech A1 used on our courses is EN-A.
No. Your eyes are enough to judge your arrival: the point on the ground that stays fixed in your field of view is the one you will reach if the air does not change. At Ailéments, a variometer is only recommended after a few years of flying and is never compulsory: Pierrot has been flying without a variometer for at least ten years.
