How does paragliding work? Why does it flying?
If you’ve recently been drawn to the possibility of paragliding, it’s normal that you are wondering how does de paragliders work and why paragliders fly. By knowing the answer to these questions, you may feel safer when you practice this activity.
What is paragliding?
The paraglider is the name given to flexible and lightweight gliders. That is, paragliders are considered gliders because of the way they manage to stay in the air, as they do not use any engines.
The paragliders are made of ropes and fabric, without having a rigid structure more than the part where the pilot goes.
How does a paraglider fly?
Given the above information, many people believe that paragliders do not fly and that they only serve to get down, something similar to what happens with a parachute.
However, you should keep in mind that paragliders do fly the same way gliders do. This is because paragliders have the aerodynamic ability to plan. They fly because they have the same aerodynamics as airplanes, with a displacement in the air that manages to create the so-called “relative wind”, which is responsible for generating the forces that make it possible to sustain the flight.
That is, paragliders are driven by gravity and their wings has a shape designed to plan without motor. In addition, the wing is also responsible for taking full advantage of aerodynamic forces, as well as thermal ancestry and wind force for keeping in the air.
To all of the above you can add the fact that the paragliders are ultralight weighing less than the pilot, so it can take off and land standing very easily. Even without the need for large wind currents.
The paragliding does not use any mechanism beyond the pilot’s legs to be able to take off and land, this being one of the main reasons why it is very easy to use. It does not require an external force or impulse to be able to fly.
How does paragliding works?
We’ve already talked about the forces and factors to consider knowing how a paraglider fly. However, there are still some aspects to review so that you have no doubt about how a paraglider works.
As we have stated, one of the biggest advantages of paragliding is that they are very simple: they do not use an engine to fly and instead make the most of their aerodynamic capacity. They are driven by the strength of the weight along with the design of their wing, allowing you to plan without the need to have any impulse.
Wind force, thermal ancestry and aerodynamics are used to help the paraglider plan. The use of these three forces is what makes it possible for us to paraglide so easily.
Thermal ancestry is the phenomenon that allows the paragliding to gain height and can stay in the air. So, we can say that it is a fundamental force to be able to plan comfortably.
This also means that the duration of the paragliding flight is directly related to weather conditions, so this must be taken into account before embarking on the flight.
To have the best possible experience it is very important that the weather conditions are adequate. This means that it is not recommended to fly when it is snowing, raining or hating.
Depending on the weather, the flight can last between 10 minutes and many hours, although experts recommend that the flight session not last more than 30 minutes if you fly in tandem for the first time.
Another great advantage is the flexibility of gliders. Because they are made of materials and fabrics that do not have a large rigid structure, these are really flexible. This means that they can be stored very easily even inside a backpack, so you can be sure that transporting and storing a paragliding is a simple thing.
Now you know what paragliders are, why they fly and how they work, so you should be much clearer if it’s an activity you want to experience. There are many schools where you can start learning from the basics in the company of an expert teacher, so the classes are very safe and so you can gain ease with each session.
What is Paragliding?
What is paragliding? It’s one of the rawest and most pure forms of flight. It involves the use of a paraglider, where the pilot sits in a harness which is suspended by a large, curved fabric wing. There is no engine, pilots launch by running and obtaining lift. The curve in the wing enables a skilled pilot to glide over long distances and to climb to high altitudes. Steering is conducted by pulling handles which are located beside each shoulder.
Paragliding is one of the simplest forms of flight and easiest to get involved in. It’s a popular hobby for those who not only enjoy the skill and thrill of flight, but also enjoy the outdoors and the amazing overhead views obtainable.
However, like other forms of flight, paragliding takes time to learn and master. There are dangers involved and loss of control, sudden weather change, or mishandled equipment can result in death.
What is the History of Paragliding?
Paragliding has a relatively short history, involving many people across the United States and France. Early versions of paragliding were derived from the preexisting parachute, which was round in shape, and designed to descent safely.
The earliest known paragliding was performed by the US military in their parachute landing training. Repeatedly flying soldiers back into the air to jump out of a plane was time consuming. It was less costly, less time consuming and enabled more jumps to be performed in the day if soldiers made their own way into the air through paragliding.
The first recorded history dates back to 1952 where American Domina Jailbert successfully patented a gliding parachute with multi-cells and controls to enable lateral gliding. In 1963, Domina invented and patented the Parafoil. It’s ‘ram-air’ design contains many cells which collect air and once full, enable the pilot to take off. The shape had evolved from a round parachute to a rectangular, slightly curved wing.
Also in the 1960’s David Barish was working with NASA space capsules in the development of a sail wing as a recovery system to bring astronauts back to Earth. He created a rectangular shaped parachute. Barish took this idea to ski resorts throughout the United States, trying to get “slope soaring” to take off. At the time it was simply seen as a way to race down grassy ski slopes in the summer, skimming above the ground. There was no intention to leverage thermals or dynamic wind and glide high in the sky.
In 1961, French engineer Pierre Lemongine also made advancements to help enable the possibility of paragliding. He developed a parachute design which could be towed into the air and steered.
It wasn’t until 1978 when paragliding started to gain momentum. The defining moment was on June 25th, when two French skydivers Jean-Claud Betemps and Andre Bohn ran down the sleep mountain slope of Mont Pertuiset in France and launched into the air. Betemps and Bohn were training for the national skydiving championships in France and couldn’t afford to pay for fuel for a plane to take them up and down the mountains. At the time they were not aware of David Barish’s earlier work on the other side of the world, but asked scientists if their plans were possible, receiving a somewhat cautious “yes”.
Their paragliding was shown in the media, which encouraged others to try the sport and led to Betemps who was first to paraglide on the day, to become known as the inventor of paragliding.
From this moment on the popularity of paragliding steadily grew. In 1979 the first paragliding school was established, with Betemps as an instructor. The first paragliders become available for the public to buy in 1985. The wing fabric was stiffer than that of a parachute and the lines less elastic. This provided greater control and stability for the pilot.
What Components Make Up a Paraglider?
The main part of the paraglider is called the wing. This looks similar to a parachute, however instead of being round, it’s rectangular in shape and curved. These wings have two layers of fabric, usually ripstop polyester or nylon, which are connected by cells. The curved shape of the wing and it’s cells enable it to collect and hold the wind on takeoff and in flight. This is known as the ram-air airfoil design. There are different types of paraglider wings to choose from, depending on the type of turbulence which may be expected, and the speed that the pilot desires.
The pilot sits in a harness that is suspended below the wing. These can vary from a basic harness setup which is little more than a series of straps, to something with significant protection, like a chair. These more advanced harnesses will hold a reserve parachute under the seat which can be quickly deployed by pulling a handle. These harnesses also provide benefits such as protection from cold air in high alpine altitudes, storage and foam or airbag protectors in the event of a failed takeoff or rough landing.
Nowadays most paragliding pilots fly with a reserve. However this should only be used in when the pilot is completely sure they cannot regain control of the paraglider. Opening a reserve presents new risks such as not being able to control where you land, as well as candlesticking (where the main wing and parachute come into contact and twist into each other). In the possible event of candlesticking, many competitive pilots carry two reserves. As a paraglider it’s best to ensure that you have adequate training and can handle difficult conditions or avoid them completely, rather than fly through anything in the knowledge that you have a reserve.
Paraglider Tech (Variometer, GPS, Radio, Compass)
A variometer is important for measuring your vertical speed, as well as other variables such as relative altitude, actual altitude, air temperature and air speed. Most variometers can give you audio warning tones and record data from your flight which can be downloaded to your computer.
Some variometers also contain a GPS, otherwise pilots will use a separate GPS unit. GPS systems are very useful for paragliders as when your a mile above the ground, it’s harder to notice if changing weather conditions are causing you to slow down or drift backwards. Those who fly in high alpine conditions will carry a digital compass incase they fly through cloud, where GPS units are not effective.
Helmet for the Unexpected
Good paragliding helmets are made of kevlar for light weight and strength. Accidents can cause head trauma from any angle, therefore helmets contain full protection to the head. A large faceguard is particularly useful in the event that a launch does not go to plan.
Footwear Suitable for Landing
Believe it or not, the ankle is the most commonly injured part of the body in paragliding. For many people hiking boots will suffice, but regular advanced users will wear a specialist boot with high sides to protect the ankle from trauma. Paragliding boots are also designed not to have external lacing clips as these can snap on your lines.
Flying, controlling and Landing a Paraglider
Launching a Paraglider
There are three main forms of paraglider take off, the forward launch, reverse launch and a towed launch. The forward launch involved the pilots wing being spread out on the ground with the pilot running forward. This is done in an airstream, often on higher ground. Some pilots prefer this as they only have to run forward, and get the thrill of takeoff. However the disadvantage of this is that the wing is behind you, making it harder to check for correct inflation and no tangling of lines.
In strong winds, particularly at high altitudes, a pilot may choose a reverse launch. Little running from the pilot is required and the pilot can also watch the wing and lines as they leave the ground. However, skill is required to execute this launch successfully, requiring the pilot to hold the brakes, turn to the side and avoid tangling the lines.
A towed launch can involve the aid of a stationary object such as a winch, car or boat. This can make it easier to paraglide from flat ground with little wind.
Controlling the Paraglider
Pilots can increase speed by using the speed bar, which can be controlled using their feet. This is connected through the harness and decreases the wing’s angle of attack. Braking is controlled by two controls, one on each side of the pilot. These are used to adjust speed and a pilot can also use them to manipulate steering by shifting their body weight at the same time.
A skilled pilot can also use lines and risers to control the wing. This can be useful for speeding up the approach to a landing, slowing down if the brakes fail, or for retaining control in sudden changes of wind.
For the most part, the pilot can let the paraglider glide itself. A common mistake by beginners is to spend too much time overcorrecting and braking.
It’s important that a paraglider landing is well planned and performed gradually. Hitting the brakes hard early in the landing often results in a harder landing and injury. Pilots are taught to resist a poor landing and take their time to land in ideal conditions where possible. Landing with the wind can assist in a smooth landing, landing without wind can require the pilot to exercise some skill and ‘flare’ at the end of the landing. This involves speeding up as you get close to the ground to flare the wing and reduce the chance of a hard impact. Once your close to the ground, legs are down, wing is flared, and your final checks tell you that the ground is safe to land on, you’re then ready to hit the brakes.
If a more rapid landing is necessary, an experienced pilot may be able to perform a spiral dive, b-line stall or big ears landing, depending on the conditions and space available.
What are the Types of Paragliding?
The are different forms of competitive paragliding, to suit those with different interests and abilities. Most fall into three main categories: cross-country flying, aerobic paragliding competitions, and hike and fly paragliding competitions.
Soaring is performed by using wind which is guided up by a large object like a mountain, cliff, ridge or large sand-dune. A constant and suitable level of wind is required to do this. If there’s not enough wind, the paraglider won’t make a clean takeoff. If there is too much wind, the paraglider can be blown back over the slope.
Thermal flying leverages the thermals which rise through the air from objects such as rocks which have been warmed in the sun. When pilots find a thermal, they will use a varioaltimeter or fly in a circle, to find the strongest part of the core of the thermal where the air is rising faster.
Cross-country paragliding involves gliding from one thermal to the next. Paragliders will glide towards land features which could generate thermals or look for cumulus clouds to fly under, as these are usually found at the top of a warm air thermal.
What Does Paragliding Feel Like?
Most people who have tried it will tell you that paragliding feels pretty amazing! Paragliding is flight in it’s rawest, simplest and most pure form. The limited structure and absence of walls and a floor enables you to feel at one with your surroundings. While it’s often lumped in the same category as extreme sports such as skydiving and bungee jumping, it’s actually much more relaxing and appeals to a wide variety of people. Paragliding is definitely not as scary!
If you’re scared of heights, you might still feel comfortable with paragliding. What scares most people about heights is being close to the edge, or jumping off (e.g. jumping off a platform when bungee jumping). Paragliding in this regards, is different. You gently take off and are lifted into the air. And if you’re a first-timer, you’ll probably start with tandem paragliding, where an experienced pilot will take control from takeoff to landing.
Who Does This and Where?
Paragliding has always been a popular pastime in the mountainous regions of Western Europe. There are a number of places in France such as Annecy, Chamonix, Plaine Joux and Dune of Pilat to name a few. Other popular places include Interlaken in Switzerland, Tyrol in Austria, Tuscany in Italy, Oludeniz in Turkey and Algodonales in the south of Spain. At these locations you’ll see experienced paraglider pilots as well as tourism operators offering short tandem paragliding adventures for first-timers.
Other popular paragliding locations around the world include:
However, there are many paragliding enthusiasts who have their own spots where they go to escape the crowds and not only enjoy the thrill of flight, but enjoy the serenity of peacefulness of nature too.
How to get into Paragliding?
It’s a good idea to go on a couple of tandem flights with someone experienced and see if paragliding is something you want to invest your time and money in. If you’re keen on learning to paraglide, most countries and popular paragliding locations have providers who offer training courses. In comparison to other forms of human flight such as skydiving, the barriers to entry are low. Some courses can be conducted in as little as 8 days, where you are then free to fly by yourself.
While we are not against these courses, in such a short timeframe you may not get much experience in the wide range of conditions could be encountered. It’s a good idea after your training to continue flying with some experienced paragliders. They can help recommend places to fly in your local area which are suitable for your ability.
Many countries have paragliding clubs and associations where you can meet experienced pilots who are willing to offer advice.
- The USHPA in the United States in Australia
- The British Hang Gliding and Paragliding Association in the United Kingdom
It’s also a good idea to brush up on your meteorology knowledge. Learn about different clouds and their effects on thermals.
In most countries paragliding is considered a ‘self regulated sport’ with no licence required for solo flying. However, some clubs and associations may ask to see some form of certification stating that you have undertaken training before you can join.
You are also required to abide by the laws in your country regarding restricted airspaces such as flight paths, airports and military bases. Pilots should also avoid flying too low over buildings and roads.
How to Purchase a Paraglider
If your careful what you’re buying, there’s nothing wrong with buying a used paragliding wing, lines and harness, and navigational equipment. To be on the safe side, it’s a good idea to bring an experienced friend to view the equipment and check the wing, lines and harness for damage, or buy from someone reputable at your local association.
Two components which are worth purchasing brand new are the reserve parachute and the helmet. You’re life may depend on these at some point, it’s not worth purchasing damaged equipment to save a few dollars.
Paragliding wings are segmented into various EN ratings which act as a guide to help you purchase a paraglider which is suitable for your ability and type of flying you wish to perform. Those new to paragliding will start at the ‘first wings’ class (EN A rating) which are easier to manoeuvre and keep stable. The next level up from this is the ‘progression class which usually gets an EN B rating.
After this there are classes which offer high performance in certain characteristics such as:
How can paragliders fly?
You’ve probably been wondering what makes these pieces of fabric fly or why all of the gliders typically have the same shape or even how this flexible structure manages to stay aloft above the pilot’s head. Our focus on flight mechanics in this chapter will attempt to provide answers to all of these questions at the very least it will give you the basic understanding you’ll need to pilot this peculiar aircraft: a paraglider.
The paraglider’s aerodynamic profile
Let’s start by looking at the basic shape of our paragliders. We will demonstrate the importance of the wing’s profile the goal is to optimize its penetration through the air and reduce drag as much as possible.
We’re going to see what happens to the air have it flows over these three profiles: looking at the first profile, a simple plate, the molecules of air contained in the air stream are
completely blocked in the middle, the air that flows beyond the plate is turbulent which significantly increases drag. The airflow over this profile is similar to what happens when rowing a boat the oar needs enough force to displace water and have it displaces the water small swirls form behind it.
The second profile penetrates the air a lot better. As we can see here the result is much
smoother airflow, the molecules of airflow smoothly over the front of the profile. However, too much drag is still created by this profile.
The third profile has been improved so that the airflow is smooth from start to finish our profile will travel through the air with little resistance, thanks to its cambered shape.
It will also reduce drag by replacing the air in its wake. This is an ideal aerodynamic profile.
How a paraglider creates lift
If you were to cut the paraglide in half you’ll find this cambered shape along the entire wingspan, from the leading to the trailing edge. This is how manufacturers optimize the
wings penetration and movement through the air, but this doesn’t explain what makes a paraglider fly.
Let’s move on to a phenomenon that you’ve probably already heard of: lift.
Let’s take another simplified cross-section of our wing and observe what happens as air flows over its profile in flight: the angle created by the paraglider swing and the relative
wind is called the angle of attack. As the molecules of the air come into contact with the wing they are separated into two streams by the leading edge the first stream flows along the upper surface of the wing, the other along its lower surface even though. The upper surface is longer than the lower surface. Experiments have shown that both air streams reach the trailing edge at the same time: there’s only one way for the molecules taking the longer route along the upper surface to arrive at the same time, they have to accelerate.
Thanks to a principle formulated by Swiss mathematician and physician, Bernoulli, in 1738, we know that half the speed of a fluid increases its pressure decreases. In other words, the faster-moving air over the upper surface of the profile creates a low-pressure zone on top of the wing which is the source of lift. On the other side of the wing, air molecules push against the lower surface, creating a high-pressure zone. This is also a source of lift. About 3/4 of the lift results from the low pressure above the wing and 1/4 from the high pressure under it. Most of the lift occurs near the profiles leading edge.
This simplified explanation of what causes lift should help you understand why our wings fly.
Aerodynamic forces in a paraglider
Lift is thus created by the flow of air over the profile, but how is this phenomenon is sustained when there isn’t any wind? what is the paraglider’s motor?
In order to answer these questions will turn to the science of mechanics. This science deals with the action of forces on bodies. The forces we’re interested in are those that act upon the pilot and paraglider.
Let’s start with a simplified model of the low and high-pressure zones lift. This force acts upon a point known as the center of pressure. This point is merely an average of the lift forces acting upon the paraglider. When travelling through the air a paraglider encounters resistance and creates turbulence in its wake the force that opposes its forward movement is known as drag. Since these are the two main forces that act upon the profile we can add them: their sum gives us the resultant.
The altitude is the “fuel” of a paraglider
How do we obtain the relative airflow necessary to create lifts when there isn’t any wind? By simply transferring his weight to the wing, the pilot pulls it towards the ground forcing it to move forward through the air. This movement we call airspeed and this creates the relative airflow required to reduce lift.
Altitude, therefore, is the paragliders energy reserve and by using our weight to draw on his reserve we’re able to fly.
The angle of attack in a paraglider
As mentioned before the angle of attack is the angle at which the relative wind meets the profile this angle should not be confused with the angle to the horizon, learners attitude.
As it’s possible to have a relatively high angle of attack with the wing at any attitude, in normal flight the paraglider remains at a constant angle of attack and at a constant airspeed. The pilot can influence the angle of attack and thus the speed by using the brakes or speed system. The angle of attack and airspeed are very much related: if you change the
angle of attack the airspeed too will change until a new equilibrium is achieved. The angle of attack can be increased by applying the brakes, evenly this causes a corresponding decrease in airspeed. The greater the angle of attack, the more lift is produced, however,
more drag is also produced. If too much brake is applied then the smooth airflow over the profile cannot be maintained and the airflow breaks away from the top surface: This is known as a stall.
Being aware of the stall is very important when learning to fly since inadvertent stalls are very dangerous and should be avoided, always keep your hands high and make sure you feel good airspeed on your face whilst trying to avoid the stall.
Only when making the landing flare should you use deep brake inputs.
The angle of attack can be decreased using the accelerator system, as the angle
decreases drag is reduced and the speed increases. The glider continues to accelerate until a new equilibrium is found, the wing then stabilizes at this new speed and sync rate.
At low angles of attack, paragliders are more prone to collapse. This is why you should not use the speed system when close to the ground or flying in turbulent air.
Lift to Drag ratio in a paraglider
Let’s turn to the concepts of lift-to-drag and glide ratios. The lift-to-drag ratio is the angle at which the paraglider glides. These concepts will help you understand why a student barely manages to lift off from a slope. There are simply ratios that measure the glide capability of your wing, these ratios are obtained by dividing the horizontal distance covered by the vertical distance lost. In an example, 750 meters divided by 100 meters gives us a ratio of seven and a half.
As you may have guessed, the greater the horizontal distance is the greater this ratio will be and the longer your glide. This is called your lift-to-drag ratio, it’s a technical specification of your wing. The lift-to-drag ratio doesn’t change unless the wing is damaged.
We’ll see later on in the flight chapter that the wind or micrometeorology can influence the trajectory the distance covered will vary and in this case, would refer to its glide ratio.
Let’s go back to the example with our student: he can’t lift off because his lift-to-drag ratio is too close to the angle of the slope. The launches will need a hill whose slope is steeper than the lift-to-drag ratio of our wings.
Modern paragliders have a lift to drag ratio between six and ten to one. For reference, you can compare this with a lift to drag ratio of 15 to one for hang gliders and almost sixty to
one for sale planes.
Speed to fly in paragliding
Paragliders have a large speed range and knowing when to use these different speeds is very important. You have control of the speed with the brakes and the speed bar. This
is known as speed to fly.
Knowing to fly at the right speed depending on conditions or the site is the basis of safe and efficient piloting. Understanding different flying speeds will make you a better pilot, the correct speed and just the right timing makes it possible for the student to make a smooth landing.
As a general rule when in lift slow down and when in lift or headwind speed up. This increases your efficiency and prolongs your glide performance. Flying at trim-speed your glider will achieve its best glide angle in calm air. The pilot’s arms are high with no pressure on the brake handles. At this speed, the profile isn’t warped in any way and therefore create the least amount of drag flying like this will allow you to cover the maximum distance. Most modern paragliders have a trim speed of around 36 or 37 km/h. When learning the main reason for flying at such a speed is to accelerate before landing and build up energy that will eventually be converted into a flare. This makes a soft landing possible flying at trim speed also reduces the likelihood of problems caused by the wind gradient, such as inadvertent stalls or sudden altitude
last near the ground.
Applied the brakes approximately 30 to 40 centimetres to reach the minimum sink rate. The pilot’s arms are about level with his shoulders or just below and there is a positive pressure through the brake handles. Applying pressure to the brake handles will also improve your sensitivity to the wings movements and increases the internal pressure and
angle of attack of the wing which reduces the likelihood of collapses. Flying at min sink increases the angle of attack and significantly increases drag which reduces the ability to glide and consequently reduces the distance that can be covered. However flying like this gives you the slowest vertical speed, in other words, you sink at the slowest rate. You can
take advantage of this when flying in lifting air.
Note also that other than the landing flare it is never necessary to fly slower than the minimum sink rate.
This post is a transcription of the video “Learn to Fly” (Kitchen Productions)