Thermalling is a vital skill for any paraglider looking to increase flight duration and distance. It involves using rising air currents---known as thermals ---to gain altitude and extend the flight. Mastering thermalling not only boosts your confidence but also allows you to enjoy paragliding in its purest form, as you soar gracefully, using nature's air currents to keep you aloft.
In this article, we will explore the essential thermalling techniques for paragliders, providing insights on how to identify and utilize thermals, refine your technique, and optimize your flight. We'll also suggest a few pieces of gear---such as a variometer , GPS flight computer , paragliding harness and helmet---that can make thermalling easier and safer.
1. Understanding Thermals and How They Form
Before diving into thermalling techniques, it's crucial to understand what thermals are and how they form. A thermal is a column of warm air that rises from the Earth's surface due to differential heating. It occurs when the ground warms up under the sun and heats the air above it, causing it to rise.
Thermals can be triggered by several factors, including:
- Solar Heating: The sun heats up the ground, which in turn heats the air above it.
- Topography: Features like mountains, ridges, and valleys can cause the air to rise when they interact with wind.
- Convection: As the warm air rises, it pulls in cooler air from the surrounding environment, creating updrafts.
By identifying and centering in on these rising air currents, a paraglider can gain altitude without the need for engine power, relying solely on the natural forces of the atmosphere.
2. Identifying Thermals: Visual and Environmental Clues
Recognizing thermals is one of the most important skills a pilot can develop. Here are some key clues to look for when searching for thermals:
Clouds and Cumulus Clouds
Cumulus clouds are a reliable indicator of thermal activity. These clouds form when rising warm air reaches the condensation level and cools, creating a visible cumulus shape. By flying towards these clouds, pilots can often find a strong thermal beneath them.
However, it's important to note that flying directly under the cloud can sometimes lead to turbulence, so it's better to position yourself slightly to the side or down‑wind of the cloud.
Birds and Insects
Birds, particularly thermal‑loving species like vultures, hawks, and eagles, are often seen circling in rising air currents. By observing their flight patterns, you can get a good idea of where the thermals are located. Insects---especially moths or butterflies---are also carried upwards in thermals.
Landscape Features
Topographical features such as hills, ridges, and valleys often create thermal updrafts. Mountains, for example, force air to rise as wind flows over them. Valleys may funnel air into a narrower column, enhancing thermal strength. Pay attention to how the wind interacts with the terrain to predict where thermals may form.
Gear tip: A lightweight variometer can help you confirm lift before you commit to a turn.
3. Entering the Thermal: Positioning and Technique
Once you've identified a thermal, the next step is entering it correctly. Good thermalling technique is essential for staying inside the thermal and maximizing your climb. Here's how to get started:
Positioning for the Thermal
- Fly Up‑wind: Approach the thermal from the up‑wind side. This will allow you to fly into the rising air and give you more time to find the centre of the thermal.
- Stay Calm and Smooth: Keep your movements smooth and avoid over‑correcting. Small adjustments to your control inputs will help you stay centred in the thermal.
- Check for Drift: As thermals can drift with the wind, it's essential to keep an eye on your position relative to the ground and adjust accordingly to avoid losing the thermal.
The 360‑Degree Turn
To stay inside the thermal, pilots must use a series of coordinated turns. The goal is to find the centre of the rising air and keep turning within it. The technique is often referred to as the "360‑degree turn."
- Start the Turn: Begin gently by pulling in the brake on one side. Maintain a shallow bank angle at first, gradually increasing as you enter the thermal.
- Maintain Consistent Bank: Keep the bank angle between 20--30 degrees during the turn. If you bank too steeply, you may lose the thermal; if you're too shallow, you might not get enough lift.
- Watch for a Lift Core: As you fly through the thermal, you'll feel a subtle increase in lift. The lift core is the centre of the thermal, where the strongest updrafts occur. When you feel this lift, stay centred by adjusting your turns accordingly.
Gear tip: Pair your 360‑degree turns with a GPS flight computer to track altitude gain and drift.
4. Fine‑Tuning Your Thermalling Technique
Once you've mastered the basics of thermalling, you can refine your technique to gain more altitude and extend your flight. Here are some tips for fine‑tuning your approach:
Adjusting Your Speed
The speed at which you fly can impact your efficiency in the thermal. Flying too fast may cause you to overshoot the centre, while flying too slowly can make you more susceptible to turbulence. A steady, moderate speed is ideal for thermalling.
Use of Weight‑Shifting
While braking controls pitch and roll, weight‑shifting can help you maintain a stable and consistent turn. Shifting your weight slightly towards the inside of the turn helps maintain the bank angle without over‑controlling with the brakes.
The Art of the "Double 360"
Advanced pilots sometimes use a "double 360," completing two turns within the thermal before checking lift and adjusting. This lets you sample lift more thoroughly and maximise time in the core.
Adjusting for Changing Thermals
Thermals are dynamic---they can weaken or shift during the flight. As you gain altitude, you may encounter weaker lift or changing wind conditions. Adapt your technique by looking for new thermals, checking altitude regularly, and adjusting your path if needed.
Gear tip: A comfortable paragliding harness with good load distribution reduces fatigue during long climbs.
5. Combining Thermalling with Cross‑Country Flying
Once you've mastered thermalling in local conditions, you can begin combining thermalling with cross‑country flying. By linking multiple thermals, you can cover vast distances, flying from one thermal to the next to gradually gain altitude and travel further.
Route Planning
Cross‑country thermalling involves choosing a route that will allow you to connect multiple thermals. Look for landmarks such as hills, ridgelines, and valleys---ideal places for thermals. Plan your route to ensure you have good landing options in case you need to descend.
Flying in a Group
Flying with other pilots can be beneficial when thermalling. Experienced pilots can lead you to good thermals, and flying in a group helps you learn by observing others' techniques.
Gear tip: A sturdy helmet is essential for group flights, where close proximity increases the risk of minor bumps.
6. Common Thermalling Challenges and How to Overcome Them
Thermalling, like any other aspect of paragliding, comes with its own set of challenges. Here are some common issues and how to deal with them:
Turbulence
Turbulent air can cause a bumpy ride, but it's important not to panic. Turbulence often indicates that a thermal is close, though it can make thermalling more difficult. Stay smooth with your inputs and give the glider time to settle as you enter stronger thermals.
Lost Thermals
It's common to lose a thermal, especially as they move with the wind. If you lose one, don't panic---simply circle back and try to locate a new one. Pay attention to wind direction and use landmarks to help find fresh lift.
Gear tip: An accurate variometer with audio alerts can warn you early when lift is fading.
Conclusion
Mastering thermalling is one of the key skills for paragliders seeking to extend their flight and improve overall performance. With practice, you can learn to identify thermals, enter them with precision, and fine‑tune your technique for maximum altitude and enjoyment. The combination of the right environment, good technique, appropriate gear, and patience will allow you to soar higher and farther, enjoying the freedom and beauty of the sky. Stay focused, stay calm, and let the thermals carry you to new heights!