Good question! Just like any other aircraft, it is the gliders wings that produce the lift to keep the aircraft in the air.
Gliders are very cleverly designed to have long wings and be very light in weight. This is so the wings can generate big amounts of lift to hold a very light glider in the air. Once a glider is airborne, it will fly sightly nose down and gradually drift back down to the ground – similar to a thrown paper airplane.
There are various types of gliders that can glider for longer than others. This depends on wing structure, weight and weather conditions. Dual seated training gliders typically have a glide ratio of 25:1 (you’ll lose 1 foot of height for every 25 feet travelled forward). More high performance gliders can have a glide ratio of 60:1 – wow!!
How does a glider stay in the air when it doesn’t have an engine?
For a glider to stay in the air for longer, the pilot has to hunt for areas of lift or rising air to help the glider gain height. There are several ways of finding lift:
As wind blows against a hill or a mountain side, the air is pushed up and over the top.
This creates a band of rising air in front of the hill that glider pilots use to help gain height.
A glider pilot will go back and forth along the hill side in the band of rising air to climb higher and higher, this is called Ridge soaring.
Have you seen birds of prey circling without flapping their wings?
They have found a thermal.
A thermal is a column of warm rising air. If the air rises quicker than the glider or bird is going down, they will be pushed up. Birds will feel a push under their wings from the rising air and will start circling to stay in the column to gain height, same with gliders.
As the air rises it will cool, the moisture will then condense to form fluffy cumulus clouds (these tend to be handy markers for the pilots).
A glider pilot can then leap frog from thermal to thermal to stay in the skies for longer.
As wind flows over a mountain, the air gets forced up and over like ridge lift. However wave lift occurs at higher altitudes with taller mountains. The airflow will then oscillate behind the mountain causing smaller waves. Often, the sign of wave lift is distinguished by a “wave lenticular” cloud formation.
By facing the glider in the strong upward draughts of the oscillation, the glider will be carried upwards many thousands of feet and can then glide for hundreds of miles.
Can you control a glider?
Yes, most definitely!
I was once told, ‘Gliding is very similar to a free-wheeling bicycle going down hill. As you go down hill with your feet off the pedals, you’re still in full control of the bike. You’re just not powering it because it is gravity pulling you down the hill’. The same with gliders.
Now if you point your free-wheeling bicycle uphill you will start to lose energy, as a result the controls will become sloppy. Again same with a glider.
In conclusion, gliders will need to point slightly downwards to maintain speed and full control. If a glider doesn’t have speed or airflow over its wings, the wings will no longer produce lift and the controls will become less effective.
How does a glider get into the skies?
There are several ways a glider can be launched into the skies: by bungee, aeroplane (known as an aerotow), winch or by car. Aerotow and winch are the most common methods in the UK.
An aerotow can tow a glider up to an altitude of the pilots choice, typically 3000ft to give the pilot more flying time. A winch launch is where a glider is attached to a winch (situated at the opposite end of the runway) via a metal cable. On the signal the glider is pulled forcefully into the air to roughly 1500ft (typical length of the winch cable) before releasing to go off soaring.
What’s the best weather for a gliding experience?
The best day for a gliding experience is typically when it is warm with virtually no winds. Remember I said before, we like to see the sky full of little fluffy cumulus clouds that are white on top and a shade darker underneath. They are ideal markers to tell us where the thermals are.
We do not like to glide in rainy or strong windy conditions, as it becomes difficult to fly and therefore dangerous. This is why we always ask you to contact the airfield on the day of your experience to double-check weather conditions. If the weather isn’t suitable to fly then your flight will be rearranged for another date.
How much are gliding lessons?
Gliding is definitely one of the cheapest forms of flying with a winch launch flight costing around £50 and an aerotow flight costing about £75. We do also offer half day gliding courses where you can enjoy multiple flights and get involved helping run an airfield!
Ever fancied soaring with the birds? Why not check out our range of gliding experiences! The perfect gift to treat yourself or a new experience for a loved one to try!
Lift illustrations sourced from Dartmoor Gliding Society