Flight
Airspeed
Vario
Above ground
Glide now
Bank
Task
Time
Time speed
Sailplane, no engine
Glider Thermals
A long white wing, a summer evening and no engine. Glide down to the airfield, then find a thermal under a cumulus cloud, circle with the birds and climb. Soar a ridge in a strong wind, ride the smooth wave behind a mountain and fly a cross country route round turnpoints as the sun goes down.
How to play
The glider sinks all the time, so every climb is earned. The autotrim flies the right speed for you, so it is easy to pick up. When the vario beeps, circle. Land on the mark, or out in an open field when you cannot get home.
Daily Drop · same task for everyone, every UK day
Daily Drop
Flights
Seven flights, each a little harder. The first is a simple glide home.
Keys: A and D bank, W and S faster and slower, Space airbrakes, T speeds up time, P pauses. On a phone, use the buttons under the picture.
Controls
Hold to flyHold A or D to bank; let go and the bank holds, so you can circle hands off. Level the wings to fly straight. W and S trim faster or slower. In lift the vario beeps: circle in it, and move the circle towards where the beeps are strongest. Hold Space for the airbrakes on the approach. T speeds up time on long glides; it drops back low down. P pauses, R flies again, N goes to the next flight.
Paused
How a glider flies
A glider has no engine. It is always gliding down through the air, trading height for distance: this one goes about 32 m forwards for every metre down at its best speed, near 100 km/h. Slower, around 75 km/h, it sinks most slowly, about 0.75 m/s, which is the speed for circling. Below about 70 km/h the wing stalls.
To stay up you need air that rises faster than you sink. On a summer afternoon the sun warms the ground and bubbles of warm air rise as thermals, topped by cumulus clouds where the moisture condenses. Birds circle in them too, and near the ground you can see the air shimmer. Thermals lean with the wind and are ringed by sinking air. Late in the day they fade.
Wind blowing onto a ridge has to go up and over it, so you can fly along the windward face and climb. Strong wind over a mountain can set up waves in the air behind it, like ripples behind a rock in a stream, marked by smooth lens shaped clouds. Wave lift is gentle but goes very high.
Between climbs the right speed depends on the air: faster through sink, slower in rising air. That is called speed to fly, and the green mark on the speed tape shows it. When you cannot reach home, you land out in a field: an open one, into the wind if you can, not trees, houses or water.
Autotrim
On to start with. It flies the speed to fly between thermals, the slow circling speed when you bank, a steady approach speed below 220 m and a flare at the very bottom. W and S nudge it faster or slower. Turn it off on the flight list for ×1.25: W and S then move the stick, and you hold the speed and flare yourself.
Scoring
Each flight scores up to 1000: 400 for the share of the route flown, 150 for speed against par, 250 for the landing, half for a soft touchdown and half for stopping near the mark or well inside the field, 100 for climbing well in thermals and 100 for smooth flying, with points off for each stall or overspeed. S is 900 or more, A 780, B 640, C 480. The total is then multiplied by the flight, from ×1 for Evening glide to ×3 for Sunset cross country. Land in trees, houses or water, or hit a hillside, and the flight is over. Your best score and grade on each flight is kept on this device.
Daily Drop
Every day there is one task for everyone, chosen by the date in the UK: out and return, a goal flight, a ridge run or a triangle, with its own thermals and wind. You get one scored try and a share card with your grade and five squares, one for each part of the score. After that you can practise it as much as you like. The next one arrives at midnight UK time.
I'm Arthur. I'm not a glider pilot, I just love watching sailplanes circle on a summer evening. The glider, the flights and the numbers are my own, simplified to make it fun to fly. If you know better, email me. If you like this, try carrying a load in Sling Load.
Questions
- How does a glider stay up?
- It is always gliding down through the air, about 1 m for every 32 m forwards at its best speed. To climb it needs air that is rising faster than it sinks: thermals under cumulus clouds, wind blowing up a ridge, or mountain wave.
- What does the vario do?
- It shows whether you are going up or down, counting the speed you could trade for height. With sound on it beeps faster and higher as the climb gets stronger, and drones low in sink. When it beeps, circle.
- What is the autotrim?
- It flies the glider at the right speed for you: the speed to fly between thermals, slow and efficient when you circle, and a steady approach speed low down with a flare at the bottom. W and S nudge it faster or slower. Turn it off and W and S move the stick directly for a x1.25 bonus.
- How is it scored?
- Up to 400 for the route flown, 150 for speed against par, 250 for the landing, soft and on the mark or well inside the field, 100 for how strongly you climbed and 100 for smooth flying without stalls or overspeed. That makes 1000, graded S, A, B, C or D, then multiplied by the level.
- What is the Daily Drop?
- One task a day, the same for everyone, chosen by the date in the UK: out and return, a goal flight, a ridge run or a triangle. You get one scored try and a share card; after that you can practise it as much as you like. A new one arrives at midnight UK time.
- Is this a real glider?
- No. It is my own simplified sailplane: 450 kg, a 14 square metre wing, best glide about 32 to 1 near 100 km/h, minimum sink about 0.75 m/s near 75 km/h and a stall near 70 km/h.