
What happens when you brake a paraglider so much that the air speed falls below the minimum speed of about 25km/h?
The photo shows what happens when you pull so much brake that the air speed of the paraglider falls below its minimum speed. The glider stalls. Therefore we sometimes call the minimum speed of a paraglider the stall speed.
Don't do this while flying! Unless you are on an SIV- or acrocourse.
Older gliders can also enter a deep stall when you brake too much - see the chapter on Aerodynamics.

For a paraglider in the mountains, what wind speeds are considered safe to fly?
Wind results in turbulence in the mountains. While soaring on a ridge or at low dunes or flying in flatlands may be safe up to 4 Bft or a bit higher using a smaller mini-wing, in the mountains a wind speed up to 3 Bft (a maximum of 20 km/h) is the maximum for most pilots to fly safely. Strong winds are considered 25 km/h or over.
Standing on launch you see a rain shower approaching. Do you take off?
D is the only safe answer. You can never be sure that you have landed before the rain arrives, so C is risky. B is only partly true for light rains, but again you're taking a risk. A is not true, although flying in cloud is illegal in many countries.

What do we call the risers that are connected to the lines running to the leading edge of the canopy?
These are the A-risers connected to the A-lines.

Which pre-launch check is the most important?
Even though all newer harnesses have a safety feature to prevent you from falling out of the harness if you forget your leg straps, this is very uncomfortable and on an older harness it may be a fatal mistake. Checking lines and canopy is of course very important as well.
See the section on Launching in the Basic techniques chapter.

When is the best time to put your legs down during the landing approach?
D is the safest option. The others are either uncomfortable and unwanted because you can't use weightshift anymore, or unsafe if you are too late and land on your bum risking a back injury.

What is the weight of the fabric used to make paraglider canopies? (g/m2)?
Very light fabric strong enough for paragliders can be as light as 25g/m2. Very strong and heavy fabric weighs 40g/m2 or more.
At around 35g/m2, you can calculate that the weight of the fabric of just the top and bottom sail of a 25m2 canopy is a bit less than two kilos.

Why are the cell openings slightly pointed down?
The cell openings are positioned where the air flow hits the profile of the airfoil.

What are the minimum requirements for a safe take-off?
A straight headwind is not necessary, you can take off in a slight crosswind. The runway should be clear of cables and other obstacles, but a 500m radius is not necessary. It is however essential to be able to abort your launch, for example when you notice a knot in the lines.

How tight do you need to pull the leg straps of the harness?
The tightness of the leg straps does not influence the flying properties of the paraglider.
When the leg straps are too loose, after take-off you will find yourself hanging low under the seat and it's more difficult to get in the harness.
Too tight will hinder your movements during take-off, depending on the harness design. In some harnesses it will prevent you from getting into the seat fully.
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