One other effect of this air travelling up the hill is that it displaces the air above the slope which otherwise would not need to rise. This has a two-fold effect in that it increases the size of the lift area for us to fly in and also the wind speed at the ridge.
Still not convinced? Then take a look at some of the video's on the Slope Soaring links page
We fly in this rising air and therefore need to choose a suitable model to suit the lift conditions on the day. Generally speaking the parameters are pretty wide and a couple of well chosen models will cover virtually all conditions.
Low wind speed equals less lift requiring a more efficient glider, or a floater.
High wind speeds, equals more lift and requires a glider designed for slope soaring.
Even higher wind speeds, and you can even fly a house brick or if you're really into it, a thousand quid glass ship!
In the end there's no need to worry about what sort of glider you need, because if you only go to the slope when it's too windy to fly from the club strip, then our local slopes will be 'working' fine and you will only need one model, a Zaggi !
Restrictions, what restrictions?
Well there aren't any really, it's simply a question that in order to maximise our flight log we must simply choose the model, and the discipline to suit the wind strength on the day you want to go flying. Having flown most types of R/C models, I've found that gliders in the form of slope soarers do offer the widest range of practical flying speeds and therefore the ability to cope with the wind. They are after all, designed that way. You can fly a slope soarer from zero wind speed right up to the point of being blown over or if you can't stand up then stand-back from the slope or hide behind something!