Bob Adamson's Gliding Pages

This site is likely to be always under construction!

Until recently I was an active glider pilot and a member of the Scottish Gliding Centre, the largest club in Scotland, at Portmoak airfield near Kinross. I took up the sport many years ago in my early twenties but like many others dropped out when marriage and career took up too much of my time. When I returned to Scotland after living and working for quite a few years in the south of England I discovered by chance that one of my next-door neighbours was an instructor at the SGC. He instructed on the club's regular summer 'ab-initio' courses which I joined - I was cleared for solo on the 1st of April the following year, a curiously appropriate date, and I flew there fairly regularly. I have recently dropped out a bit to allow time for other things (for safety reasons you need to maintain a reasonable level of currency) but who knows - I might return to it some day.

Gliding is unusual in that although it could hardly be more of a solo sport, it engenders a real club atmosphere because you just can't do it alone (strictly speaking that's not true - a self-launching motorised glider can be operated single-handed but most people don't have one of those). It takes a team to prepare gliders for flight, man the winch or tug aircraft, run the launch-points and generally help around; and although the club has a small professional staff most of the flying-related activities are handled by the members. All sorts of people take up gliding, from teenagers to the retired, both sexes. No especial level of fitness, strength or technical ability is needed to fly a glider. If you're fit enough to drive, you're fit enough to glide and just as you don't need to know anything about mechanics to drive a car, so you don't need to be an aeronautics expert to fly a glider.

To the newcomer it's difficult to see how a glider can stay up at all without an engine. Aircraft wings generate lift by the action of an aerofoil moving through the air and in a powered aeroplane the energy for this comes from the engine pushing them along. In a glider the energy required to do this comes from the potential energy due to its height and so it follows a gentle downwards path rather like a cyclist freewheeling down a hill. The pilot can control its direction and rate of descent but averaged over time the glider must descend through the mass of air it is flying in. (Although it looks and is very sophisticated, a glider has a lot in common with a paper dart.) The air is seldom still however and if you can arrange it so that the glider spends its time in air which is rising at least as fast as the glider is descending through it then the glider will stay airborne. Experienced pilots can climb tens of thousands of feet and fly for hundreds of miles using these rising air currents. More about this here.

I used to own a glider of my own, a Glaser-Dirks DG-202 which is a flapped single-seater with a 15 metre wingspan. In addition it has a set of wingtips which convert it to a 17 metre span so it is really two gliders for the price of one. The reason for the tips is that gliders are classified for competition purposes and although for gliding performance generally speaking the longer the wings the better, there are occasions when 15 metres is the limit. Its a fairly old machine (1981) since new gliders are VERY expensive, and you can read a little about it here. Gliders don't really wear out very quickly although of course they tend to get knocked about a bit over time. As in many areas of technology, the steep part of the learning curve for glider design came quite early on and although my glider is around 30 years old (manufactured in 1981) there are no present-day gliders in the same class with any more than about 10% better performance. There are many measures of glider performance depending on quite what sort of flying is being considered. My DG-202 has a minimum sink rate of about 100 feet per minute in still air and a best glide angle of approaching 45:1 which means that in favourable conditions it can fly about 8 miles for a loss of only 1000 feet of height (this is theoretical and maybe about two-thirds of this would be a safer bet). Gliders are capable of much greater speeds than is generally appreciated and although I generally fly at around 45-60 knots (a knot is about 1.1 miles per hour), its maximum speed is 146 knots which is about 160 miles per hour. Gliders are also much more robust than their graceful appearance might lead you to believe and can be flown in windy conditions which would ground most light aircraft. Most are also capable of at least restricted aerobatics - my DG-202 is rated for chandelles, loops, stall turns, spins and lazy-eights.

You might like to look at some of my gliding-related photographs here or or maybe the Scottish Gliding Centre's website.

Page last updated by on 27/12/2015