Soaring FAQ

Can anyone fly a glider in Australia?

To fly solo, you must be older than 15, be a member of the GFA and a recognised gliding club and have been cleared to fly solo by a qualifed instructor. The health requirements are similar to that for getting a driver's license. There is no mandatory upper age limit for flying a glider.

To fly cross-country, you must have gained your C Certificate which includes tests for outlandings and retrieves.

I don't know if gliding is just for me. How can I have a trial flight?  

Trial flights are officially called 'Air Experience Flights.' You can get a trial flight on most days at the club. Just give the manager a ring and arrange it. Alternatively, if the weather is good, you can just turn up and take your chances.

What's the difference between a glider and a sailplane?

Not much really. Hang gliders, paragliders and sailplanes are all gliders. At the start, all non-powered aeroplanes were called gliders. The pilots would jump off hills or be catapault-launched off the edge of a hill. Then, as the performance of the more advanced gliders increased to the point where they could stay up or climb in ridge lift or climb in thermals, these advanced gliders were called sailplanes.

There are many ways of measuring sailplane performance but perhaps the most common is glider ratio or the ratio of lift to drag. This measures how far a glider will travel for every unit of height lost. So if your glider has a glider ratio of 30:1 and you are a 1,000 metres up, you can glide about 30 kilometres before you have to land.

In fact most club sailplanes have a glide ratio of well over 30:1 and many are over 45:1. Compare this with paragliders which are generally less than 10:1 and hang gliders which are generally less than 15:1. In most instances, calling a sailplane a glider will not matter at all.

 

How do sailplanes get airborne?

In Australia, and at Lake Keepit, there are two main ways to get into the air. The first is where the sailplane is towed up by a light aircraft with a short tow rope. Both the glider and the tow plane have special tow releases holding the rope. The sailplane releases when it has been towed to the desired height. The other principal method of lauching is with a powerful winch. Once again, a special tow release is used at the glider end of the winch rope. When the glider is at the top of the tow, either the pilot releases the rope, or the release automatically lets go of the rope.

Sailplanes are also launched by car-towing and even by bungee launching… which was the first method developed to launch gliders on slopes. Many modern sailplanes are Self Launching. That is, they have a small motor concealed in the fuselage behind the wings which can be used to launch the glider and to get you back home if the lift or your courage fails.

The advantage of towing up behind an aeroplane (aerotowing) is that the sailplane can release at the height and location it wants to… hopefully in a thermal. The main disadvantage is cost.

The advantage of winch launching is cost. Perhaps half that of aerotowing. The disadvantage is that the release height and location are more or less fixed, and it not quite as reliable a way of finding a thermal.

 

How is a glider controlled?

Almost all sailplanes are steered with the same "3 axis" controls as any aircraft. A control column or joystick controls the elevator for pitch control, and the ailerons for roll control. There are pedals to control the rudder for yaw control. In a sailplane, because the wingspan is so large, the pilot uses more rudder than in a powered plane and glider pilots have to learn to accurately coordinate the use of all three controls. Most powered aircraft don't use the rudder to any great extent, and pilots are often surprised at the amount of rudder required in a sailplane.

All sailplanes also have very efficient air-brakes which are used to control the glide or descent angle when landing. Higher performance sailplanes have retractable undercarriages to reduce drag and flaps to optimise performance in fast and slow flight regimes.

 

What holds a sailplane up in the air, when it has not got an engine?

As long as a sailplane keeps moving forwards, lift generated by the wings keeps it up there, just as with a conventional powered aircraft. The sailplane is slowly sinking as it moves forwards through the air… in fact sinking far more slowly than powered aircraft.

Typically, a sailplane sinks at around 600mm per second. Updrafts in the air called thermals, commonly under clouds can rise up much faster than 600mm per second and lift a glider up to cloud base faster than almost any powered aircraft can climb… but even in this rising air, the glider is still sinking relative to the air it is flying in.

Lake Keepit is primarily a thermal site. At other sites, lift is found on ridges and mountains, where the air is deflected upwards by the shape of the terrain. Lift is also found in wave lift which is the same thing as ridge lift, but more so! Altitudes of over 8,000 metres are common in wave lift, and the record is much higher than that.

 

How far can you fly? And how fast?

At Lake Keepit, pilots regularly fly over 750 km and land back at base. The longest distance flown from Lake Keepit is over 1100 km. On flights like this, the sailplane will normally average over 100 km per hour… much faster than a car can travel. The world distance record is unofficially over 3,000 km, flown in wave lift in South America. Most sailplanes can easily achieve speeds of over 250 kph in a straight line.

 

Is there any purpose to sailplanes? Can you do anything useful with them?

You can have a lot of fun! And it can be argued that when people have fun, it benefits society as a whole. So in that case, sailplanes are useful as a benefit to society. Apart from that, sailplanes are just very nice toys… and not just for the boys either.

 

So what happens if the thermals run out?

Not much! Normally, towards dusk, the strength of thermals gets so low that a sailplane can't stay up and sometimes a sea breeze or storm may kill the lift. Then the sailplane gently sinks towards the ground. With good judgement, sailplane pilots try to stay high towards the end of the day and final glides can be a hundred kilometres or more.

In almost all cases, either by judgement and experience, perhaps with the aid of a sophisticated glide computer, the pilot works out how much altitude is needed to return to the airstrip, and makes sure the aircraft has plenty of height to perform a normal landing circuit. In fact, gliders rarely land out.

That being said, gliders are designed to land on quite rough paddocks and Lake Keepit is surrounded by many suitable airstrips, farm strips and paddocks for an outlanding. On many of these an aerotow retrieve is possible. If not, the glider is taken apart and put in its trailer for the trip home by road. In many cases, the cost of the road trip is higher than the cost of the aerotow to the unfortunate pilot who has to shout dinner and a beer or two for the helpers.

 

I have seen pictures of old wooden gliders called hang gliders. Is this right?

In German, a "hang" is a slope. So a "hang gleiter" is literally a slope soarer. The gliders flown by Otto Liliienthal were flown from hills, and the pioneer sailplane pilots on the Wasserkuppe initially launched from hills, the slopes of which were called names such as the South-West Hang or Pelzner Hang… thus "Hang Gliders".

In fact the gliders flown by Otto Lillienthal used weight shift for control, exactly as modern hang gliders do, whereas all but the very earliest gliders at the Wasserkuppe used traditional control surfaces like modern sailplanes.

 

Does anybody regulate sailplanes in Australia?

Of course! CASA, the government body charged with regulating aircraft in Australia, delegates responsibility to the Gliding Federation of Australia (GFA) and the Hang Gliding Federation of Australia (HGFA) which looks after hang gliders and paragliders.

Sailplanes are certified aircraft, just like any light aircraft or commercial aircraft. This means that the manufacturer certifies that the aircraft has been built to internationally agreed standards. In fact sailplanes are built to higher strength limits than most general aviation aircraft.

The GFA has been in existence many years and has efficient programs for glider maintenance and inspection as well as pilot and instructor training.

 

So how safe are sailplanes?

The most dangerous sport in Australia is supposedly rock fishing. Horse riding follows close to that. Gliding is an adventure sport, but it is not really an adrenaline or an extreme sport. Gliding is as safe or safer than general aviation, and ranks with a big group of sports not generally considered unsafe such as scuba diving, mountain climbing and so on. Sports such as rugby football, motorcycle racing and horse riding are several orders of magnitude less safe than sailplanes.

 

What are sailplanes made from?

What have you got?! Initially, just like the aircraft of the time, gliders were made from wood and doped fabric. You've all seen highly aerobatic light aircraft made from these simple materials… they are perfectly strong enough.

However with sailplanes, the search is for greater efficiency. More speed, less drag. Wooden construction became a limited and expensve way of building gliders, so in the late 60's when fibreglass appeared, it was immediately embraced by glider manufacturers and the resulting gliders rapidly outclassed their wooden predecessors.

There are gliders made from aluminium. This is especially the case in the old Eastern block countries were many military pilots were trained ab-initio in gliders. So their gliders were built exactly as you would build a military aircraft. Generally, the performance is not as good as most later wooden and almost all fibreglass sailplanes and the maintenance is high.

Now, almost all gliders are made from either fibreglass or carbon fibre… normally a mix of both. Carbon fibre where it is needed, and glass fibre where the strength of carbon is not warranted.

 

What about owning a glider?

You can own your own glider but in fact there is no need to buy your own glider. Almost all gliding clubs own a range of gliders, single and two seaters which are available to club members for hire by the minute, the day or the week. You need to hold a recognised gliding qualification and will need a check flight, but there's no need to own your own plane.

One good thing about this is that you can hire a glider at almost any club in Australia and when you go overseas.

 

What's the cost of a sailplane?

That depends on what you want to buy! In spite of what you may think, gliding is not an expensive sport. You can buy a competitive second hand sailplane for less than $15,000. There are a lot of older gliders around and therefore a lot of competitions for gliders of this age and performance. 

You could also buy a 1/2, 1/3 or 1/4 share in a glider for a lot less. The annual costs are quite low. Each glider has to be inspected annually, the so-called "Form 2" inspection. But since these inspections are often done by qualified club volunteers, annual costs can be as low as a few hundred dollars. (Compare this with the costs of yachting!)

New gliders can be anything from $150,000 upwards. There are a number of excellent ultralight sailplanes being built, mainly in the old eastern block countries where they have a good tradition of aircraft and composites work which cost a lot less than this. It remains to be seen what effect this will have on the sport.

 

If you want to find out more about gliding and sailplanes, have a look at the information section of this site for book titles and links to other gliding related web sites.