Hang-glider
What's an Ultra-Light aircraft?
The origin of the ULA
A couple of decades ago, people fitted out a hang-glider with a little motor: the Ultra-Light Aircraft (ULA) had been born.
The construction
The Ultra-Light Aircraft is made of very light materials. The pipe-frame is made out of very light, but very strong, aircraft-aluminum. The wings are upholstered with a kind of synthetic draclon and they have an area of 15 square meters. An ULA has an average span of 10 to 11 meters, a height of +/- 2 meters and a length of approximately 6.5 meters. When the aircraft is empty, its weight is about 170 to 200 kilograms. Its maximum take-off weight is 400 kilograms. You've got ULA's that can contain 1 and ULA's that can contain 2 persons.
The motor of an ULA often is a small 2-cylinder 2-stroke motor. The 40 to 70 HP give the aircraft an average cruisespeed of 100 to 130 km/h. Of course this differs from type to type.
The instruments of the ULA are reduced to a minimum: besides the joystick and the pedals, the "cockpit" contains an altimeter, an air speed indicator, a compass and a temperature-meter (for the coolwater of the motor). Radiocommunication and navigation equipment, like GPS, can also be built in.
They used to have only a 2-axes control-system, to control the aircraft: "turning" by changing the main point. Changing the main point can take place by moving the wing, just like you've got to do by a hang-glider.
Hang-glider
Nowadays you've also got ULA's with a so-called 3-axes control-system. This is the same system as is used in sports planes, like Cessna's.
Then there are ULA's in which you sit in the open air. A flyers-overall and a helmet are in this case necessary. You've also got ULA's in which you can sit under a little hood, protected against the wind and possibly rain. Some types of 3-axes ULA's have the same luxury as little sports planes.
Ultra-Light
Aircraft (ULA), 3-axes
The Ultra-Light Aircraft is a very safe aircraft. The government has high demands related to the safety of the aircraft but also regarding the environment; an ULA has a low fuel-consumption and it makes little noise (approximately 60 dB). Because of its little weight and because of that its big possibility to glide, the aircraft is good manoeuvrable at low speed too. Because of the low touch-down speed, a rough landing doesn't immediately mean a lot of damage to the aircraft. An ULA is easy to control.
The aircraft is very light and because of that it's possible to built a parachute at the top of the aircraft. When the aircraft is out of fuel or something like that, the parachute can bring the aircraft and its passengers safely to the ground. Because of its little weight, the aircraft can also land on the ice. If you replace the gear with a couple of ski's you can even land in the snow or on the water!
Because of the size and the weight of the aircraft it's possible to defuse the aircraft and transport in a trailer behind your car.
To land or to take-off with an ULA, you only need a landing site of 50 to 70 meters. In Holland, however, taking-off and landing with an ULA is committed to very strict rules and can only take place at the special assigned landing sites. Another drawback is, that flying an ULA makes you very depending on the weather conditions. Flying when its very foggy or at night isn't possible.