WGM 21
| Aerotechnik WGM 21 | |
|---|---|
 WGM 21 in the helicopter museum Bückeburg |
|
| Type: | Small helicopters |
| Design country: | |
| Manufacturer: |
Aerotechnik, Development and Apparatebau GmbH |
| First flight: |
1969 |
| Number of pieces: |
1 |
The Aerotechnik WGM 21 was a single-seat helicopter from the German manufacturer aerotechnik, Entwicklung und Apparatebau GmbH in Frankfurt. The helicopter was designed as a quadrocopter , which is very seldom found . The aim of the designers was to produce a simply constructed VTOL aircraft that is easier to fly than a conventional helicopter and the price corresponds to that of a mid-range car. In addition, parking should be possible in the smallest of spaces.
construction
The WGM 21 was a single-seat helicopter with four diametrically arranged rotor arms, which made it possible to dispense with control surfaces or control rotors. The control around the vertical axis was carried out, as with a fixed wing aircraft, by pressing the rudder pedals, whereby the two rear rotor arms were pivoted around their own axis.
The four rotors were connected to the open frame by means of aluminum tubes. They were driven by a BMW two-cylinder boxer engine with 54 hp, which delivered its power via V-belts to a central deflection gear and from there to the four rotors via appropriately long V-belts. The pilot sat in an open bucket seat, which was arranged in the space frame in front of the engine and under the gearbox. He controlled the vehicle using a V-shaped joystick with throttle twistgrips and pedals.
According to the manufacturer, the advantages of the WGM 21 were:
- Immediate tax response and high tax stability
- Elimination of the cyclical rotor blade adjustment otherwise required for control
- Elimination of the complicated control kinematics
- Increased power surplus by saving the engine power otherwise consumed by the control rotor (torque compensation)
- Significant simplification of pilot training
If the four rotor booms were folded forward, only a footprint of 1.98 m × 2.18 m was required.
commitment
After successful tests at the "Testing Center for Aerospace" in Braunschweig, a provisional license to carry out test flights was granted.
Nothing is known about the further development of the project. Today the only existing prototype can be seen in the helicopter museum in Bückeburg .
Technical specifications
| Parameter | Data |
|---|---|
| crew | 1 |
| Rotor diameter | 2.60 m |
| Rotor area | 21.3 m² |
| Number of rotor blades | 4 × 2 |
| Rotor speed | Max. 1100 rpm |
| payload | 90 kg |
| Empty mass | 245 kg |
| Takeoff mass | 335 kg |
| Cruising speed | 115 km / h |
| Top speed | 125 km / h |
| Vertical rise | 4 m / s |
| Summit height | 2100 m |
| Range | 250 km |
| Engines | Two-cylinder boxer BMW 700 with 54 PS PS (Err kW) |
See also
Web links
- Photo retrieved from airliners.net on July 22, 2016
- Photos on bredow-web.de accessed on October 3, 2012
Individual evidence
- ↑ Flug Revue May 1969, p. 106