Concept and development
The two-seated sports aircraft belongs to the Ultralight Class (UL) with a maximum take-off weight of 450 kg (992 lbs).
While the conventional UL helicopter is equipped with a single rotor plane and a tail rotor, the coaxial UL helicopter CoAX convinces with its two counter-rotating rotor planes:
- very quiet hovering characteristics,
- the conversion of the total engine power into the lift and
- a noise reduction of about 15-20% compared to the conventional model.
Both UL helicopter variants are built on an identical base, only the tail boom and the drive train differ.
The ultralight sports aircraft are powered by an engine from the Belgian manufacturer ‘D-Motor’, model LF 39, which is connected to the rotor mast using a special clutch. The supporting airframe is manufactured as a rivet frame construction and the cabin is fully made of CFRP. Both versions have a double control, two seats with belts and an instrument panel with the necessary instrumentation. The helicopter stands on a skid landing gear.
The rotor blades specially developed for our UL helicopter consist of CFRP composite material, which is processed in an expensive manual procedure applying a special laying technique. The carbon fibres provide extremely high stiffness and strength at low weight, which is why they are preferably used in the aerospace industry. The in-house developed rotor blades thus provide very high bending and torsional stiffness. The rotor blades are individually interchangeable.