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Description of the prototype Mosquito

The present Mosquito prototype is a small electric powered contra-rotating coaxial-rotor
helicopter. It is battery powered and has a very long flight time. The helicopter is
built entirely in carbon fiber laminates.


Key specifications for the Mosquito prototype:

Rotor: Weight: Motors (x2): Battery: Flight time: Control:

360 mm ........... (2 contra rotating 4-bladed rotors) 110 g ............ (ready to fly, 11v, 560 mAh battery) 2 W at 5 V ....... (11 g, efficiency 70%) 3 x 3.7 V, 560 mAh (Lithium polymer cells) 30 minutes 3 channels standard Radio Control

Because of the new Proxflyer concept, this helicopter is much simpler and has
much fewer parts than other model helicopters. The helicopter is passively stable
in hover and during forward flight and has no need for cyclic control. It is controlled
vertically, in yaw (rotation) and in forward and aft direction and it can be operated
with a standard RC transmitter and a V-tail mixer.

STABILITY: Most other "stable" helicopters, including toy helicopters from
Asia, achieve some kind of stability by utilizing centrifugal forces and gyroscopic
effects to keep the rotor and helicopter horizontal at all times, thus preventing it from
entering into oscillations or becoming unstable. The Proxflyer, however, uses a different
approach (patent pending). In stead of trying to keep the rotors in a horizontal plane, they
are arranged in an innovative way so that they do the complete opposite. Triggered by the
smallest horizontal movement, the rotors tilt up, creating a horizontal force stopping the
motion almost before it starts. The helicopter is kept at the exact same position relative
to the surrounding air. The Proxflyer concept gives the helicopter incredible stability,
but limits the maximum horizontal speed. The concept, without relying on centrifugal
forces alone, gives the rotors good and quick stability with respect to the rotor shaft
as well, and it will therefore promptly and smoothly let the helicopter move in the
same direction as it is tilted by the horizontally orientated tail rotor. As can
be seen in the video clips, it may be controlled very precisely.


Key benefits of the helicopter:

Absolutely stable without the use of any gyros or autopilots There are no servos, actuators, rods, links, gears or other moving part The whole helicopter is operated and controlled by 3 electric motors (2 motors for the main rotors and one extra motor for control) The rotor blades are encircled by a ring that supports and protects them It is very efficient, all the power is used to generate lift It is silent, the mechanical drives and the rotors generate no noise There are no vibrations It is safe

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