Counter Intuitive Helicopter?

Coaxial rotor systems are complex and difficult to understand. Their disadvantages include high weight and maintenance costs. Even so, the Russian Kamov KA 26/226 and KA-32 have become famous and successful using this technology. Even in western Europe, they are known as reliable. These helicopters are not ‘lightweights’, and consequently a little additional weight does not affect their performance. 

As a Russian helicopter designer once said, ‘in nature everything that flies has two wings. So we build our helicopters with two wings (rotors)’. The advantages of this are easily explained: in a normal helicopter, the tail rotor alone uses 30% of the power. By omitting it, all available power can be used for lift. There are no torque changes when changing power, and hovering is much more stable. The helicopter is also easier to handle than conventional models.

This technology has not yet been used for very light helicopters, because the manufacturers have found the conventional main/ tail rotor principle sufficient...