I have a old toy helicopter which is currently not working. It has coaxial blades in order to lift it. It has a fixed shaft. Both blades have separate motor which helps them to rotate. I have very little knowledge about this field but while doing my research on this i found on Radio-controlled helicopter (wikipedia) that "Most models are fixed-pitch, i.e. the collective pitch of the blades cannot be controlled, plus the cyclic control is only applied to the lower rotor".
Is it possible that by increasing the speed of lower blade and simultaneously decreasing the speed of the upper blade i could make the helicopter move forward. Please guide me.