Expert: Mike Hicks - 3/23/2010

Question
Greets Sir

In a tandem rotor helicopter, how do the rotors avoid knocking each other since they are so large and pretty close to each other?
Because it has two horizontal rotors, does this mean that the tandem rotor has 2times the lift power compared to a single rotor gets?

Sir, you told me before that a helicopter blade has an airfoil shape. Does this mean that the high pressure below the blades when it is pitched lifts the helicoper?
Prashanth

Answer
The rotors don't mesh because the individual gearboxes are synchronized.

Lift is a measure of Airfoil size, shape, speed, so with 2 big rotors, Yes more lift is achieved.

Lift is achieved when a higher pressure seeks a lower pressure, by changing the pitch (angle of attack) of the blades you change the pressure therefore increasing lift..up to the point where the critical angle is reached and the airfoil or blade stalls.

hope this helps