A
helicopter pilot manipulates the
helicopter flight controls to achieve and maintain controlled aerodynamic
flight. Changes to the
Aircraft flight control system transmit mechanically to the rotor, producing aerodynamic effects on the rotor blades that make the helicopter move in a deliberate way. To tilt forward and back (pitch) or sideways (roll), requires that the controls alter the
angle of attack of the main rotor blades
cyclically during rotation, creating differing amounts of
lift (force) at different points in the cycle. To increase or decrease overall lift requires that the controls alter the
angle of attack for all blades
collectively by equal amounts at the same time, resulting in ascent, descent, acceleration and deceleration.