FLIGHT CONTROLS
Four basic flight controls
1.
2.
3.
4.
Cyclic pitch control
The collective pitch control
The throttle
The antitorque pedals
• The collective and cyclic controls the pitch of
the main rotor blades
COLLECTIVE PITCH CONTROL
• The collective pitch control, located on the left
side of the pilot’s seat, changes the pitch
angle of all main rotor blades
• Collective pitch control is raised there is a
simultaneous and equal increase in pitch
angle of all main rotor blades
• Done through a series of mechanical linkages
• As the Pitch angle increases,
Angle of attack increases,
Drag increases, and
Rotor r.p.m. decreases
• In order to maintain a constant rotor r.p.m a
proportionate change in power is required to
compensate for the change in drag.
• Accomplished with the throttle control
THROTTLE CONTROL
• The function of the throttle
To regulate engine r.p.m
• If the correlator or governor system are not
installed, the throttle has to be moved
manually to maintain r.p.m.
CORRELATOR
• is a mechanical connection between the
collective lever and the engine throttle
• When the collective lever is raised, power is
automatically increased and vice versa.
GOVERNOR
• is a sensing device
• senses rotor and engine r.p.m.
• makes the necessary adjustments in order to
keep rotor r.p.m. constant
• are common on all turbine helicopters and
used on some piston powered helicopters
• Some helicopters do not have correlators or
governors and require coordination of all
collective and throttle movements
COLLECTIVE PITCH / THROTTLE
COORDINATION
• When the collective pitch is raised, the load
on the engine is increased in order to maintain
desired r.p.m.
• The load is measured by a manifold pressure
gauge in piston helicopters or by a torque
gauge in turbine helicopters
• The collective pitch is the primary control for
manifold pressure, and the throttle is the
primary control for r.p.m.
• The collective pitch control also influences
r.p.m., and the throttle also influences
manifold pressure
CYCLIC PITCH CONTROL
• tilts the main rotor disc by changing the pitch
angle of the rotor blades in their cycle of
rotation.
• The rotor disc tilts in the direction that
pressure is applied to the cyclic pitch control
• If the cyclic is moved forward, the rotor disc
tilts forward
• the rotor disc acts like a gyro
ANTITORQUE PEDALS
• located on the cabin floor by the pilot’s feet
• control the pitch, and
• therefore the thrust, of the tail rotor blades.
• The pedals are connected to the pitch change
mechanism on the tail rotor gearbox
• Allow the pitch angle on the tail rotor blades
to be increased or decreased
• Antitorque pedals compensate for changes in
torque