Definition
In a helicopter, the action of raising or lowering the collective control lever to change the pitch angle of all main rotor blades simultaneously and by the same amount, which increases or decreases total rotor lift.
Plain English
Pulling up or pushing down on the collective lever changes the angle of every main rotor blade at the same time, making the helicopter climb or descend.
Context Anchor
In the Instrument Flying Handbook, this appears during helicopter instrument takeoff, where the pilot must raise the collective smoothly while keeping the helicopter controlled by instruments.
Derivation
Collective' comes from the Latin 'colligere', meaning 'to gather together'. The name fits because this control gathers all the rotor blades into one shared pitch change at once, rather than adjusting them individually like the cyclic does.
Why Pilots Care
It governs vertical speed and power application, which must be managed precisely when visual references are absent.
Intuition Check
Pitch here does not mean the helicopter nose moving up or down. It means the angle of the main rotor blades changing together.
Example Sentence 1
During the instrument takeoff, the pilot applied a smooth collective pitch movement to lift the helicopter into a stable climb.
Example Sentence 2
Smooth collective pitch movement helped maintain altitude during the instrument turn without over-torque.