Usage Reasons
Relieves fatigue
Stable platform for instrument approaches
Improves control at high altitude
Allows you to carry out secondary tasks
Types
Single-axis
Two-axis
Three-axis
Single-Axis
Controls roll to maintain level wings
Manual turn control
Heading hold
Radio coupling
Two-Axis
Controls roll and pitch
Attitude hold
Desired rate of climb or descent
ILS coupling
Three-Axis
Controls roll, pitch and yaw