Chapter 23. How Helicopters Work

Table of Contents

23.1. From the user to the transmitter
23.2. From the transmitter to the lower swashplate
23.3. From the upper swashplate to the rotor head
23.4. The rotorhead
23.5. Basic helicopter aerodynamics
23.6. How gyros work
23.7. GY-series gyro technical info
23.8. Yaw-rate gyro technical info
23.9. How ESCs work

(Please consult Chapter 31, Glossary for any unfamiliar terms)

23.1. From the user to the transmitter

The helicopter's control system begins at the joysticks of the transmitter. There are two common configurations for converting the user's joystick movements into helicopter movements:

Mode 1 (Asia, Australia, Europe, and some UK)
Mode 2 (US, some Europe and some UK)
Mode 3
Mode 4

Table 23.1. Mode 1 Stick Assignments

Joystick	Direction	Usage
left stick	u/d	fore/aft cyclic
left stick	l/r	rudder
right stick	u/d	throttle/pitch
right stick	l/r	left/right cyclic

Table 23.2. Mode 2 Stick Assignments

Joystick	Direction	Usage
left stick	u/d	throttle/pitch
left stick	l/r	rudder
right stick	u/d	fore/aft cyclic
right stick	l/r	left/right cyclic

Table 23.3. Mode 3 Stick Assignments

Joystick	Direction	Usage
left stick	u/d	fore/aft cyclic
left stick	l/r	left/right cyclic
right stick	u/d	throttle/pitch
right stick	l/r	rudder

Table 23.4. Mode 4 Stick Assignments

Joystick	Direction	Usage
left stick	u/d	throttle/pitch
left stick	l/r	left/right cyclic
right stick	u/d	fore/aft cyclic
right stick	l/r	rudder


22.2. Pirouetting figure eights		23.2. From the transmitter to the lower swashplate