Heading control measures the current heading, subtracts the set heading, and applies rudder to bring the difference back towards zero. Speed control does the s

Heading control measures the current heading, subtracts the set heading, and applies rudder to bring the difference back towards zero. Speed control does the same with speed sensors and the throttle. That's why aircraft autopilots have been around since 1912. https://en.wikipedia.org/wiki/Autopilot https://en.wikipedia.org/wiki/Autopilot