What does it do when I push/pull a knob?

"A signature of Airbus autopilot Operation."

The push/pull operations of the FCU knobs are an ingenious and sophisticated feature exclusive to Airbus airplanes. This revolutionary design has transformed the way pilots interact with the flight instruments, creating an effortless human-machine interface. By simply pushing the knobs, pilots can give control to the autopilot to execute commands using its pre-programmed logic (also known as "Managed guidance mode"). Conversely, a pull operation signifies a manual command input from the pilot, where the autopilot executes the command in the most direct way possible (referred to as "Selected guidance mode"). For instance, when the heading knob is pushed, the autopilot will expertly follow its pre-planned flight path to the destination. Meanwhile, a pull of the same knob will command the autopilot to fly directly towards the heading input and maintain that heading until the pilot issues a new command. However, don't let the simplicity of this design fool you. The cost of these push/pull encoders is a testament to their value. It is estimated that one such encoder alone costs up to $150! Fortunately, with the miniFCU, you can experience this groundbreaking feature in its truest form at the price of ONE single push/pull knob.