system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do helicopters tilt in 4 directions with 2 propellers?
gpt
The propellor controll mechanism, called a swash plate, can change the angle of attack of the rotor blades depending on where they currently are. So you can just make the blades at one position have a higher angle of attack, so they'll produce more lift when they're in that position than if they're not, and so the helicopter tilts.