You can control aircraft and helicopters to the degree with realistic rudder pedal sets. The arrows on your keyboard aren't enough, because as a real simulation pilot you want to keep the rudder, the ailerons, or your tail rotor stable at exactly the right angle. With the amount of control you have over your device, you can create a completely new dimension in the gaming experience. In addition, landing an airplane is easier when you have better control over the rudder.