Steering

A good and faithful reader (one of millions, I am sure) asked about steering on the ground. The Cessna 172 has a nose wheel steering system using a bungee cord system of some kind. It operates via the rudder pedals. Step on left pedal, turn left. It's not completely effective however, so the pilot supplements it with differential braking. Each of the main wheels has a disc brake. They are operated by stepping on the top of the rudder pedal. By pushing the top of the pedal you active the disc brake on that side. Push them both at once... stop straight. Push one or the other and you can make sharp turns if you have the power set right. Any time the pilot pushes the rudder pedals, the rudder also moves. Prior to take-off, the pilot puts his heels on the floor to avoid accidentally hitting the top of the rudder pedal and applying one of the brakes. On take-off as the air speed increases, the rudder begins to aid in steering down the runway, and the nose wheel bungee system becomes less effective. At take-off speed, the weight comes off the nose wheel and the rudder is solely responsible for controlling yaw. On landing, the pilot can hit the tops of both pedals (gently so the wheels don't lock and "flat the tire").