Just as Frank is about to be struck by the propeller of the Piper Chieftain Max is taxiing in the hangar, Mattie pulls a red handle on the cockpit floor, stopping the aircraft. What Mattie is pulling up is not a brake handle, but is in reality the handle for the emergency gear extension hydraulic pump and is not part of the aircraft's brake system at all.
When max is taxiing the aircraft inside the hangar, he is shown turning the control yoke to change directions. Doing this only moves the ailerons, which is not connected to the steering at all. The rudder pedals, along with differential braking and differential power from the engines, are what turn the nose of the aircraft during taxi.