yes, you can use a gyro on an airplane. It is a small box that plugs between one servo and the receiver. It controls the servo for you. the most common application in a plane is on the rudder. With a gyro, the rudder is automatically moved to keep the airplane going straight down the runway on takeoff. Many gryo's also have another wire that plugs into another receiver channel. this channel is used to turn the gyro on and off or adjust its sensitivity.