There is more to life than 172 'planes'.
An aircraft is a vehicle which is able to fly by being supported by the air, or in general, the atmosphere, of a planet. Examples include balloons, airplanes and helicopters. Objects which fly but which are not supported by the air, such as most rockets and missiles, are not aircraft. Unmanned vehicles are often called drones, remotely piloted vehicles (RPV) or unmanned aerial vehicles (UAV).