The term 'Controller Pupil' refers to a job description in the field of aviation. The job involves controlling the pupil's aircraft, which includes monitoring the aircraft's altitude, speed, and direction. The job also requires the controller pupil to communicate with other aircraft in the vicinity and to provide guidance to the pilot. The term 'IRIS' is an acronym for the International Radio Interference Suppression System, which is a system used to reduce radio interference from other aircraft.