This system is used to transmit a variety of information from the aircraft to the ground.
Now implemented in many cockpits, this form of surveillance ensures that any miscommunication about altitude is detected before it becomes an issue. At LVNL we use the Pilot Selected Level (PSL), which allows the air traffic controller to check that the programmed flight level is the one the aircraft has been cleared to fly at.
Track label information
A track label – the green text on a radar screen – displays information from the system flight plan and data from the aircraft’s transponder. This includes the altitude entered into the autopilot and the one the aircraft is cleared to fly at, so that any difference between them can be seen at a glance.
