What is an ATC transponder?
Summary. Transponders are used to give information to ATC about an airplane’s location in space and in most cases its altitude as well. This instrument can identify an airplane uniquely and serves the main purpose of helping ATC keep airplanes separated, all in the service of safety in air travel. Transponders first came into use to enable military authorities to identify friendly aircraft, which transmitted a coded signal when interrogated by military radar. This was known as IFF (Identification Friend or Foe). Subsequently, transponders have come into widespread use in civil as well as military aviation.
What is the purpose of the ATC system?
The primary purpose of the ATC system is to prevent a collision involving aircraft operating in the system. Pilots communicate with air traffic control (ATC) primarily through radio transmissions using Very High Frequency (VHF) radios. This communication is essential for maintaining the safety and efficiency of air traffic, particularly in busy airspaces.