Which code is used for transponder identification?

Which code is used for transponder identification?

• A. Level 3 Anti icing
• B. Probes and sensors (Permanent)
• C. Squak Code / Identification
• D. Main and Emergency Battery

Answer: (C)

Transponder identification is done with a four-digit squawk code set in the aircraft’s transponder. ATC assigns a unique code to each flight, and when the transponder is interrogated by radar, it replies with that code. This lets controllers identify and track the aircraft on their radar screen. The term “squawk” comes from this practice of the transponder emitting its identifying code when asked. Sometimes pilots can use a quick-ident function to trigger a brief response for identification, but the actual identification is achieved by the squawk code itself. The other options describe icing systems, sensors, or power rather than identification codes, so they don’t relate to transponder identification.

Transponder identification is done with a four-digit squawk code set in the aircraft’s transponder. ATC assigns a unique code to each flight, and when the transponder is interrogated by radar, it replies with that code. This lets controllers identify and track the aircraft on their radar screen. The term “squawk” comes from this practice of the transponder emitting its identifying code when asked. Sometimes pilots can use a quick-ident function to trigger a brief response for identification, but the actual identification is achieved by the squawk code itself. The other options describe icing systems, sensors, or power rather than identification codes, so they don’t relate to transponder identification.