Which TACAN mode provides range and bearing to a ground station?

Which TACAN mode provides range and bearing to a ground station?

• A. Air-to-Air mode
• B. Receive mode only
• C. Transmit-only mode
• D. Transmit/Receive mode provides range and bearing to the ground station

Answer: (C)

TACAN gives you two pieces of navigation data to a ground station: azimuth (bearing) and range. Azimuth comes from the station’s rotating directional signal, while range is obtained from DME, which requires a two-way exchange: your aircraft interrogates the ground station and the station replies. That two-way capability only exists when TACAN is in a transmit/receive mode, so the system can both send the interrogation and receive the response. If you were in air-to-air mode, you’d be talking to another TACAN unit, not a ground station. If you were in receive-only, you wouldn’t send the interrogation and thus couldn’t obtain range. If you were in transmit-only, you’d send interrogations but never receive the ground reply, so you wouldn’t get range either. The mode that provides both range and bearing to the ground station is transmit/receive.

TACAN gives you two pieces of navigation data to a ground station: azimuth (bearing) and range. Azimuth comes from the station’s rotating directional signal, while range is obtained from DME, which requires a two-way exchange: your aircraft interrogates the ground station and the station replies. That two-way capability only exists when TACAN is in a transmit/receive mode, so the system can both send the interrogation and receive the response.

If you were in air-to-air mode, you’d be talking to another TACAN unit, not a ground station. If you were in receive-only, you wouldn’t send the interrogation and thus couldn’t obtain range. If you were in transmit-only, you’d send interrogations but never receive the ground reply, so you wouldn’t get range either. The mode that provides both range and bearing to the ground station is transmit/receive.