Final answer:
The statement that the RADIO NAV page displays navaids tuned by the FMGS or flight crew is true. This page shows vital navaid information that aids in navigation during flight.
Step-by-step explanation:
The question regarding whether the RADIO NAV page displays navaids tuned by the FMGS (Flight Management and Guidance System) or flight crew is indeed a true statement. In the context of aviation, the RADIO NAV page is a component of the aircraft's Navigation Display or Multifunction Display that allows pilots to view and interact with radio navigation aids. The FMGS is responsible for managing inputs from the flight crew and automatically tuning navaids based on the flight plan.
Pilots can manually input frequencies for specific navaids they wish to tune, or the system can be set to auto-tune these aids, based on the active flight plan. This information is then reflected on the RADIO NAV page, presenting the crew with crucial information such as the selected navaid's identifier, frequency, and distance, helpful during different phases of a flight.