Private Pilot Private Practice Exam

The correct answer is that an aircraft must have a VHF transmitter and receiver to utilize VHF/DF (Very High Frequency/Direction Finding) facilities for assistance in locating its position. VHF/DF systems work by receiving radio signals transmitted by the aircraft. The VHF receiver picks up these signals, while the VHF transmitter is used to send a signal that can be triangulated by ground stations equipped with direction-finding capabilities. This enables the ground stations to determine the aircraft's position based on the direction of the received signals.

In the context of the other options, GPS and radar transponders, while useful for navigation and surveillance, are not directly related to the VHF/DF capabilities. HF radios and satellite communicators operate on different frequencies and technologies, which do not integrate with the VHF/DF systems specifically. Similarly, VOR (VHF Omni-directional Range) and NDB (Non-Directional Beacon) systems are navigation aids but do not involve the direction-finding techniques that are part of VHF/DF operations.

Thus, the requirement of a VHF transmitter and receiver is essential for taking advantage of VHF/DF facilities, making it the appropriate choice.