Which navigation concept uses onboard sensors and GPS for position rather than ground-based aids?

• A. RNAV using onboard sensors and GPS for position
• B. VOR navigation
• C. ADF navigation
• D. Dead reckoning with no sensors

Answer: (A)

This concept is Area Navigation (RNAV), where position is determined by onboard navigation sensors and GPS rather than external ground-based aids. With RNAV, the aircraft uses internal sensors—such as inertial systems—and satellite signals from GPS to figure out its exact position, so it can navigate along a path that isn’t constrained to conventional beacons. The GPS data provides precise, global positioning, allowing flexible routing and more efficient flight plans without needing to tune into VORs, NDBs, or other ground stations.

In contrast, VOR navigation relies on signals from ground-based VOR stations to establish a bearing to the station (and often DME for distance). ADF navigation uses ground-based non-directional beacons to determine a direction to the beacon. Dead reckoning with no sensors would depend only on speed, heading, and time from a last known position, offering little current accuracy without sensor input.