What type of navigation system relies on VORs for guidance during IFR flights?

The correct answer is ground-based navigation. This category includes navigation systems that utilize a network of terrestrial signals to determine an aircraft's position and guide its flight path. VOR, or VHF Omnidirectional Radio Range, is a key component of ground-based navigation and is widely used in Instrument Flight Rules (IFR) operations.

VOR stations provide radio signals that pilots can receive, allowing them to determine their aircraft's bearing from the station. This is essential for maintaining course and situational awareness during IFR flights, where visibility may be limited. Ground-based navigation systems, like those relying on VORs, offer reliable guidance and are integral to the air traffic management infrastructure.

While radar navigation involves the use of radar technology to provide position information, it does not directly rely on VOR signals. Inertial navigation uses onboard sensors for positioning and does not depend on external ground sources. Satellite navigation relies on signals from satellites, such as GPS, rather than ground-based VOR stations. Therefore, ground-based navigation is the most accurate description of a system utilizing VORs for guidance during IFR flights.