What are the two types of navigational aids typically used in instrument flying?

In instrument flying, the primary navigational aids are essential for ensuring that pilots can navigate safely and accurately when visibility is low or when flying through clouds. Ground-based navigational aids include systems such as VOR (VHF Omnidirectional Range) and NDB (Non-Directional Beacon), which operate from fixed locations on the ground and provide reference signals for pilots.

On the other hand, satellite-based systems, such as GPS (Global Positioning System), provide precise location data and are critical for modern navigation. These systems complement the ground-based aids by offering capabilities such as three-dimensional positioning, which enhances situational awareness and supports advanced navigation techniques.

Together, these two types of navigational aids form the backbone of instrument flying, allowing pilots to maintain course and altitude even in challenging conditions. This combination also reflects the evolution of navigational technology, where ground-based aids have been supplemented and in some cases enhanced by satellite systems, improving overall accuracy and reliability in navigation.