What are 'navaids' used for in navigation?

Navaids, short for navigational aids, play a critical role in air navigation by providing pilots with necessary information to determine their position and navigate safely through the airspace. Examples of navaids include VORs (VHF Omnidirectional Radio Range) and NDBs (Non-Directional Beacons), which transmit radio signals that allow aircraft to ascertain their bearing and distance from the station. This information is essential for route planning and ensuring that pilots remain on intended flight paths, enhancing overall safety and efficiency in aviation.

In contrast, the other options do not accurately describe the function of navaids. Tools for aerodynamics analysis focus on aircraft performance and design, while emergency landings pertain to contingency procedures rather than navigational assistance. Lastly, although fuel calculations are important for flight planning and operations, they do not fall under the definition or usage of navigational aids.