Why are TACAN antennas positioned at both the top and bottom on navy aircraft?

The positioning of TACAN (Tactical Air Navigation) antennas at both the top and bottom of Navy aircraft serves to provide navigation redundancy. This configuration ensures that the aircraft can receive signals from the TACAN system effectively regardless of its orientation or potential obstructions. By having antennas in multiple locations, the system can maintain accurate navigation data, increasing the likelihood of reliable signal reception in various flight conditions and scenarios. This redundancy is crucial for mission success, especially in tactical and combat environments where precise navigation is essential. Furthermore, if one antenna were to malfunction or become obstructed, the second antenna could continue to provide necessary navigation data, thereby enhancing the overall safety and operational reliability of the aircraft.