Where should DME antennas be located on an aircraft?

The correct choice indicates that DME antennas should be located on the lower surface of the aircraft and not blanketed by the wings. This positioning is critical for the effective operation of Distance Measuring Equipment (DME), which relies on line-of-sight communication with ground stations. When placed on the lower surface, the antenna has a clear path to transmit and receive signals, minimizing obstructions that could lead to signal degradation or loss.

Mounting the antennas where they will not be blanketed by the wings is particularly important, as the wings can obstruct the RF signal path, leading to inaccuracies in distance measurement and potentially affecting navigation. Proper installation ensures optimal performance, contributing to the reliability and accuracy of aircraft navigation systems.

The other options present locations that would compromise the DME's functionality. For example, placing the antennas on the upper surface might expose them to physical damage and interference from other aircraft components, while positioning them inside the cabin would severely inhibit their signal transmission and reception capabilities, leading to operational issues. Similarly, attaching them to the tail section could also introduce obstructions and impair the ability to reliably communicate with ground stations.