According to T-54A operating procedures, how many different DMEs can a pilot display on their PFD?

The correct answer indicates that a pilot can display three different Distance Measuring Equipment (DME) readings on their Primary Flight Display (PFD). This capability is particularly significant for navigation, as multiple DMEs allow pilots to triangulate their position relative to various ground stations, enhancing situational awareness and navigation accuracy.

Having more than one DME displayed on the PFD helps pilots in complex airspace where several navigational aids may be present. It allows them to choose the most relevant DME reading based on their flight path or waypoint, facilitating better planning for upcoming navigation decisions as they fly. This feature supports efficient route management and aids in situations where diversions or alternate routes may be necessary.

The ability to select and display three DMEs ensures pilots have access to essential distance data without cluttering the PFD, maintaining clarity while providing critical information for safe operation.