Which equipment suffix is used for an aircraft with DME and no transponder?

The suffix used to identify an aircraft equipped with Distance Measuring Equipment (DME) but lacking a transponder is the character /D. In aviation, equipment suffixes serve to inform air traffic controllers and other aviation personnel about the capabilities of an aircraft's navigation and communication systems.

The /D suffix specifically indicates that the aircraft has DME, which allows it to measure distance from ground-based navigation aids, essential for certain types of navigation. However, since the aircraft does not possess a transponder, which is used for radar identification and provides altitude information, the /D designation reflects the aircraft's limited capabilities in that respect.

Understanding this context is crucial for air traffic controllers as it influences how they manage traffic and provide separation based on an aircraft's navigational capabilities.