What does the suffix 'P' indicate about the aircraft's transponder?

The suffix 'P' associated with an aircraft's transponder indicates that the aircraft is equipped with a transponder that has Mode C capability along with TACAN (Tactical Air Navigation) capability. This means that the transponder can provide altitude information (a key feature of Mode C) and is capable of interfacing with the TACAN system, which is used primarily by military aircraft for navigation and positioning.

Mode C transponders are required for certain types of airspace as they enhance situational awareness for air traffic control by relaying both the aircraft's identity and its altitude. The additional TACAN capability allows the aircraft to receive precise navigation assistance, particularly useful in military operations or in areas where TACAN facilities are in use.

The other options do not accurately represent the meaning of the suffix 'P' regarding transponder capabilities and, therefore, do not align with the correct definition. Understanding the use of transponder suffixes is essential in air traffic management and ensures proper communication and navigation among aircraft.