Final answer:
Merging target procedures are used by ATC for all types of aircraft—helicopters, fighter jets, and commercial airliners—to ensure safe separation when radar indicates converging paths.
Step-by-step explanation:
Merging target procedures apply to all aircraft that fall under air traffic control (ATC). These procedures are necessary when two or more aircraft appear to converge on radar, making it vital for the air traffic controllers to ensure safe separation between them. The merging target procedures involve providing pilots with traffic advisories, assuring that pilots have identified the converging traffic, or if needed, offering avoidance instructions to maintain safety. This applies to helicopters, fighter jets, and commercial airliners—in fact, any aircraft that is under the guidance of ATC could be subject to these procedures.