Intended for use in the suppression of enemy air defenses role, the rocket reached the flight-testing stage before being cancelled.

A requirement for a new type of unguided rocket, to be used to suppress enemy anti-aircraft artillery batteries, was identified by the United States Navy in 1966.

[1] Six inches (152 mm) in diameter,[3] HART would be powered by a solid-fueled rocket, and would use flechette anti-personnel warheads to provide the greatest possible effect against the intended targets.

[1] In 1967, a contract for the development of HART was given to the Martin Marietta corporation, based in Orlando, Florida; the rocket received the official designation of AGR-14 ZAP, for "Zero Anti-Aircraft Potential",[3] at this time.

[1] Despite the rocket being tested successfully, the project was cancelled shortly thereafter, and ZAP failed to reach operational service.