Vietnam Choppers (Revised Edition)

This extract is taken from the chapter entitled ‘Gunship Tactics.’

The need to deny the enemy freedom of movement during the hours of darkness led to the development of a variety of helicopter night sensors, which gave rise to a series of Huey ‘night fighters’. The most widespread was known as ‘Nighthawk’. The system compromised an AN/TVS-4 Night Observation Device (NOD) or ‘starlight scope’ mounted above an AN/VSS-3A Xenon searchlight with both infrared and white light capability, which equipped the M-551 Sheridan Airborne Armored Reconnaissance Vehicle. Together with an M-134 minigun, the system was fitted in a UH-1D/H which operated in conjunction with one or two gunships, flying between 500 and 1,000 feet AGL at about 50 knots with the gunships to the rear at about 1,500 feet. When the Nighthawk detected a target by means of the NOD and IR it could either illuminate the area with white light, open fire with the minigun, or both, with the accompanying gunships then firing into the minigun’s tracer pattern.

The Nighthawk proved very effective in areas of sparse vegetation and along canals and waterways, especially for the interdiction of sampan supply traffic. Nighthawks were also employed as a reaction force to exploit targets acquired by ground surveillance radar such as the AN/TPS-25 in what were known as ‘Night Hunter’ operations. The moving target radar operated from a secure area, usually a fire support base, and when a suitable target had been sighted and plotted the Nighthawk team was alerted. The aircraft then flew to the target area, which was illuminated by artillery at the moment Nighthawk arrived at the scene. Once the enemy were located and marked by the light ship, gunships engaged them with rockets and minigun fire.