These 'Loach' pilots were crazy mother fuckers, flying at tree top level to irritate and draw fire from the VC, then the Cobra's would roll in and neutralize the situation.
The Boeing (McDonnell Douglas, formerly Hughes) OH-6A was designed for use as a military scout during the Vietnam war to meet the U.S. Army's need for an extremely maneuverable light observation helicopter (under the 1963 LOH program). The Army initially ordered 1,438 Hughes Model 369s, designated by the Army as the OH-6A Cayuse helicopters, fielded in Vietnam in early 1968. The OH-6A was used for command and control, observation, target acquisition, and reconnaissance, organic to division, brigade, and battalion size units. The four-passenger teardrop shaped "Flying egg" (six-passenger with rear seats folded-down) was a small, light, sturdy, maneuverable helicopter, with very low drag.
The OH-6A Cayuse was quite effective when teamed with the AH-1G Cobra attack helicopter as part of what were known as "Pink Teams". The OH-6A "Loach" (for "LOH") would find targets by flying low, "trolling for fire", then marking the target with colored smoke to lead in a Cobra, or "Snake", to attack. The Cayuse could absorb an extensive amount of small arms fire and still bring the crew home safely. The OH-6A could be armed with the M27 armament subsystem, the port-side mounting M134 six-barrel 7.62mm "Minigun" or a 40mm grenade launcher on the XM8 armament subsystem. In addition, an M60D 7.62mm machine gun could be mounted in the rear starboard door opening.