The Hughes Helicopters OH-6 Cayuse (nicknamed Loach) is a single-engine light helicopter with a four-bladed main rotor used for personnel transport, escort and attack missions, and observation. Hughes also developed the Model 369 as a civilian helicopter, the Hughes Model 500, currently produced by MD Helicopters.
The first Model 369 prototype flew on February 27, 1963. Originally designated as the YHO-6A according to the Army's designation system, the aircraft was redesignated as the YOH-6A in 1962 when the Department of Defense created a Joint designation system for all aircraft. Five prototypes were built, fitted with a 252 shp Allison T63-A-5A, and delivered to the U.S. Army at Fort Rucker, Alabama to compete against the other 10 prototype aircraft submitted by Bell and Fairchild-Hiller. During the course of the competition, the Bell submission, the YOH-4, was eliminated as being underpowered (it used the 250shp T63-A-5). The bidding for the LOH contract came down to Fairchild-Hiller and Hughes. Hughes won the bid, and the Army awarded a contract for production in May 1965, with an initial order for 714 which was later increased to 1300 with an option on another 114. Production reached 70 helicopters in the first month.
Shortly after production began, the OH-6 began to demonstrate what kind of an impact it would have on the world of helicopters. The OH-6 set 23 world records for helicopters in 1966 for speed, endurance and time to climb. On March 23, 1966, Jack Schwiebold set the closed circuit distance record in a YOH-6A at Edwards Air Force Base, California. He flew without landing for 1,739.96 mi (2,800.20 km). And on April 7, 1966, Robert Ferry set the long distance world record for helicopters. He flew from Culver City, California to Ormond Beach, Florida, covering a total of 1,923.08 nm (2,213.04 mi, 3,561.55 km).
Production OH-6A craft entered service in 1966, arriving in the Vietnam War thereafter. The pilots dubbed the little helicopter Loach, a word created by pronunciation of the acronym of the program that spawned the aircraft, LOH (light observation helicopter). The helicopter quickly became noted for high performance and low noise due its four-bladed rotor and small size. The OH-6A would act as a scout to spot enemy positions, while only lightly armed with a fixed minigun. The most common configuration had an observer/gunner either in the left seat or in the rear seat. Most commonly, the Loach worked in conjunction with another OH-6 or an AH-1 Cobra gunship. A pair of OH-6s was sometimes known as a "white team", while an element of AH-1 Cobras was referred to as a "red team". An OH-6 and an AH-1 operating together comprised a "Pink team".
Following the April 1980 failure of Operation Eagle Claw, it was determined that the military lacked aircraft and crews who were trained and prepared to perform special operations missions. To remedy this shortcoming, the Army began developing a special aviation task force to prepare for the next attempt to rescue the hostages; Operation Honey Badger.
The pilots selected to fly the OH-6A helicopters came from the 229th Attack Helicopter Battalion and were sent to the Mississippi Army National Guard's Army Aviation Support Facility (AASF) at Gulfport, Mississippi, for two weeks of qualification training in the aircraft. When the training was completed, C-141 aircraft transported the aircraft and crews to Fort Huachuca, Arizona, for two weeks of mission training. The mission training consisted of loading onto C-130 transport aircraft which would then transport them to forward staging areas over routes as long as 1000 nautical miles. The armed OH-6 aircraft from Fort Rucker joined the training program in the fall of 1980.
Operation Honey Badger was canceled after the hostages were released on 20 January 1981, and for a short while, it looked as if the task force would be disbanded and the personnel returned to their former units. But the Army decided that it would be more prudent to keep the unit in order to be prepared for future contingencies. The task force, which had been designated as Task Force 158, was soon formed into the 160th Aviation Battalion. The OH-6A helicopters used for transporting personnel became the MH-6 aircraft of the Light Assault Company and the armed OH-6As became the AH-6 aircraft of the Light Attack Company.
For other AH-6 and MH-6 variants, see MH-6 Little Bird.