Light Observation Helicopter

Infobox Aviation
name= Light Observation Helicopter


caption= An OH-58 Kiowa, winner of the LOH competition's second round

The Light Observation Helicopter (LOH) program was a United States Army program to evaluate, develop and field a light scout helicopter. The program would yield two helicopters primarily used for "scout" observation missions.

Design selection

In 1960, the United States Army issued Technical Specification 153,cite book|last=Apostolo|first=Giorgio|title=The Illustrated Encyclopedia of Helicopters|year=1984|location=New York|publisher=Bonanza Books|id=ISBN 0517439352] a request for proposals (RFP), for a four-seat, turbine-powered, light observation helicopter capable of fulfilling various roles: personnel transport, escort and attack missions, casualty evacuation and observation. 12 manufacturers, including Hughes Tool Co. Aircraft Division, Hiller Aircraft and Bell Helicopters, entered the competition. [cite web|url=http://www.webcitation.org/5JRs1SFaO|title=The Cessna CH-1 Helicopter|author=Steve Remington|publisher=CollectAir|work=|date=] The United States Navy provided technical expertise to assist the Army in evaluating the design proposals.cite paper|title=George A. Spangenberg Oral History|author=George A. Spangenberg, edited by Judith Spangenberg-Currier|url=http://www.georgespangenberg.com/gasoralhistory.pdf|format=pdf pp.187-190|publisher=www.spangenberg.org ] In October 1961, the Army selected three of the designs for a flight evaluation. Bell's Model 206 design was recommended by the Army team and designated the YHO-4 (later YOH-4),cite web|url=http://www.webcitation.org/5J1lvgxQH|title=U.S Army Aircraft Acquisition Programs|work=Uncommon Aircraft 2006|author=Robert Beechy|date=18 November 2005] Hiller's Model 1100 was recommended by the Navy team and became the YHO-5 (later YOH-5), and Hughes' Model 369 was added to the competition and became the YHO-6 (later YOH-6). Each manufacturer submitted 5 test and evaluation prototypes of their designs to the Army for flight test evaluation at Camp Rucker, Alabama.

As a result of the flight evaluation, Hiller's YOH-5 and Hughes' YOH-6 were selected to compete in a program cost analysis bid for the contract. The Hughes bid won the contract, although Hiller protested the contract award, and in 1965, the YOH-6 was redesignated as the OH-6A Cayuse. In 1967, the Army reopened the LOH competition for bids and Bell resubmitted for the program using their model 206A design. Fairchild-Hiller failed to resubmit their bid with the YOH-5A, which they had successfully marketed as the FH-1100. [cite web|url=http://www.webcitation.org/5JNrx2yIy|title=US and Russian Helicopter Development In the 20th Century|author=Michael J. Hirschberg and David K. Daley|date=7 July 2000] In the end, Bell won the contract and the model 206A was designated as the OH-58A. Following the Army's naming convention for helicopters, the OH-58A was named Kiowa for the Native American tribe.

ee also

* Bell YOH-4
* Fairchild Hiller YOH-5
* OH-6 Cayuse
* OH-58 Kiowa

References