Lockheed Missiles YO-3A "Quiet Star"

Lockheed Missiles YO-3A "Quiet Star" Restored instrument panel of pilot's cockpit  in the aircraft at the  Western Museum of Flight.

During the Vietnam war, the U.S. Military felt an urgent need for a low-flying, quiet aircraft with sensors mounted aboard in order to track enemy movement throughout dense jungle areas.

Lockheed Missiles and Space Company engineers visualized the use of a Schweizer SGS 2-32 sailplane coupled with a muffler-equipped engine driving a slow-turning propeller in order to fill that need.

After successful experimentation with earlier versions of quiet aircraft known as QT-1 and QT-2,
Lockheed pressed on with the final variant known as the YO-3A; a two-place version with the observer in the front seat and pilot in the rear.

In July 1968, an order for 14 YO-3A’s was placed by the U.S. Army Aviation Systems Command.  Serial numbers ran consecutively from 69-18000 thru 69-18013.  Thirteen of these aircraft were shipped to Vietnam while aircraft number 69-18000 remained in the U.S. for further testing by the Army.

Since all YO-3A missions were nighttime operations, the aircraft were equipped with infra-red detection systems which enhanced the observers ability to locate enemy troop movements.  The aircraft were so quiet the enemy never suspected they were flying just a few hundred feet over their heads.  Once targets were spotted, air strikes would be called up to deliver their munitions on the designated targets.

YO-3A’s were equipped with 210 hp Continental IO-360D six-cylinder air-cooled engines.  A six-blade fixed-pitch propeller was initially installed on the aircraft but was later replaced by a three-blade variable pitch propeller.

The example at our museum is serial 69-18007.  This particular aircraft saw service in Vietnam at both Long Than North Air Base and Phu Bai Air Base as part of the 73rd Aviation Company and the 220th Aviation Company.  Crew members  affectionately referred to it as "Double-Oh-Seven."

The aircraft returned to the U.S. in 1972 and served briefly with the Louisiana Department of Wildlife and Fisheries.  It was then shipped to Pt. Mugu Naval Weapons Center for storage and subsequent acquisition by our museum.