An American MACV-SOG* reconnaissance group after being evacuated from the Vietnamese jungle by a CH-53 Sea Stallion helicopter via a STABO (STAbalized BOdy) system during Operation Tailwind in Laos in September 1970 during the Vietnam War. An AH-1 Cobra attack helicopter is shown providing escort.
Members of MACV-SOG carried out some of the most dangerous and top-secret missions of the Vietnam War.
The design for the STABO system was first created on a napkin by U.S. Special Forces Sergeant First Class Clifford Roberts after he saw a wounded man accidentally fall out of a McGuire extraction rig in a combat evacuation. With the aid of two others named Major Robert Stevens and Captain John D. H. Knabb, Sergeant Roberts made a prototype of his STABO design out of parachute lofts on the sewing machines his unit used to repair parachutes. When he presented the design to his superiors, they approved it and ordered 500 rigs. Roberts was subsequently awarded the Bronze Star for the successful design.
STABO was later used to evacuate soldiers from areas where helicopters cannot land, such as in the thick jungle canopies of Southeast Asia. The evacuees would fly like this for a short while until the evacuation helicopter could find a spot to land and load them inside. STABO was later replaced by the SPIE (Special Patrol Insertion/Extraction) system, which itself is a direct and very similar descendant of the STABO rig.

*MACV-SOG—Military Assistance Command, Vietnam—Special Operations Group (later renamed Studies and Observations Group), was the elite military unit of the Vietnam War, so secret that its existence was denied by the U.S. government. The group reported directly to the Pentagon’s Joint Chiefs of Staff, and much of its history and exploits were concealed for years from the general public by a veil of secrecy and confidentiality.