During the Vietnam War, American commandos developed an insertion and extraction method for operations in the jungle that is still used by today’s special operators. The Special Patrol Insertion/Extraction (SPIE) system is designed for small special operations teams that operate in areas where an enemy presence or the terrain prevents helicopters from landing.

The SPIE technique hasn’t been used operationally for decades, in part because U.S. air superiority and lackluster enemy anti-aircraft capabilities have meant it wasn’t needed.

But as the U.S. military gears up for great-power competition against near-peer adversaries, like China and Russia, the SPIE technique becomes relevant again, especially in a potential conflict in the Pacific.

Warriors of the Jungle

SOG team STABO exfiltration
SOG recon team members dangling in mid-air after being evacuated from the jungle.  Courtesy photo

The SPIE system can be traced to the rope insertion and extraction techniques of the Vietnam War. It was the innocuous-sounding Military Assistance Command Vietnam-Studies and Observations Group (MACV-SOG) that invented and used the method.

A highly classified unit, SOG took the fight to the North Vietnamese Army and Vietcong, conducting cross-border operations into Laos, Cambodia, and North Vietnam — where U.S. troops officially shouldn’t have been.

Composed of Green Berets, Navy SEALs, Recon Marines, Air Commandos, and indigenous forces, SOG tried to stop the onslaught from the North and give South Vietnam some breathing space.

SOG’s classified operations mainly took place in rough and inaccessible jungle, where the NVA had built the infamous Ho Chi Minh trail complex, over which flowed supplies to its forces in South Vietnam. The terrain restricted operations and often forced SOG teams to create their own landing zones by either detonating explosives or by requesting B-52 bombing runs to create craters where helicopters could land.

But landing wasn’t always an option. Secrecy was paramount for mission success. After all, SOG patrols of six to 14 men didn’t have a chance of survival against hundreds or thousands of NVA in an open battle.