Battle of Lima Site 85

Phou Pha Thi is a remote mountain in Houaphanh Province, northeastern Laos. The mountain, which is about high, is located within the former Royal Lao Army's Military Region 2, and about from the border of the Democratic Republic of Vietnam and away from Sam Neua, the Pathet Lao capital. For the local Hmong and Yao tribes that lived in the area, Phou Pha Thi was a place of religious significance. They believed it was inhabited by spirits possessing supernatural powers to exercise control over their lives. The United States Air Force (USAF) saw Phou Pha Thi as an ideal location for installing a radar navigation system to assist pilots in their bombing campaigns in North Vietnam, and along the Ho Chi Minh Trail inside Laos. Laos was a neutral country according to the International Agreement on the Neutrality of Laos signed on 23 July 1962. Therefore, the United States was prohibited from openly conducting military operations in the kingdom. Activities undertaken by the USAF in Laos had to be approved by the ambassador to Laos, William H. Sullivan. When the plan to install a navigation system on Phou Pha Thi Mountain was proposed, Sullivan initially opposed it as he thought that Laotian Prime Minister Prince Souvanna Phouma would not allow his country to be involved in an aerial offensive against North Vietnam. Souvanna Phouma did permit the installation, on the condition that it not be manned by U.S. military personnel. , the site of a U.S. TACAN facility known as Lima Site 85. In August 1966, the USAF installed a TACAN System, an autonomous radio transmitter that provided pilots and navigators with distance and bearing relative to the station on Phou Pha Thi. In 1967, under the code name Heavy Green, the facility was upgraded with the TSQ-81, which could direct and control attacking jet fighters and bombers to their targets and provide them with precise bomb release points. It began operating in late November 1967 as Operation Commando Club. To operate the equipment within the limitations imposed by the Laotian Prime Minister, USAF personnel assigned to work at the installation had to sign paperwork that temporarily released them from military service, and to work in the guise of civilian technicians from Lockheed Personnel working at the TACAN site were supplied by weekly flights of the 20th Special Operations Squadron, based at Udorn RTAFB in northeastern Thailand operating under the code name Operation Pony Express, using Lima Site 85, the airstrip constructed by the Central Intelligence Agency in the valley below. Hmong General Vang Pao, who spearheaded the allied war effort against North Vietnamese and Pathet Lao forces in Military Region 2, was entrusted with the task of guarding the facility using the Hmong Clandestine Army alongside CIA-funded Thai Border Patrol Police forces. ==Prelude==

As USAF ground controllers were able to guide attacking aircraft against North Vietnamese targets in all types of weather, installation of the TSQ-81 radar system on Phou Pha Thi was considered to have been extremely successful during the final months of 1967. Yet a formerly top-secret after-action report credited Commando Club with guiding the following sorties: Secord said that, given the site's meager defenses, he felt the site could not be held against a serious assault. Secord's fears were justified, as USAF reconnaissance aircraft regularly flying over northeastern Laos in 1967 revealed that the paved roads constructed by the North Vietnamese were obviously approaching Phou Pha Thi. Road construction activities were observed along Routes 6 and 19, which connected Dien Bien Phu in North Vietnam with Phou Pha Thi and Nam Bac in Laos. On 16 December, two Pathet Lao companies overran Phou Den Din, only east of Lima Site 85. Shortly afterwards, Hmong units recaptured the village. In the first week of 1968, the combined PAVN and Pathet Lao forces probed Royal Laos Army positions in the area by launching several artillery attacks. On 10 January, a Pathet Lao patrol was driven from the area by the Hmong soldiers. Fearing the explosives attached to their equipment could be detonated by incoming artillery rounds, US technicians dismantled the charges and threw them over the cliff. As they repeatedly attacked the facility, ground fire heavily damaged one AN-2, and it crashed into a mountainside. By now, CIA officers and US controllers at Lima Site 85 had managed to contact an Air America helicopter, which was faster than the Soviet-made biplanes. The Huey pilot Captain Ted Moore sighted the remaining An-2, and promptly gave chase. As he pulled alongside, flight mechanic Glenn Woods armed with an AK-47 assault rifle opened fire and caused the biplane to crash into a ridge. The remaining An-2s had observed the attack from a distance and managed to escape without damage. Four Hmongs, two men and two women, had been killed by the North's attack. The TSQ-81 radar and associated equipment were undamaged. Despite the attack, the US Embassy in Vientiane and the USAF refused to alter their strategy for defending Lima Site 85. Lieutenant Colonel Clarence F. Blanton, commander of USAF personnel at the facility, was given no authority to supervise his own perimeter or to order a retreat if they again came under attack. Throughout January and February, intelligence collected by the Hmongs confirmed that a major assault on Lima Site 85 was being prepared, but Sullivan and the US military took no steps to strengthen the defenses. In late February, a Combat Controller, Technical Sergeant James Gary, arrived to augment the defenses by directing air strikes. He was replaced in this duty by Sergeant Roger D. Huffman on about 4 March. ==Battle==

North Vietnamese plan and preparations On 18 February 1968, a PAVN artillery survey team was ambushed near Lima Site 85 by Hmong reconnaissance teams, killing a PAVN officer in the process. The dead officer, who was a major, carried a notebook which revealed a plan to attack Phou Pha Thi by using three PAVN battalions and one Pathet Lao battalion. Prior to the mission, Muc's soldiers had undergone nine months of special training, mainly focused on mountain fighting techniques and jungle operations. They also conducted physical conditioning, to improve their physical fitness and stamina to undertake operations in the most extreme conditions in Laotian territory. On 18 December 1967, following their intensive training, soldiers of the PAVN 41st Special Forces Battalion launched the first phase of their operation by conducting terrain reconnaissance and watching activities on Lima Site 85 to learn their opponent's routines. As part of the second phase, commenced on 22 January 1968, six PAVN sappers were sent out to climb Phou Pha Thi, to pinpoint opposing positions in and around Lima Site 85, as well as routes of withdrawal. To maintain secrecy and surprise, Muc was ordered to avoid contact with local civilians and opposing military forces. In the event they were engaged by opposing forces, the PAVN would deploy a small force to deal with the situation while the main formation would continue moving to their objective on Phou Pha Thi. Once the PAVN formation had arrived at their assembly area, they were to be divided into two assault groups. The first assault group, under Muc's direct command, was divided into five "cells" to attack key targets at Lima Site 85. Cells 1 and 2 were given the mission of capturing the communications center, with the latter given the secondary role of supporting Cell 3, which was given the main mission of seizing the TACAN site and eliminating all US personnel. Cell 4 was to capture the airstrip, and Cell 5 was placed in reserve. Second Lieutenant Nguyen Viet Hung was given responsibility to lead the second assault group with the mission of neutralizing the Thai positions. The attack would commence during the early hours of 9 or 10 March. To capture Lima Site 85, the PAVN Special Forces were equipped with three Chinese-made K-54 pistols, 23 AK-47 assault rifles, four 7.62mm carbines and three RPG-7 rocket propelled grenade launchers. Under the cover of the artillery bombardment, the PAVN Special Forces sent a small team up the mountain to defuse mines and quick-fuse grenades, and to establish their routes of infiltration. At 21:15 Sullivan considered evacuating all US personnel from the facility at first light. However, officers of the Seventh Air Force contacted the US Embassy in Laos and indicated that evacuation should only occur as the last resort, when the situation on top of Phou Pha Thi was no longer under their control. "control and plotting" and radar vans. "TACAN" is the box shelter for the AN/TRN-17 electronics with antenna on top, and "LZ" is for the nearby helicopter Landing Zone. Also not shown are the CIA airstrip and command post. At 21:21 the PAVN resumed their artillery attack on Phou Pha Thi, followed by several infantry assaults by the PAVN 766th Regiment, which prompted Sullivan to order the evacuation of six technicians by 08:15 the next morning, from a contingent of 19 US personnel. About 03:00 Cell 1 moved to within of their objective, with Cell 5 positioned behind them. At the same time, the commander of Cell 4 decided to maneuver his unit to the west side of the airstrip instead of the east side as originally planned, because the terrain on the east side was higher and was covered by buildings. Precisely at 03:45, Cell 1 moved to within of the communications center, when they bumped into a Hmong outpost. Both sides exchanged fire, and the outpost was destroyed by a grenade while the Hmong soldier guarding the post retreated. Shortly after, a soldier from Cell 1 fired an RPG-7 grenade which destroyed the TACAN antenna. Within 15 minutes, Cells 1 and 2 had secured the communications site. Signaled by the explosion of Cell 1's RPG-7 round, Cell 3 immediately attacked the TACAN installation by firing one of their own RPG-7s, which destroyed the electric generators. Raven Forward Air Controllers at Lima Site 20A, being the nearest available American support, were awakened by a radio call about 04:00. They flew in the dark to Lima Strip 36 at Na Khang to position themselves at the airstrip closest to Lima Site 85. The Ravens took up station over Lima Site 85 at dawn. At 05:15 Sullivan, from the US Embassy in Vientiane, decided to evacuate Lima Site 85. He gave a signal to US pilots at Udorn to begin the operation, which was due to start at 07:15. Sullivan did not realize that US technicians were no longer in control of their TSQ-81 equipment. In response, the PAVN Special Forces organized a defense around the TACAN site, and hid their dead and wounded comrades under the large rocks which dotted Phou Pha Thi. By midday, Lima Site 85 was fully controlled by the PAVN 41st Special Forces Battalion, and they held the facility until 14 March when they withdrew from the area. ==Aftermath==

Just before midday on 11 March, the USAF turned their attention from looking for their missing personnel to that of destroying the captured radar, along with all the documentation and operation information left behind at Lima Site 85. Between 12–18 March, the USAF conducted a total of 95 strike sorties against the radar site, and on 19 March an A-1 fighter-bomber destroyed every building at the facility. In addition to the destruction of their radar equipment, the USAF bombing of Lima Site 85 may also have had the effect of obliterating the bodies of US personnel left behind at the site (two sets of remains were found in 2013). In the days following the loss of Phou Pha Thi, Sullivan reflected on the disaster at Lima Site 85 and commented that US technicians operating there should have been evacuated on 10 March, when it became amply clear the PAVN were preparing to launch an assault. A total of 12 US personnel went missing or were killed in the fighting on Phou Pha Thi; 11 were killed or missing on the ground and one was shot dead during the evacuation. A USAF A-1 searching for survivors was shot down and the pilot killed. The total casualty figures for PAVN, Pathet Lao, Hmong, and Thai units are unknown. According to official Vietnamese history, the PAVN 41st Special Forces Battalion suffered one soldier killed and two wounded in their fight for Lima Site 85. Against those losses, the Vietnamese claimed a total of 42 Hmong and Thai soldiers were killed, and a number of others were wounded. A large number of weapons were captured by the PAVN, including one 105 mm howitzer, one 85 mm artillery piece, four recoilless rifles, four heavy mortars, nine heavy machine guns, and vast amounts of ammunition. The PAVN victory proved to be a significant one, as they had succeeded in knocking out a major asset of the USAF, which had inflicted heavy damage to North Vietnam's limited industrial infrastructure. The fight at Phou Pha Thi, which was part of a larger military campaign waged by the North Vietnamese and their Pathet Lao allies, marked the beginning of the Communist dry-season offensive against Laotian Government forces in northeastern Laos. By September 1968, the strength of PAVN and Pathet Lao forces in the Sam Neua area were estimated to have numbered more than 20 battalions. Although airpower was to be a major factor in the defense of Lima Site 85, it could not be applied without limitations and restrictions. The defense of Lima Site 85 was not the sole focus of limited air resources at the time. During this period, the 1968 Tet Offensive was underway in South Vietnam, the Marine outpost at Khe Sanh Combat Base was under siege, and there existed an unprecedented flow of enemy logistical traffic which had to be interdicted. Lima Site 85 had provided direction to about a quarter of the USAF missions over North Vietnam and Barrel Roll from November 1967 to 11 March 1968. No other facility existed to provide a similar coverage over these areas. While this loss was a serious blow to the USAF effort, it was not crippling. Between 1994 and 2004, 11 investigations were conducted by both Joint POW/MIA Accounting Command (JPAC) and unilaterally by Lao and Vietnamese investigators on both sides of the border. In 2002 two of the former PAVN soldiers who had taken part in the attack told investigators that they threw the bodies of the Americans off the mountain after the attack as they were unable to bury them on the rocky surface. In March 2003, JPAC investigators threw dummies over the edge at those points indicated by the PAVN soldiers while a photographer in a helicopter videotaped their fall. That pointed the investigators to a ledge, below. Several mountaineer-qualified JPAC specialists scaled down the cliffs to the ledge where they recovered leather boots in four different sizes, five survival vests, and other fragments of material that indicated the presence of at least four Americans. On 7 December 2005 the Defense Prisoner of War/Missing Personnel Office (DPMAO) announced that the remains of Technical Sergeant Patrick L. Shannon had been identified and were being returned to his family. In September 2012 the remains of Colonel Clarence Blanton were identified. On 21 June 2024 the remains of Sgt. David S. Price were identified. On 23 June 2025 Staff Sergeant Henry G. Gish and Technical Sergeant Willis R. Hall were accounted for. On 23 June 2025 Tech. Sgt. Donald Kennebunk Springsteadah was accounted for. On 8 August 2025 Master/Sergeant James H. Calfee was accounted for. As of 1 January 2026 four of the airmen killed are still MIA/BNR: • S/Sgt. James Woodrow Davis • T/Sgt. Melvin Arnold Holland • S/Sgt. Herbert Arthur Kirk • S/Sgt. Don Franklin Worley On 21 September 2010, Chief Master Sergeant Richard Etchberger's Air Force Cross (awarded posthumously in 1968) was upgraded to the Medal of Honor by President Barack Obama at a White House ceremony for his actions during the Battle of Lima Site 85. A memorial to the USAF airmen killed and missing at Lima Site 85 and other Combat SkySpot airmen is co-located on Andersen Air Force Base, Guam, with the memorial to Operation Arc Light airmen. Another Combat SkySpot memorial is located at the Gunter AFB Enlisted Heritage Memorial Park. ==See also==

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