53 years later: SA reflects on Vietnam War Published March 29, 2023 By Robert Vanderpool OSI Command Historian QUANTICO, Va. -- On March 29th, the United States honors the bravery and sacrifice of its Vietnam War veterans with National Vietnam War Veterans Day. For Bill Arnold, a retired OSI Special Agent, it's a day to reflect on his service and his unique experience as a counterintelligence officer at Pleiku Air Base, Vietnam. Arnold joined the Office of Special Investigations in 1967, graduating from the OSI Academy Basic Course as a member of Class 67-H. He arrived in Vietnam as a first lieutenant in Jan. 1970. There, he was assigned to Detachment 5008 at Pleiku Air Base serving as a Counterintelligence and Area Source Program Officer. Prior to arriving in-country, Arnold completed a year of Vietnamese language training in California. “I was in [the Reserve Officers Training Corps] in college, my dad was an Air Force officer, and I knew I wanted a career in Air Force,” Arnold said, during a recent interview. “I was anxious to get to Vietnam. I went down and talked to the assignments people and said, you know, I want to get to Vietnam as quickly as possible. They said were not sending any second lieutenants to Vietnam, but they asked me what my Defense Language Aptitude Test Score was. I told them my score and they said that I would qualify for Vietnamese Language School. That was the surest way they knew for me to get to Vietnam quickly. So, I volunteered.” Ironically for Arnold, the additional year he spent attending language school put him behind many of his OSI Academy classmates when it came to getting to Vietnam. “By the time I got to Vietnam, a lot of the guys that were in my same year group, had already been there for about six months,” he said. “So, it backfired a little bit in that regard. But language training was good.” Arnold arrived at Pleiku on Jan. 3, but his initial time there was very short. After only about a week on station, he was temporarily transferred 60 miles west to Phu Cat Air Base, located near the city of Qui Nhon on the Vietnamese coast. The sudden transfer came about after the OSI detachment commander at Phu Cat got dysentery severe enough to require a medical evacuation flight back to the United States. With less than three years’ experience as a Special Agent, Arnold suddenly found himself as an interim detachment commander. “The district sent me to Phu Cat which was a very interesting assignment because it was a major fighter air base unlike Pleiku,” Arnold recalled. “It was a major target for the North Vietnamese and the Viet Cong. I don’t recall any really meaningful investigations during the few weeks I was at Phu Cat. The primary investigations of criminal nature in Vietnam were black marketing and drugs and thefts of government property. I suspect we had a little of each of those, but I can't remember any major cases that caught my attention. So, after about a month, probably about three weeks, I went back to Pleiku.” Pleiku Air Base was in the Vietnamese highlands, approximately 140 miles southwest of Da Nang and 240 miles northeast of the Vietnamese capital city of Saigon. The Air Force began operations at Pleiku in 1962, operating at first from a dirt airstrip there. By the time Arnold arrived at Pleiku in 1970, the base had grown into a major air base with modern facilities that housed several different flying units as a joint-use installation with the Vietnamese air force. Arnold’s primary mission as the counterintelligence officer at Pleiku was air base defense. Supported by local Vietnamese nationals, including a highly productive Montagnard (local indigenous person), Arnold was responsible for developing and managing counterintelligence source networks which would collect information about threats to the air base. The main responsibility of the Vietnamese nationals, whose official job title while working for OSI was interpreter translator, was to travel outside the base perimeter and establish contacts with the local people who lived in the vicinity of the air base to learn about potential threats. The Vietnamese nationals would then deliver what they learned back to Arnold, who in turn would prepare a written report that was forwarded to higher headquarters for further analysis. Reports would also be shared directly with the base Security Police forces and the base commander. “We were responsible for making sure that we were collecting information on enemy forces within an area around the perimeter that was susceptible to attack,” Arnold said. “We were primarily focused on the threat to the air base by active units from the Viet Cong, or sappers and others from North Vietnamese Army units. You had to be within 15 kilometers of the base to be able to get a rocket to go that far to hit the place. That established an expanded perimeter area for where we wanted sources to be active. “The way things were set up we were pretty limited in our ability to actually go out and recruit sources ourselves,” he continued. “We stood out pretty significantly and I was a little concerned about looking too much like intelligence because when you look like intelligence then you get targeted, and you can compromise your sources. The interpreter translators would collect information on suspected units of those nature in that radius around the air base. They could operate pretty freely in the area.” A major part of Arnold’s job was to evaluate the worthiness and truthfulness of the sources and the value of the information they were reporting. “One of my primary jobs was to evaluate the quality and reliability of the sources,” he said. “The sources were all being paid. They were a good set of eyes, but sometimes, if they felt they could get away with it, they would just make up information so they could get paid. Over the course of a month or two you could really zero in on which sources were your best resources.” In addition to managing the Vietnamese nationals, Arnold also developed significant relationships with his intelligence counterparts in various Army units operating in the vicinity of Pleiku. This effort further expanded OSI’s ability to collect counterintelligence information. “We had a Special Forces camp right outside the main gate of Pleiku,” Arnold said. “Any information I thought was something they could use I shared with them. I developed a liaison with their intelligence officer. If they had an operation going on anywhere in the area of a report, they would check it out. If there was a unit there that they came in contact with, or even if they didn’t make contact, they would say, hey, we were out there, here is what we saw or what we didn’t see. That was all useful information in terms of evaluating the sources that we had.” Arnold also established relationships with an Army helicopter unit located on the opposite side of Pleiku City. The helicopter unit agreed to conduct flights searching for indications of enemy forces in the area as identified by information delivered by the OSI established area source networks. Arnold was invited to ride along on one such occasion so he could observe and evaluate a report personally. “I jumped into one of the seats behind the pilot and strapped myself in for the flight,” Arnold said. “The pilot turned around, looked at me for a while and then said: ‘Who the hell are you and are you sure you want to go on this flight?’ I was confused because I knew my participation had been cleared by the intelligence officer. I probably stammered a reply, but the pilot just turned around and continued his preparation for the flight. Still confused over his remarks, it dawned on me that I was dressed in my one of my usual ‘uniforms of the day,’ civilian clothes. Remember this was 1970. My choice of civilian entire that day was a bright yellow shirt and green and yellow checked pants. The doors on each side of the rear of the Huey had to stay open as .50 caliber operators were located in each of the open doors. My yellow shirt made me quite a target for ground fire sitting in the open bay.” Though Arnold’s helicopter flight did not encounter any hostile fire that day, he was no stranger to being under enemy attack. During Arnold’s year at Pleiku, there were multiple incidents of both rocket and mortar attacks conducted by enemy forces against the base. “There were 13 attacks during the 12 months I was there,” Arnold said. “Most of them were rocket attacks against the air base. You’d hear the whistle. For most people it would wake you right up when you heard that whistle. You would immediately roll out of bed and under the bed. The bed was a metal framed flat spring bed. There was about a 2-inch mattress. Between the mattress and the springs was a half inch piece of plywood. That became the last protection from an attack. You would have a little bit of a bomb shelter there to protect you. The rocket attacks were interesting because you never knew exactly when the attack was over. Mortar attacks were different. They were a lot closer, and they had enough mortars that they would just walk a straight line across the base. They did a lot more damage.” Despite these attacks, OSI’s counterintelligence efforts to protect the base during Arnold’s tenure there paid off as there were no reported incidents of any friendly personnel being wounded or killed by enemy fire. The worst attack, which was a North Vietnamese Army rocket attack on May 7, 1970, resulted in the destruction of one aircraft and damaging two others. Another aspect of Arnold’s deployment, which he described as being something people today likely can’t even imagine happened, involved communication with loved ones back in the United States. In an era decades before the advent of the internet, email and text messaging, the primary method for conversation between deployed personnel and their family members other than the U.S. Mail was the Military Affiliated Radio System, or MARS. “To make a MARS call you had to stand in line,” he said. “Sometimes you had to stand in line for an hour or more to get a line. Once you got the line, you had to tell the radio operator who you wanted to talk to and where that person was located. The radio operator would then find an amateur radio operator in the United States in their vicinity. The radio operator would ask if they were willing to make a telephone call to what was hopefully for them a local number. The way it worked was that we would talk through this series of people. You had to say ‘over’ each time you talked back and forth. It worked out and it at least gave us an opportunity to talk in real time.” Arnold departed Vietnam in Dec. 1970. Over the next three years he was assigned to duty stations in Florida, Alabama and Arizona. In 1974, he attended a Korean Language and Cultural Studies program before returning overseas for a two-year assignment in Seoul, South Korea. Following subsequent stints in California, where he served as a detachment commander, and in Washington, D.C., where he served as a branch chief, Arnold served in Japan as a detachment commander from 1984 to 1987. He then returned to Korea from 1987 to 1990 as a deputy district commander and then a district commander. His last assignment with OSI was as the Counterintelligence Support Officer at the U.S. European Command Intelligence Directorate in Stuttgart, Germany, where served in a variety of senior leadership positions on the joint staff. Arnold retired from OSI in 1994 as a colonel, completing more than 27 years of active-duty service. This year also marks a significant anniversary in OSI’s history as it marks 50 years since OSI inactivated District 50 in Vietnam on March 27, 1973. District 50 was first activated on March 1, 1962, with headquarters at Tan Son Nhut Air Base near Saigon. District 50’s area of responsibility included the entire country of Vietnam and numerous detachments and operating locations were activated and inactivated in support of district operations throughout its 11 year history. Though OSI personnel served in Vietnam both before and after District 50’s operational period, the inactivation of the district largely symbolized the completion of OSI’s direct war time mission in country. In recognition of the 50th anniversary of District 50’s closing, Arnold, along with fellow retired Special Agent Bob Thompson, have been working on compiling a single volume history of OSI operations in Vietnam. Thompson, who retired from the Air Force Reserve in 1997 as a lieutenant colonel, served as the commander of Detachment 5008 at Pleiku Air Base between September 1971 and April 1972. Arnold and Thompson’s combined effort is expected to be completed later this summer. “The main thing is to recognize the people and the job that they did in Vietnam,” Arnold said. “We did some really great things in Vietnam. We had a bunch of great people that should be further recognized from a historical standpoint for the work they did. It’s going to focus on how things got started, the setup, the missions, and the people. We hope to identify everybody who had ever served in Vietnam during that period, at least recognize them by name. We are going to have stories that I'm sure everybody will enjoy reading.” National Vietnam War Veterans Day was first observed in 2012 following a Presidential proclamation for a planned 13-year program of commemorations marking the 50th anniversary of the end of the Vietnam War. March 29th was chosen as the annual observance date because it was on March 29, 1973, after more than 11 years of combat operations, that the last American combat troops officially departed Vietnam. Overall, the last American military personnel would not depart Vietnam until two years later. The observance of National Vietnam War Veterans Day was codified into Federal law in 2017. Historian’s Note: Any former OSI personnel who served in Vietnam between 1955 and 1975 who would like to contribute their personal experiences to Arnold and Thompson’s project should contact the OSI Command History Office at AFOSI.HO.Historian@us.af.mil .