Like most conflicts, the Vietnam War is chock full of myths and legends. Some legends are generated by the secretive nature of the war, such as the rumors of Soviet special forces, while others are generated through documented instances, such as the stories of American defectors fighting alongside the Communists. But one myth doesn’t sound very mythical at all upon first hearing, and that is the rumors of the “enemy helicopters.”

From the sound of it, the term “enemy helicopters” in the context of the Vietnam War might initially sound like an American soldier or pilot referring to helicopters used by Communist forces. However, the Viet Cong had no helicopters to speak of, while the North Vietnamese mostly used the Soviet Mi-4 and Mi-2 helicopters for transport within Laos and North Vietnam, which would have been behind-the-lines and away from combat. The Vietnam People’s Air Force (the air force of North Vietnam) operated some MiGs, but these would have been used for air defense over North Vietnam as well. For all intents and purposes, the average American soldier would never have seen an actual Communist helicopter or even been aware the North Vietnamese had helicopters in their inventory.

So where did the term “enemy helicopters” come from? In actuality, “enemy helicopters” was often used by American servicemen to refer to any aircraft that the soldiers were unable to identify as friendly – unidentified flying objects.

A former U.S. Air Force intelligence officer, Capt. George Filer (who had top-secret clearance while in the military) made daily briefings to the deputy commander for air operations in Vietnam, Gen. George S. Brown, and said “enemy helicopters” allowed servicemen a way to discreetly report something that shouldn’t be there without having to outright report a UFO. This term was apparently put to good use as UFO sightings, particularly along the DMZ area at night, were not uncommon. In fact, the military brass was interested in the capabilities of these strange objects.

“You’d have an aircraft flying along, doing around 500 knots and a UFO comes alongside and does some barrel rolls around the aircraft and then flies off at three times the speed of one of the fastest jets we have in the Air Force. So, obviously, it has a technology far in advance of anything we have.”

In some cases, the UFOs were merely seen observing American aircraft, such as an incident involving Lt. Frederick Fox, an A-4 Skyhawk pilot who claimed to have his own close encounter during a mission in 1964 in Vietnam. During a flight, the saucer-shaped UFO came just off the wing of Fox’s aircraft and briefly followed alongside his aircraft before it “de-materialized.” Though the UFO and Fox seemed to merely observe each other, the encounter left Fox with a “peaceful” feeling and the UFO gave Fox the impression that it was protecting him.

However, other incidents were less than peaceful, and surprisingly (when compared to other brief UFO sightings) actually resulted in conflict between human combatants and the objects.

In one instance in the summer of 1968, a pair of American patrol boats were on a routine night patrol near Cua Viet along the DMZ between North and South Vietnam. Around 12:30 a.m., PCF-12 received a distress call from PCF-19, another patrol boat operating in the area which claimed they were attacked by unidentified lights, referred to as “enemy helicopters.” PCF-12, commanded by Lt. Pete Snyder, moved to PCF-19’s position to offer assistance and saw two glowing circular bright lights hovering over PCF-19, when one of the objects emitted a “bright flash of light” which caused PCF-19 to explode in a cascade of debris and water. The two lights then sped away toward the sea as PCF-12 picked up two wounded survivors who said the lights had been trailing their boat for miles before PCF-19 decided to fire upon the seemingly threatening objects, which was when the object destroyed the boat.

PCF-12 continued to patrol upriver and were eventually tailed by the same two lights, which hovered on the port and starboard sides about 300 yards away 100 feet above the water. After the crew of PCF-12 were informed by headquarters that no aircraft were operating in the area, Snyder determined the aircraft were not friendly and ordered the crew to fire on the lights. The weapons did not have any visible effects on the lights which continued following and flickering in the dark, with second engine man Jim Steffes describing the objects as possessing “a rounded front like an observation helo” with “two crewmen sitting side by side.” At the nearby base Point Dume, tracers were fired at other blinking circular lights in the sky above the base, and a group of F-4 Phantom jets eventually converged on the area, chasing away the lights following PCF-12. The incident was also confirmed by Bill Cooper, a former patrol boat captain who served in Vietnam from 1967 to 1969.

Surprisingly, at the same time the ship HMAS Hobart of the Royal Australian Navy was patrolling near Tiger Island in the South China Sea. Up to 30 slow-moving lights were reported hovering near the ship, which were initially identified as Soviet helicopters. Phantom fighters and anti-aircraft fire on the ground drove the aircraft out to sea, with several other military vessels contributing to the chase as well – unfortunately, a U.S. Navy swiftboat was hit by friendly fire and five to seven American crewmen were killed. The next day, a search of the area reported no wreckage of helicopters or any other aircraft were recovered.

This was just one of many instances that occurred in Vietnam.

In 1966, an American base at Nha Trang experienced a close encounter when a few thousand soldiers were outdoors to watch a movie. Suddenly, a light appeared and seemed to fly at about 25,000 feet before descending to about 300 feet off the ground. While hovering, the light caused the engines in some nearby bulldozers and A-4s preparing for takeoff to malfunction before the UFO shot into the sky and disappeared – at which point the equipment returned to functioning normally.

In another instance in 1967, soldier Pete Mazzola was on patrol when his patrol was pinned down by Communist forces. While staying low, the soldiers saw “bright objects” rise up over the paddy fields and hover in the air. Both American warships to the south and Viet Cong forces fired at the lights, though Mazzola said the shells seemed to explode just short of the lights. Throughout his tour, Mazzola claimed he saw many “meteors” did moved unlike normal shooting stars and eventually founded the Scientific Bureau of Investigation after the war to investigate UFOs and paranormal events.

In 1970 at Lone-Jon Island, a five-man reconnaissance team reported being followed over the course of five days by bright disc-shaped lights only four-inches by four-inches, yet possessing a “black eye.” When shot, the lights would turn a red color with the “eye” turning green. The lights were capable of darting, zig-zagging and occasionally came within five feet of the team. When the team returned to headquarters, the soldiers were told to forget about the incident, with their equipment searched and sometimes confiscated, including photos allegedly taken during the mission.

In the summer of 1968, a U.S. Army Ranger recon team was operating in the “North Country” and was aware of a Viet Cong unit positioned in a hill opposite of the team’s position. At around 2 a.m., a bright blue light silently hovered toward the Rangers’ position when North Vietnamese Army forces began firing at the light. The rounds fired at the object seemed to have no effect, as the object emitted an extremely bright light toward the gunfire which silenced the Vietnamese positions before the light simply hovered away. The Rangers investigated the enemy camp the next day, and found multiple weapons seemingly abandoned with damage showing signs of heat or even melting while piles of ashes and possibly bones were also reported.

Another story commonly told is a supposed incident in 1970 wherein alleged former Green Beret captain William “Bill” English, claimed his special forces team was deployed to a B-52 crash in the Laotian jungle after the bomber had a UFO encounter. According to English, the mission was to secure the crash site, rescue any surviving crew members, retrieve any evidence (such as the flight recorder) and destroy the wreckage.

“When we got there, what we found was pretty bizarre. First of all, the aircraft was fully intact. It had not crashed. It looked like a big hand had grabbed it and set it down in the jungle. There was no crash trail or anything. The hatches were sealed. We didn’t know how to get into the damn thing, so we popped a hatch with a det-cord charge. We found the crew still in their seats in their harnesses, horribly mutilated. And there was very little blood, when there should have been pools of it on the deck of the aircraft.”

After photographing the bodies, the team collected the dog tags along with other pieces such as maps and promptly destroyed the aircraft, with the evidence from the mission being turned over to Military Assistance Command – Vietnam, in Saigon. Despite the fantastic and mysterious nature of English’s story, it is important to point out that there are many aspects of the incident that detract from its authenticity, such as a lack of other witnesses from the mission, no B-52s deployed over Laos in 1970, etc.

If such incidents involving UFOs really did occur and involved the loss of life, or if UFO sightings among servicemen were an open secret, then why is it that such phenomena during the war has seen so little attention? Fox alleged that there is a document titled “JANAP 146 E,” which includes not only the protocol and terminology on how to identify things such as aircraft, submarines, UFOs, etc. but states that the charges for discussing the UFO phenomenon includes a 10-year prison term and a $10,000 fine. While the document available on the NSA’s website does not specify the prison term and fine, such punishments could be part of the reason why servicemen do not come forward with their sightings.

There is also a more rational explanation for the “enemy helicopters,” and that could be aircraft deployed to areas where they officially aren’t supposed to. For example, the Laotian Civil War was being fought covertly by the CIA at the same time the Vietnam War was drawing most of the world’s attention, so there could have been aircraft deployed to areas where unofficial or black operations are being conducted. This does not explain though the instances where trained pilots and servicemen were watching aircraft outperforming their own vehicles, or experiencing technology suddenly malfunction.

The Vietnam War isn’t the only conflict which saw reports of UFO activity, with the “Foo Fighters” of World War II being the most famous. What is unusual though is the apparent regularity with which American forces reported UFOs in Vietnam, as well as the multiple time soldiers on the ground (instead of just pilots in the sky) reported interacting with these strange objects. Until such events are officially declassified, the true nature of “enemy helicopters,” like so many other secretive aspects of the Vietnam War, may never truly be revealed.