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Black triangles over Belgium: from the gendarmes' night to the F-16s

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In the late afternoon of November 29, 1989, two Belgian gendarmes near Eupen followed a huge, dark triangle with a bright light shining at each of its three corners. This was the start of one of Europe's best-known UFO waves, during which the air force also scrambled fighter jets. Many of the reports were later given earthly explanations, and the most famous photo turned out to be a hoax, but some cases remain disputed to this day.

When: November 29, 1989
Where: Belgium
Witnesses: Gendarmes, soldiers and civilians in eastern and central Belgium, and the air force's radar stations.
Official position: According to the Belgian Air Force's 1990 report, the movement detected on radar rules out an aircraft, a balloon and a hologram, and no American stealth aircraft were in the area either. General Wilfried De Brouwer later said that the evidence is not sufficient to prove that real vehicles were in the air.

A November evening around Eupen

In the late afternoon of November 29, 1989, two gendarmes from Eupen, Heinrich Nicoll and Hubert von Montigny, were patrolling the hills above the town when they noticed a bright light in the sky. According to the Belgian public broadcaster RTBF, that evening 13 Eupen gendarmes reported a similar phenomenon from 8 different locations, and in the following hours and days nearly 150 civilians also came forward.

A UFO researcher interviewed the gendarmes nine days later, on December 9. According to that interview, the light approached very slowly and at low altitude, then passed almost directly over them. Three powerful light sources nearly blinded them. It was then that they saw that the lights sat at the corners of a huge, dark triangle and shone downward, while a reddish light pulsed in its center. The object was almost silent; only one of them thought he heard a faint hum.

The gendarmes followed the phenomenon in their patrol car. Around 18:30, from a high point, they saw it hovering motionless above the observation tower of the Gileppe Dam reservoir. Later a second, similar light formation rose from behind a row of trees. The object finally accelerated and disappeared to the northeast, toward the Dutch and German borders.

A wave lasting months

In the following months, reports came in from all over Belgium, mainly Wallonia, mostly of triangular, slowly moving objects with bright lights at their corners. The reports were collected by the Belgian UFO research association SOBEPS. The peak of the wave lasted from late 1989 to spring 1990, but accounts kept coming in for years, more than a thousand in total.

One of the unusual features of the case is that the Belgian Air Force cooperated with SOBEPS and shared its own data with it. According to RTBF, this was the first time an army had worked together with a UFO research association.

The night of the F-16s

The most famous event of the wave took place on the night of March 30 to 31, 1990, southeast of Brussels. The air force report on it was compiled by Major Lambrechts.

At 23:00, a gendarme called the military radar center in Glons to say he saw three color-changing lights over Thorembais and Gembloux forming an equilateral triangle. A gendarme patrol sent to the scene confirmed the sighting. Meanwhile the Glons radar detected an unidentified target near Beauvechain, and shortly afterward another military radar station, Semmerzake, also showed it in the same place.

At five minutes past midnight, two F-16 fighter jets took off from Beauvechain. According to the report, they made nine interception attempts between 0:07 and 0:54, and on three occasions they were able to lock onto the target with their onboard radar for a few seconds. Each time, according to the report, the target abruptly changed its movement. During the first lock, its speed increased within a short time from about 280 km/h to about 1,800 km/h, its altitude changed from about 2,700 meters to about 1,500 meters, then to 3,400 meters, and finally it descended close to the ground and the lock was broken.

The pilots never saw the object with their own eyes. Around one in the morning, the last point of light also disappeared from the view of the ground witnesses, and the jets landed before a quarter past one.

[TIMELINE: The night of the F-16s, March 30–31, 1990]

What did the air force write?

According to Major Lambrechts's report, this was the first time that several air force radars detected something in the same place where eyewitnesses saw the lights. The report rejected several explanations:

Aircraft: the measured changes in speed and altitude rule it out.
Weather balloon: the lights stayed at the same altitude for more than an hour and kept their positions relative to one another.
Optical illusion, planet: contradicts the radar data.
Hologram or laser projection: the pilots would have seen the projection, and the sky was clear.

The report also ruled out American B-2 and F-117 stealth aircraft, remotely piloted and ultralight aircraft, and AWACS surveillance aircraft. It recorded as open questions that, despite the measured supersonic speeds, no one heard a sonic boom, and that the ground witnesses eventually saw eight points of light, while the radars measured only one target at a time. According to a U.S. embassy memo, U.S. Air Force stealth aircraft were not flying in the area.

Wilfried De Brouwer, head of operations of the air force, later said that the technical evidence is not sufficient to establish that anomalous air activity took place that evening. He did, however, reject the idea that it was mass hysteria, and called the witnesses sincere.

What did the radar recordings show?

The radar data were later analyzed by several people, who did not reach matching conclusions:

In 1993, in Physicalia Magazine, Belgian physicists Pierre Magain and Marc Rémy pointed out that three echoes remained almost stationary relative to the aircraft, which may indicate a radar setting or operating error.
According to the French Wikipedia, only one F-16's radar recording survived, and the air force itself was unable to evaluate it, so it handed it over to scientists.
According to American skeptic author Brian Dunning, based on the military data, the three locks were actually on the other F-16, and the other radar contacts were caused by atmospheric reflection (so-called Bragg scattering).

Reports that were explained

Several cases from the wave were later given earthly explanations. According to a summary by Belgian researcher Wim Van Utrecht and the French-language literature:

On December 16, 1989, F-16s were scrambled, but the pilots saw only rotating searchlights reflecting off clouds. According to the police report, they were caused by a nearby disco's laser show, which the defense minister later confirmed as well.
The French research group CNEGU explained a December 1989 sighting in Ernage as very likely a helicopter, and a case in Jupille-sur-Meuse as a Sea King helicopter.
The lights of AWACS surveillance aircraft, three white lights in a triangle with a flashing red one in the middle, match the common descriptions exactly. A gendarme in Amay identified one such aircraft.

The famous photo that was fake

The wave's best-known image was taken in April 1990 in Petit-Rechain, near Verviers. The picture shows a black triangle with lights at its corners. The image was also examined by the Belgian Royal Military Academy, and SOBEPS considered it authentic for two decades.

In July 2011, the photographer told the Belgian television channel RTL that he and his coworkers had faked the image as a joke. They cut a triangle out of polystyrene foam, painted it black, attached flashlights to it, and photographed it suspended. Wim Van Utrecht had already shown in 1992 that such an image could be produced with a similar model.

The critics and the researchers

According to skeptics, the wave was largely made up of earthly phenomena and blown up by the media:

Helicopters: according to a 2008 study by French researcher Renaud Leclet, most of the cases seen from the ground can be explained by helicopters, and according to Leclet, the Eupen evening may also have been a military helicopter.
Venus: according to Dunning, the light hovering motionless over Gileppe appeared exactly where the planet Venus was as seen from the gendarmes' position.
Media and social influence: according to Belgian researcher Marc Hallet and Belgian psychologist Jean-Michel Abrassart, because of the news, people began to see and report ordinary lights as UFOs. According to Dunning, most of the November 29 reports also came in only days later, after the first news stories.

The SOBEPS researchers take a different view. Lucien Clerebaut, the association's former secretary general, told RTBF that the witnesses saw a real, material object, not a mass hallucination, but SOBEPS officially has no answer as to what it was.

The sober take

What is certain: from late 1989, for several months, many people, including on-duty gendarmes, reported triangular objects lit by bright lights over Belgium. On the night of March 30 to 31, 1990, ground witnesses and military radars detected something in the same area, and two F-16s were scrambled, but the pilots saw nothing with their own eyes. The air force documented this and gave no explanation for it.

What was debunked: the wave's most famous photo is a proven hoax. Several reports turned out to have been caused by a helicopter, an AWACS aircraft or a disco's laser light. This does not refute all the accounts, but it clearly shows that the wave mixed together many reports of different origins.

What is disputed: the interpretation of the radar data. The official report read extraordinary maneuvers into them, but according to later analysts, the signals could also have been caused by a radar operating error, the other fighter jet or atmospheric reflection. The air force's head of operations himself said that the technical evidence is not sufficient.

Strengths and weaknesses of the explanations:

Helicopters, aircraft: proven true for several cases, and a good fit for the slowly moving formations with bright searchlights. The gendarmes, however, described an almost silent object.
Venus: may fit the motionless light over Gileppe, but does not explain the triangle passing directly over the gendarmes.
Radar errors: may account for the night of the F-16s. In that case, the coincidence of the ground lights and the radar signals would be chance.
Media and mass influence: may explain many later reports. Less so the first evening, although according to critics, most of that day's reports also came in only after the first news stories.

Open question: the Belgian wave was probably not a single phenomenon, but a series of reports that came together from many different causes. For the cause behind the first evening and the night of the F-16s, there is still no explanation that all sides would accept.

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