1980s Hudson Valley sightings During the early 1980s, several hundred people claimed to have witnessed UFOs flying over, or near to, the
Hudson River in New York state. These sightings involved hovering or slowly flying V-shaped objects rimmed with colorful lights. Several pilots claimed responsibility for these UFOs, reporting that the objects, some tracked to a local airport and parking lot, were
ultralight aircraft flown in formation.
1989–1992 Belgian wave The Belgian UFO wave began in November 1989. The events of 29 November were documented by over thirty different groups of witnesses and three separate groups of police officers. All of the reports related to a large object flying at a low altitude. The craft was flat and triangular, with lights underneath. This giant craft did not make a sound as it slowly moved across the landscape of Belgium.
The Belgian UFO Wave of 1989–1992 – A Neglected Hypothesis discusses some sightings that helicopters can explain. Most witnesses reported that the objects were silent. This report argues that the lack of noise could be due to the engine noise in the witnesses' automobiles or the strong natural wind blowing away from the witnesses. Black triangle UFOs have been claimed to be visible to radar. During the 1989–1990 Belgian UFO wave, two
Belgian Air Force F-16s attempted to intercept an object detected by radar, but the pilots did not report seeing an object. This entire Belgian UFO wave, however, has been disputed by skeptics and was revealed to be a hoax.
1997 Phoenix Lights incident A widely reported appearance(s) of black triangles involved the "Phoenix Lights" events, during which multiple unidentified objects were observed near
Phoenix, Arizona and videotaped by both the local media and residents beginning on Thursday, March 13, 1997. Some observed objects/lights appeared to be grouped in a large "V" formation that lingered for several minutes. Some residents reported one of the black triangles to be over a mile wide and that it drifted slowly over their houses, blocking out the night sky's stars. An official report from the US Air Force concluded that the military had been locally testing aircraft-launched flares during that period.
2000 Southern Illinois incident The "St. Clair Triangle", "UFO Over Illinois", "Southern Illinois UFO", or "Highland, Illinois UFO" sighting occurred on January 5, 2000 over the towns of
Highland,
Dupo,
Lebanon,
Shiloh,
Summerfield,
Millstadt, and
O'Fallon, Illinois, beginning shortly after 4:00 am. The incident was featured in several television shows including
Seeing is Believing, a
Discovery Channel special
UFOs Over Illinois, and an episode of the
Syfy series
Proof Positive.
Sufjan Stevens included this incident in the song "Concerning the UFO Sighting Near Highland, Illinois" from his 2005 album
Illinois. The
FAA said sighting reports may have been due to an advertising blimp operated in the area by the
American Blimp Company.
2008 Stephenville, Texas Around 8 January 2008, there was a mass sighting in
Stephenville, Texas. In the 2023
Netflix documentary series
Encounters, it is claimed that there were black triangles and inside were what looked like insects or a
praying mantis. ==Military aircraft==