Tighten the strap on your tinfoil hat: Recently declassified documents show that the US Air Force was working on, and perhaps had already built, a supersonic flying saucer in 1956.

The aircraft, which had the code name Project 1794, was developed by the USAF and Avro Canada in the 1950s. One declassified memo, which seems to be the conclusion of initial research and prototyping, says that Project 1794 is a flying saucer capable of “between Mach 3 and Mach 4,” (2,300-3,000 mph) a service ceiling of over 100,000 feet (30,500m), and a range of around 1,000 nautical miles (1,150mi, 1850km).

As far as we can tell, the supersonic flying saucer would propel itself by rotating an outer disk at very high speed, taking advantage of the Coandă effect. Maneuvering would be accomplished by using small shutters on the edge of the disc (similar to ailerons on a winged aircraft). Power would be provided by jet turbines. According to the cutaway diagrams, the entire thing would even be capable of vertical takeoff and landing (VTOL).

These images (two more at the end of the story) come from the US National Archives, which is tasked with preserving important records and documents — including declassified military documents. It isn’t clear why it has taken some 64 years for Project 1794 to be declassified, though it does follow on from the declassified news in 2008 that the US government has been monitoring UFO activity for more than 30 years. There are apparently two whole boxes of Project 1794 documents — but only the four images shown here have been digitized.

Without a deeper look inside those boxes, we can’t be sure that Project 1794 ever made it off the ground. It’s worth noting that Avro Canada also worked on the VZ-9 Avrocar, though — which is basically the same as Project 1794, but a lot smaller. The Avrocar was originally specified for a max speed of 300 mph and a service ceiling of 10,000 feet — but in practice, it never got more than three feet off the ground or flew faster than 35mph.

Despite the Avrocar’s failures, it is clear that the US government was indeed working on aircraft in the 1950s that resembled flying saucers. Suffice it to say, the US might also have been working on flying saucers back in the ’40s, around the same time as the Roswell UFO incident.

Ultimately, though, the fact that we use fixed-wing aircraft today is a good indicator that flying saucers, while cool, just aren’t that functional. If flying saucers were somehow faster or more efficient or capable of lifting heavier loads, we would almost certainly see them in a commercial setting. Sadly, while some UFO sightings may have indeed been Project 1794, it’s unlikely that they were anything more than experiments carried out by humans, not aliens.

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