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The flying saucer -

Unlike a fighter jet or a bomber, the flying saucer is an aircraft design that is yet to be mastered. This, however, never stopped engineers from trying to make them.

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Aerodynamics -

But first, it’s important to understand why a circular wing might not be a great idea. As far as aerodynamics is concerned, the lift-induced drag makes circular wings inefficient.

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Stability and control -

The flying saucer poses problems when it comes to stability and control. The arm available is pretty small, making it harder to control.

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Stability and control -

For designs like the flying saucer, keeping stable at low speeds could be an issue, unless the entire structure spins, like a frisbee.

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How about spinning discs? -

Sure, this could potentially work, but it would have to be unmanned, as a pilot is unlikely to be able to endure it.

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Experiments -

But despite all the challenges, some inventors have tried to make their own versions of flying saucers. Let’s take a look at some of them.

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Lee-Richards annular monoplane -

The first experiments with a disc-shaped aircraft date back to 1913 with the Lee-Richards annular monoplane.

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Lee-Richards annular monoplane -

An annual or flat ring-shaped wing aircraft was built by Cedric Lee and G. Tilghman Richards, and manufactured by James Radley (here pictured in a monoplane).

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Lee-Richards annular monoplane -

The Lee-Richards annular monoplane was taken to Famine Point at Heysham, UK, for trials, but its performance was deemed “not particularly satisfactory.”

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Arup S-2 -

While not a flying saucer just yet, the Arup S-2 was a low aspect ratio wing aircraft that deserves a mention. It was developed in the US and first flew in 1933.

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Vought V-173 -

Following the events at Pearl Harbor, the US Navy started working on the Vought V-173 "Flying Pancake."

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Vought V-173 -

The aircraft had a flat body shaped like a pancake and an "all-wing" design.

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Vought V-173 -

The Vought V-173 was developed by aeronautical engineer Charles H. Zimmerman under World War II’s Vought XF5U program. It had its first flight in 1942 and was retired five years later.

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Vought XF5U -

This US Navy fighter aircraft shared some characteristics with the Vought V-173, but it was considerably larger and heavier.

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Vought XF5U -

The Vought XF5U "Flying Flapjack" was developed by Charles H. Zimmerman (pictured).

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Vought XF5U -

The XF5U-1 wasn’t ready until June 1945, so its use to serve in World War II was redundant.

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Nazi UFOs -

There were rumors that German aeronautical engineers were developing a flying saucer of their own. Could these have been the foo fighters witnessed by both Allied and Axis pilots during the war?

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Aerodyne RC-360 -

French aeronautical engineer Rene Couzinet designed the Aerodyne RC-360 in 1955.

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Aerodyne RC-360 -

A 60% concept scale model of Couzinet’s radially symmetric aircraft was built, but the world never witnessed a full-scale one. How it would have worked, we will never know.

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Projects Y and Y-2 -

Projects Y and Y-2 were the first steps in the development of flying saucers, first by Canada, and then by the US. Pictured is the Project Y mock-up in the Experimental Flight Hangar in 1954.

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Avro VZ-9-A Avrocar -

The Avro VZ-9-A Avrocar was developed as a secret US military project during the Cold War. Developed by Avro Canada, the aircraft was first tested in 1959.

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Avro VZ-9-A Avrocar -

The Avro VZ-9-A used a single "turborotor" to provide lift and thrust. It was designed to reach high speeds and altitudes, but that didn’t quite happen.

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Avro VZ-9-A Avrocar -

The Avro VZ-9-A was initially intended to work as a fighter aircraft by the US Air Force, but it ended up being taken up by the US Army as a tactical combat aircraft (similar to a helicopter).

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Avro VZ-9-A Avrocar -

Pictured are US Army Avrocars portrayed as "flying jeeps" in company literature.

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Avro VZ-9-A Avrocar -

The concept was developed by British aircraft designer "Jack" Frost. Frost went on to register a number of patents on aircraft propulsion and control, such as the air cushion effect used in flying saucer-type aircraft.

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Avro VZ-9-A Avrocar -

Pictured is an image taken from the Avro VZ-9-A manual.

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Flying saucers of the 21st century -

In 2019, Romanian inventor Razvan Sabie and scientist Iosif Taposu unveiled a new All-Directional Flying Object. "The aerodynamics behind this aircraft is the result of more than two decades of work," Sabie said.

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All-Directional Flying Object -

"And is very well reasoned in hundreds of pages and confirmed by computer simulations and wind tunnel tests," he added.

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Is it alien technology? -

Flying saucers are inherently linked to UFO sightings. The technology is not easy to master, and so far it hasn’t been developed on a commercial scale. This has led many ufologists to believe that such advanced technology can only come from outer space.

Sources: (24/7 Wall St.) (Popular Mechanics) (Science Alert) (Hush-Kit)

See also: The most famous UFO sightings in the world

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