Shapes of UFOs vary based on actual sightings. Here are some of the UFO shapes i gathered from different sources, I am trying to consolidate all the sightings and comparing their shapes and sizes.

THE CIGAR-SHAPED AIRSHIPS
It has been believed that before any of man’s airships flew, giant airships were seen flying in many parts of the world. Most of these sightings occurred in America during and after 1896 but they were also seen in parts of Europe including Peterborough in England.

DIRIGIBLE-SHAPED MOTHER SHIP
The person who declared and claimed to have seen an Unidentified Flying Object (UFO) and photographed it was a Polish American named George Adamski. He wrote a couple of books featured his adventures with aliens after his first UFO sighting.

In October 9, 1946 Adamski saw a ‘dirigible-shaped mother ship’ flying over his home in Valley Center, California. For him it was a sign he was directed by unseen force to settle on the southern slopes of Mount Palomar, famous for the astronomical observatory.

ROUND-SHAPED FLYING SAUCERS
In June 24 1947, an American pilot named Kenneth Arnold was famed to have seen first a flying saucer while searching for a transport airplane that have been lost in Cascade mountains.

FISH-SHAPED FLYING METALS
This is among early sightings in Russia. On December 1948. Residents in Moscow, sighted a number of longish, fish-shaped metal objects flying in the skies.
These flying objects were seen reflecting the sunlight above the capital city of Russia.

GIANT FLYING TRIANGLES
Flying triangles were first seen in the skies of Hudson Valley area of upstate New York and Connecticut in March 1983. Witnesses reported seeing ‘V-shaped’ UFOs, and often referred to them as ‘flying wings’.

They were described as extremely large, over three hundred feet in length. “It was so huge it filled up the entire sky,” one witness said. Others described them as being larger than a football field but with multi-colored flashing lights

DOME-SHAPED FLYING OBJECT
In December 10, 1963 two Royal Air Force (RAF) personnel in Cosford saw a strange domed object sweeping the airfield with a strange green beam light. This object crashed behind a hangar.

The two personnel ran to get some help but when they returned, it was nowhere to be seen. These witnesses were then subjected to a rigorous interrogation, but their story about what they witnessed could not be shaken.

TWO BOWLS FLYING OBJECT
It was January 8, 1981 when Renato Nicolai – an Italian living in Trans-en Provence, a small village in Southern France heard a strange noise from above.

During that time Nicolai was building a concrete shelter for the water pump he had recently installed behind his house.

Upon hearing the strange noise he looked up and noticed a strange object descending onto a nearby hill.

EGG-SHAPED FLYING OBJECT
On October 21 1982, a prominent metallurgist saw an egg-shaped flying object was seen hovering above a French garden. The object came to a stop and drifted over an amaranth bush for about twenty minutes then it suddenly shot itself skywards.

The metallurgist claimed he managed to get within two feet of it and at one point, manage to touch it.

EGG IN A CUP-SHAPED FLYING OBJECT
The sighting of this flying object happened in southern Australia on the night of January 20 1988 while the Knowles family was driving across the great limestone plateau of the Nullarbor plain.

FOOTBALL-SHAPED OBJECT
It was March 20, 1966 when a farmer named Frank Mannor and his son watched a car-sized, football-shaped object rise from a swampy area on his farm, then the object hovered for several minutes at a thousand feet and then it departed.

ROUND-SHAPED WITH BRIGHT HALO
When Mikhail Gorbachev was toppled from power under the so-called ‘ Second Russian Revolution’ in the summer of 1991 in the Soviet Union, files detailing UFO sightings that had taken place between 1982 and 1995 were released as the KGB opened up.

One of the sightings occurred in October 17 1983 and was witnessed by Major Kiselev as recounted by a certain Colonel Skrypnik. Col. Skrypnik was the duty officer at a top-secret installation somewhere near the city of Kursh in Central Russia.

The UFO was of a round shape with a bright halo around it and a darker center. It was seen moving randomly and had no definite direction.

DIAMOND-SHAPED CRAFT
On March 3 1991, a gang of local youth in Russia managed to photograph a diamond-shaped craft over the Tevare military base. The flying object hovered menacingly before disappearing.

UPTURNED MUSHROOM-SHAPED SHIP
Gordon Levett, who lived in a remote cottage near the village of Sudbourne sighted a UFO over Rendlesham forest in the night of Christmas Day 1980. At that time he was out in the garden with his dog. When the dog began barking, Levett looked up to see a UFO flying towards him.

He described the flying object as an upturned mushroom, glowing with a greenish-white phosphorescent light.

CONE-SHAPED CRAFT
On December 26 1980 the cone-shaped ship was sighted by US Air Force sergeant Jim Penniston and security patrolman John Burroughs in the forest near the east gate of RAF woodbridge, United Kingdom.

THE BLACK HELICOPTERS
There are debates about the origin of the so called “black helicopters”. Theorists and skeptics say these strange choppers are from secret government agencies operating underground, while others are open to some idea that these are ET in origin.