The official story is that he flew too high in a plane and ran out of oxygen while chasing Venus or a weather balloon, but that simply doesn’t wash for his grandson Terry and the rest of the Mantell Family.

Thomas Mantell died on January 7, 1948, when his fighter plane fell out of the sky in Kentuck

The wreck of Mantell’s plane which fell to the ground in farmland near Franklin

Captain Mantell’s P-51 Mustang he was flying on the day of the chase

“[The government] have tried to say he was a fly boy, that he was like Maverick in Top Gun, but he was just doing what he was told to do,” Terry told The Sun Online.

“He had two sons, he was married to his high school sweetheart, he was an experienced pilot, and he died chasing something he thought was a threat to America.

“What was it? I am not sure.”

Mantell was a decorated World War 2 veteran who had been awarded the Distinguished Flying Cross for his heroics and even served on D-Day.

Yet despite dodging death from Nazi anti-aircraft guns, the young dad died when his P-51 Mustang mysteriously fell out of sky just miles from where he was born in Franklin, Kentucky.

Captain Mantell – who was flying a training mission at the time with three other pilots – was dispatched by Godman Army Airfield at Fort Knox after reports of an unknown object on January 7, 1948.

The mysterious shape in the sky was spotted by cops and then airmen stationed in the base’s control tower.

Some witnesses described the shape in the sky as a “300 ft disc” while others said it was a “flaming red cone trailing a gaseous green mist”.