The delta wing aircraft in the opening minutes of this movie was the long-range British heavy bomber the Vulcan. It was in use from 1952-1984 and saw service in the Falkland war.
Special effects director Wally Veevers also worked on 2001: A Space Odyssey (1968), Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964), and Superman (1978).
Britain's first color science fiction film.
The test aircraft used to test the fuel is a Folland Aircraft Co. Midge the prototype for their 2-seater Gnat.
Lois Maxwell, who plays the feisty female reporter, is best known as Miss Moneypenny in the James Bond films. Her macho male lead, Kieron Moore, played the bully in a small Irish town in Darby O'Gill and the Little People (1959), starring Sean Connery.