The National Archives has recently published never-before-seen schematics and details of a 1950s military venture, called Project 1794, which aimed to build a supersonic flying saucer, Wired Danger Room reports.

In a memo dating from 1956, the results from pre-prototype testing are summarized and reveal exactly what the developers had hoped to create.

The saucer was supposed to reach a top speed of “between Mach 3 and Mach 4, a ceiling of over 100,000 ft. and a maximum range with allowances of about 1,000 nautical miles,” according to the document.