Source: http://www.megalextoria.com/wordpress/index.php/2017/04/28/project-stealth-fighter-commodore-64/
Project Stealth Fighter is a combat flight simulator that was released in 1987 for the Commodore 64. It was also available for the ZX Spectrum in the U.K. It was based on a fictitious U.S. Air Force fighter aircraft that was rumored to exist based on the fact that the number 19 seemed to have been skipped for fighter designations. Before this, all fighters had been consecutively numbered (except for 13 which was skipped due to it being an unlucky number).
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