Bumping this out of interest - I came across mention of Vertigo in a Twin Galaxies annual tournament manual (Video Game Masters Tournament) circa 1986. The manual specifies the required settings on the arcade game for competition, and for Vertigo it indicates that there are no possible adjustments that can be made to the game, and that one could add credits for fuel or continues:
"Pay very close attention to the start of the game. Players can very easily put more than one credit in the game to start giving extra fuel. Valid games will be one credit games starting at the beginning of the game with no continuation."