Silkworm

Silkworm is a co-operative shooter released for the arcade in 1988, and later converted to home computers within the following year. Unlike most other scrolling shoot 'em ups, Silkworm is one of the few games that has two players control a different vehicles, with a choice among a helicopter and a jeep. While playable by one person, the two vehicles can co-operate by covering each other's blind spots.