If my memory is correct, Kings Island north of Cincinnati Ohio had one of
the first "suspended" coasters in the U.S. back in the early eighties.  It
was shutdown for problems more than it ran, and after one of the two
person cars fell off, they tore it down.  They called it "The Bat".  I
did manage to ride it once or twice and it was a pretty 'brusing' experience
(I'm 6' 3.5" and I didn't fit too well in the small space of the car).

Regards,
Michael