Great American Scream Machine was a steel roller coaster located at Six Flags Great Adventure in Jackson Township, New Jersey. The 173-foot (53 m) tall ride was built in 1989 as the fastest looping roller coaster in the world, reaching speeds up to 68 mph (109 km/h). It was designed by Ron Toomer and built by Arrow Dynamics, which built its sister coasters Shockwave (dismantled in 2002) at Six Flags Great America in Gurnee, Illinois and Viper at Six Flags Magic Mountain in Valencia, California. All three coasters have three loops after the lift hill, a batwing, and a double corkscrew. Scream Machine succeeded its sister coaster Shockwave as the tallest and fastest looping coaster in the world, but relinquished the claim to its other sister coaster Viper. Both Shockwave and Scream Machine only held the claim for one year. Although a roller coaster of the same name exists at Six Flags Over Georgia, that ride is an out and back wooden roller coaster. In 2011, the ride was replaced by Green Lantern, a stand-up roller coaster, which is still on operation as of 2020.