DVD_TheGreatAmericanScreamMachine[DVD: Horse Creek Productions – 1972 – 26 mins]. The building of a classic wooden roller coaster. The Great American Scream Machine was the tallest roller coaster in the world when it opened back in 1973 at Six Flags Over Georgia (Austell, Georgia). This beautiful classic was designed by John Allen of the Philadelphia Toboggan Company, and in this 1970s vintage documentary, see the design, construction, testing and opening of this amazing coaster. Features interviews with John Allen and his team. ANDY SHINE SAYS: The film quality is pretty poor, but then it was the 1970s! ANDY SHINE’S RATING: Fair.