Superman: Escape from Krypton
This roller coaster was the first to use Linear Synchronous Motors (LSMs) to accelerate the trains. The LSMs provide electro-magnetic propulsion along the horizontal section of the track. In this picture, the train has just left the LSM section of track and is starting its pitch-up to vertical.
A couple of other coasters built before this one used Linear Induction Motors (LIMs) for launching trains, and more LIM-launched rides have been built in the years since Superman debuted. LSM and LIM systems are very similar and use varying electric fields to produce magnetic forces, but LIMs have metal plates on the train while LSMs use permanent magnets mounted on the trains. LSMs are more efficient than LIMs, but they are also more complicated. The timing of applying electricity to LSMs is much more critical than the requirements on LIMs.
For its first decade of operation, the back wheels on the two cars were nearly two and a half feet across! They were the largest wheels I have ever seen on a roller coaster. This old picture shows how large the four main wheels used to be. When the ride was modified and changed names in 2011, the cars were retrofitted with smaller wheels.
©2017 Joel A. Rogers.