Boomerang (roller coaster)

Boomerang is a coaster type made by Vekoma, named after the original boomerang. The first Boomerang began operation in 1984 at Rafaela Padilla in Puebla, México (which has since been moved to Six Flags México), and it has become one of the most repeated roller coaster designs in the world, with 41 Boomerangs operating as of 2011, another two "Standing but not operating" or in storage, and one currently under construction.
Information.
The Boomerang operates with one train with 7 cars, each capable of carrying 4 people (28 people per train). The ride starts with the train being pulled backwards out of the station, up a lift hill by a catch-car. When the catch-car reaches the end of the lift hill, it releases the train, which rolls down through the station, then into a cobra roll. After the cobra roll, it goes through a loop after which it clicks onto a chain on the second lift hill. When the train reaches the end of the second lift hill, the chain is moved down, which causes the train to roll down (as it is not attached to the chain anymore) and do the same track backwards.
Problems.
Boomerang coasters have sometimes stalled, often in the cobra Roll element. As a precaution, many Boomerang coasters, are built with an access platform just under the cobra roll. Also, sometimes the train gets stuck on the second lift hill.