A twister roller coaster is the generic name given to any roller coaster layout which tends to twist or interweave its track within itself several times. It is essentially the opposite of an Out and Back roller coaster, which is often a much more simplistic layout. Twister roller coasters often have the illusion of having small or tight clearances due to the track usually travelling through several support structures. This is known as a head chopper effect. * v * t * e