Screamer is a term in
amusement parks used to describe a
roller coaster train that does not stop in the station but rather continues on the
roller coaster track again. This occurs when the
station brakes remain open while the train's brake fin passes completely through all sets of brakes. The brake fin is a metal
sheet connected to the bottom of each car in the train onto which the station
brakes clasp to hold the train in place.
Screamers are most often seen on antiquated children roller coasters as the control system for these rides is often made for manual hand brake control rather than a simple push-the-button operation. The most common way to create a screamer on a hand brake system is to not close the brake while the train hits the first set of station brakes. On a control panel operation system generally built before mid 1980s, it is also possible to create a screamer by holding the station brake button until the train passes through. Modern control panel operation systems will automate the terminal part of the braking process as long as the button is pressed until the train completely stops. Screamers will not occur during a power outage because station brakes (unless operated by a hand brake which should not be affected immediately by a power outage) naturally rest in a closed position and require hydraulics to open.
Screamers may possibly be beneficial if:
- the train is already past the normal boarding alignment and it is more dangerous for the riders to exit than to ride once more.
- the roller coaster is a children's ride and the parents will yell at the operator to keep the ride going until they get back.
- all the station brakes will not close tight enough for the train to stop, in which case the trim brakes (the ones before the station brakes to stop additional trains) should be used.