Mindbender (Galaxyland)

The Mindbender is the world's largest indoor triple loop roller coaster. It is located in Galaxyland Amusement Park, a major attraction inside West Edmonton Mall, in Edmonton, Alberta, Canada.

Layout

Mindbender was designed by Germany's Werner Stengel and built by Anton Schwarzkopf. It was inspired by this team's previous design, Dreier Looping, a portable coaster that travelled the German funfair circuit, before being sold to a succession of amusement parks in Malaysia, Great Britain, and most recently, Mexico. Mindbender is a pseudo mirror-image of Dreier Looping, and is slightly taller, with additional helices at the end of the ride. Mindbender features shorter trains, with three pilot cars, whereas Dreier Looping usually ran with five trailer cars and one pilot car, occasionally rising to seven-car trains at busy funfairs.

The ride's layout features many twisting drops, three vertical loops and a double upward helix finale. The ride twists underneath, in between and around its supports. It also goes underneath the former UFO Maze attraction, which has been removed to make way for another roller coaster; Gerstlauer's Galaxy Orbiter, during the helix.

Often in high season, the last car on one of the trains is reversed, allowing guests to ride the roller coaster without being able to see where they are going.

Ride experience

After boarding the Mindbender, riders put on their seatbelt and lap restraints. Also, the ride operator lowers large shoulder restraints over the riders. All of the restraints keep the riders firmly secured in the seat.

After ascending the curving wheel driven lift hill, the train descends a sharp, twisting left-hand drop (sometimes referred to as a Traver drop) that climbs up to the first of four stacked block brakes. The train negotiates a second left-hand drop that is immediately followed by two vertical loops. The aforementioned process happens yet again, but the height of the coaster is decreased and the next loop is a single one.

Upon completing the final loop, the coaster train shoots along a two-layered upward before running behind the Galaxy Quest 7D theater and into the exit/entry area.

The ride length from the initial drop should normally range from one minute five seconds to one minute twenty-five seconds. Circuits times as little as 59 seconds are possible through extensive waxing of the track, and reduction in tension on the bogey wheels. This increase in speed is not permitted during public rides, as the forces on the riders becomes severe. During testing of the renovated trains in 1987, the maximum g-force of a normal run was measured on equipment bolted into the train at 5.5 G's, which occurs in the second loop.

1986 accident

On the evening of June 14, 1986, after the yellow train (train #1) completed the second inverted loop, it encountered one of three areas of uplift before the third and final loop. Missing bolts on the left inside wheel assembly of the last car of the four-car train caused the bogie assembly to disengage the track with a full load of riders. This caused the final car to fishtail wildly, disengaging the lap bars as it collided with support structures, thereby throwing off passengers and losing speed. The train entered the third and final inverted loop, but did not have the speed to complete the loop. The train stalled at the top, then slid backwards, crashing into a concrete pillar. Three people were killed during the accident and a fourth person was seriously injured.^[1]

At the time of the accident the park was packed with people who were attending a concert. The ride had shut down twice, as the operator had heard a metallic noise from the train prior to the accident. Despite running the trains empty, the source of the problem could not be located by the maintenance staff, and the regular operation of the ride resumed until the accident occurred. With the stage located atop the jumping fountains, many had a horrific view as the band played and the coaster derailed. The Mindbender was immediately closed. An investigation and inquiry was launched that revealed that there were problems in the translation from German to English of operational and maintenance information from Schwarzkopf, the German coaster manufacturer.^[2] Additional issues with quality control were found as a result of the manufacturer going bankrupt during delivery of the ride, and portions of the ride being finished by the receiver of the firm.

The root cause of the accident stemmed from the means in which each six wheel bogie was affixed to the axle. The bogie pivoted horizontally on a vertical axle, which was in turn attached to the main axle which joined each pair of bogie assemblies. The means each bogie was affixed to the vertical axle was a cap plate, located just above the track rail (1/4" clearance) and secured with four hex head recessed cap screws. As the cap screws became loose, they rubbed on the rails and eventually snapped or fell out as they rubbed along the track, releasing the retaining plate. Once all four bolts came loose, the cap plate no longer affixed the bogey to the vertical axle, and at the next uplift area, the axle came out of the bogie and the last car of the train derailed.^[3]

In addition, Mindbender crews in Canada had not been provided a special inspection order from the General Safety Services Division of Germany where the ride was manufactured. Cars were checked only by visual inspections, not by taking them out from service. Visual inspections alone would not have been adequate to determine if screws or bolts were loose due to the obscured area the bolts were located. It was discovered that one-quarter of all axle bolts on the trains were loose.^[4] No safety check had been made through the German TÜV organization. In addition, the restraint systems were also criticised for being inadequate as contact with the pillars supporting the ride disengaged the lap bars.

When the Mindbender reopened seven months later, the trains were redesigned. Existing four-car trains were converted to three-car trains, each have four bogeys on two axles (front and rear). Anti-roll back "dogs" were added to prevent the train from rolling backwards during the initial lift. Seating capacity was reduced from 16 to 12 per train. The lap bar restraint was retained, but seat belts and a shoulder headrest were added for redundancy.^[1] The design of the vertical axle was changed so that the axle became a fixed part of the bogey, and the retaining bolt was moved to the top of the axle, where it is easily inspected. Finally, maintenance checks and scheduled maintenance downtimes were significantly increased. Since the incident, the Mindbender has been accident-free.^[1]

Prior to the accident, the Mindbender had two yellow, two red, and two blue trains. After the accident, the original trains were sent to Germany to be rebuilt properly. The train which had derailed was scrapped, and the other yellow train was repainted in red and blue in order to quell any potential fear of the yellow trains which had been featured prominently in the media post-crash. The trains have been repainted since, and all three of the original colours are present.

Awards

See also

• Galaxy Orbiter

Notes

External links

• Official Galaxyland Website
• Mindbender photos and technical details on Schwarzkopf Coaster Net