I am familiar with this incident.
Some background info first. Himalya is a common fair/carnival ride. The ride has 20 passenger cars connected in a circle. These cars rotate around on an undulating track (peaks and valleys, ups and downs) The ride can travel either forward or backwards -controlled by the operator.
As with any spinning ride, centrifugal force is what gives the rider the thrill...and -here is the important part- this centrifugal force also pulls the riders away from the centre (if you are the rider seated on the outer seat of the three person car -you're going to get squished by the others in your car).The model at Calaway had a single lap bar restraint.
The ride spins. Centrifugal force is at play. There is metal fencing on the outer perimeter of the ride and in the queue (also a factor, as you'll see shortly).
At least one of the girls was below the ride manufacturer height restriction for the ride (although I am 99% certain that both girls were too small).
The adult and 2 young girls were loaded into the car -with the heavier adult occupying the INSIDE seat and the 2 smaller and lighter girls on the OUTSIDE.
Newer models of this ride (it is still being manufactured) are set for a max of 12rpm as the speed for the ride. However, this was an older model where the operator could actually dial it up beyond the 12rpm level they are supposed to operate at (I think 16rpm was the highest the old dial could go -and it wasn't all that uncommon for operators to make it a bit more fun by exceeding 12rpm).
The ride started. People screamed "we want to go faster". The operator did what most of them did -they obliged them and turned up the dial a bit.
The centrifugal force caused the heavier adult to squish against the 2 young girls. BOTH girls popped out of their car while the ride was at full force (unsure how fast -but the investigation proposed that it was beyond the "safe" 12rpm level.
The 2 girls were propelled at speed into (and through) the steel fencing around the ride/line-up. Both girls were pretty badly injured and both required ambulance transport.
The subsequent investigation found that operator error was likely to blame as A) the girls were below the required height to ride, and B) there was evidence to suggest that the ride had operated beyond the 12rpm speed which was the standard to which they were trained.
Calaway packed up the ride and sold it in what was likely a PR move. Don't know who bought it.
At the time, amusement rides were regulated by the Alberta Elevator and Fixed Conveyances Act. An investigation is absolutely required after any incident of this nature. There would most certainly be information on the investigation's findings on public record -if you're willing to do the legwork. The government has since semi-privatized the inspection process. AEDARSA is now the regulatory body for this stuff.
I have no idea what the extent of the injuries was. Rumour had it that there was a significant settlement involved.
One very interesting thing I found is that Calaway Park seems to have conveniently "forgot" about the Himalaya ride accident and claim that there has only been one incident on Park and that it did not result in any injuries (the little kid's "Super Jet" ride -which apparently kicked into gear by itself while kids were in the process of loading or unloading).
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