Six Flags spokeswoman Nancy Chan confirmed to ABC7 News that the Superman ride got stuck at 2:30 p.m. She said the two-car ride holds 12 people total.
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The roller coaster car got stuck at the tallest point in the ride. The people were stuck sitting upright and not upside down.
Crews worked on the coaster car undercarriage. Rescuers say no one needed medical attention, but they did pass out water and sunscreen. In the end, the coaster car safely came down and all the passengers walked away unharmed.
"With the plan of releasing the train, if possible, that's our first plan of action. That's the safest. And second would be to rescue them individually if they had to. We were able to fortunately go ahead and release the train," said Vallejo Batt. Chief Raymond Jackson.
"We had one of our mechanics on the scene, engaging with the guests, within 15 minutes and as best as we can determine there was no mechanical situation whatsoever," said Six Flags Discovery Kingdom president Dale Kaetzel.
The car did seem to release OK and get down safely.
Jackson said they have trained with the big crane used in this rescue. Since this is a new ride, OSHA had asked that the amusement park keep the crane onsite and have an emergency plan in place. Crews say they actually conducted this kind of mock rescue scenario a few weeks ago and they say it was helpful to have that training to go on.
The attraction has been shut down until further notice.