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General Category => Other Parks => Topic started by: cowboy on June 22, 2021, 11:55:34 AM

Title: SFA - Harley Quinn - Support Vibration
Post by: cowboy on June 22, 2021, 11:55:34 AM
Did you see where the Harley Quinn ride at Six Flags America malfunctioned causing one of the support columns to begin harmonic vibration? This kind of vibration could have busted the ride completely apart.

Here's a tweet that has video of the support vibrating: https://twitter.com/aoEngineering/status/1406805603792654336?s=20

Jay
Title: Re: SFA - Harley Quinn - Support Vibration
Post by: shavethewhales on June 22, 2021, 03:43:22 PM
Seems like a fairly major design failure that this could happen. The supports always seemed minimal with no cross bracing on the sides. To be fair though, the column did not collapse, so obviously a high factor of safety was built in.

I wonder if the ride will be modified in the future, and if this will affect the many other models scattered around the world.
Title: Re: SFA - Harley Quinn - Support Vibration
Post by: Fergy328 on June 23, 2021, 11:20:51 AM
Someone commented about what they think happened and it, at least to me, makes the most sense:

"It looks like the brake was engaged but the motor kept trying to run, and the applied force synced up with the natural frequency of the structure, thus causing resonance. That is extremely dangerous."

As for why the operators didn't e-stop the ride, apparently Six Flags doesn't allow their ops to do that unless a member of management is present, which seems like a very problematic choice.
Title: Re: SFA - Harley Quinn - Support Vibration
Post by: shavethewhales on June 24, 2021, 10:22:16 AM
Surely they can E-stop as needed. It doesn't make sense to have to call management to do an emergency procedure. That's like saying no one can leave a burning building until the fire department comes. I have a feeling they warn heavily against unnecessary e-stops though. Considering they have so many kids running things it could be easy for them to freak out and e-stop over nebulous things. In this case, since this is so out of left field, the kids probably didn't know what to do. Obviously better training is needed, as always. Hard to do when they are only there for a few months.
Title: Re: SFA - Harley Quinn - Support Vibration
Post by: Swoosh on June 24, 2021, 05:45:18 PM
Hit the dang E-Stop.  The ride ops have been torn apart on Reddit and TikTok for not hitting the E-Stop.