How did El Toro happen?

I recently saw El Toro is going to be back for the spring of 2022. It got me thinking: I remember waaaaaaay back in my youth I watched a documentary on roller coasters, wood coasters specifically, and the documentary mentioned if a wooden coaster’s measurements were off by something like 1/32nd of an inch, the coaster could be four inches out of alignment by the top of the ride. I also remember Toro was a “plug and play” design, laser cut for each piece to fit together more accurately and create a smoother ride experience and easier build. In either case though, wooden coasters just naturally have some variance from ride to ride due to multiple factors.

My point in all this is how on earth did El Toro’s entire back upstop wheel and axle pop out and end up above the track last year? Wood has a ton of variance, yeah, but Toro was designed to minimize that. Could things have misaligned that badly over the years?

if you have a good explanation or theory, I’d love to know! Layman’s terms please. *laugh*

Best possible theory I've seen comes from ElToroRyan - and he explains it well, in layman's terms - here:

But he didn't talk about the block zones?

For those of you who are unfamiliar, a block zone is a section of ride that only one train may occupy. At the end of a block zone is a method to stop the train in case the block zone ahead is still occupied. This is the safety system that prevents roller coaster trains from colliding with one another.

Judging from ElToro Ryan’s video alone, the people in the back seat were very very lucky to be unharmed. Really the whole train could have possibly been affected by the fishtailing back end it seems.

I have to say I’m not super surprised though. I’ve felt like that noise Toro makes as it crests each airtime hill was the wheels fighting to keep the coaster on the track. For a wheel to (theoretically) fall off or break off definitely does not seem out of the realm of possibility to me. Thanks RavenPhile for the find!

I think "fighting to keep the train on the track" is an overstatement. Those wheels aren't enduring any greater forces than the road wheels enduring at the bottom of every valley. To a human a negative G for an instant feels like the train trying to launch you to the moon. For wheel assembly, it's basically nothing.

bunky666 asked “How did El Toro happen?”

Well you see, when a mommy roller coaster and a daddy roller coaster love each other very very much…

I clicked this topic to write the exact same thing. LOL

Whereas I keep wanting to go with

"Well, first the Earth cooled. And then the dinosaurs came, but they got too big and fat, so they all died. And then the Arabs came and they bought Mercedes Benzes..."

ApolloAndy said:

I think "fighting to keep the train on the track" is an overstatement. Those wheels aren't enduring any greater forces than the road wheels enduring at the bottom of every valley. To a human a negative G for an instant feels like the train trying to launch you to the moon. For wheel assembly, it's basically nothing.

I’d normally agree with you, but I’ve never heard another wooden coaster make that sound to that degree. I’m of course not an expert, but it seems like an abnormal sound and one that indicates a much stronger pull and/or grinding on the crests of the hills. Wouldn’t the weight of the trains and that amount of force upward be much more stressful on the structure and the vehicles?

That's just the train riding on the upstop wheels. The upstop wheels are significantly smaller than the road wheels, and I believe they're steel vs. urethane coated.

If you're ever riding an airtime machine with PTC trains, you can notice the upstops grumbling a lot, too, but the sound is masked by the other sounds of a wooden coaster.

I always liked hearing the upstops spinning like crazy on Mean Streak when you hit the brakes outside the station.

I always noticed the same thing on the original Texas Giant if it stopped on the mid course and in the first set of brakes at the end.

Remember that down force on the track is transmitted through a horizontal ledger every few feet which leads to the ground. Forces pulling up on the track don't have that luxury, as there is literally infinite space for the pieces to move.

I’m not a structural guy but wouldn’t the upward forces pull on those same horizontal ledgers which then pull on those same columns going to ground which then pull on the anchor bolts? I’m not following the infinite space. If something breaks I guess there is infinite space. But looking at down forces, if something breaks, while there isn’t infinite space to fall, you don’t need infinite space to have a bad result.

I would wager that the compressive strength of wood is a great deal higher than the tensile strength.

You lose. (Partly.)

(For white pine, along the grain, tensile strength is 11300 psi and compression strength is 4800 psi. Perpendicular to grain, compression strength is greater, but I think we're mostly talking about the vertical members of the bents.)

Shades: No, because the down force compresses everything in between. There's nowhere for it to go. Upward force is held in place by the same structure, sure, but if it fails, like I said, there's no limit to how far away from the structure it can get (gravity not withstanding). The upward force is limited only by the wooden track, the layer of metal on it, and the fasteners that tie the track down. Downward force is limited by the ground with structure in between. The ground is very compelling.

Let me go a step further. Let's change the vectors. We've all seen coaster structures move in a banked turn when the train goes by. The structure does its best to keep it in place. Now pretend that same banked turn is up against a quarry wall. It doesn't go anywhere, right? The track may bow a little between the bents, but most of the force pushes on the structure which pushes on the ground. Take away the quarry wall, and the structure again moves a ton.

I don't know what happened with El Toro, but if an upstop gets out, my assumption is that either the upstop axel failed or the track rail got loose or split.

hambone said:

You lose. (Partly.)

Only 2.3% shrinkage? I'm envious.