Incident on The Smiler 02/06/2015

[Nemesis94]

@Nemesis94 all good reasons why a stall could happen, except the burst tyre, I am not aware of any coaster with inflatable wheels, they are solid plastic or rubber usually (different compounds of plastic give different speed).

I am no expert so I am sure there are engineers that know a lot more!

The plastic/rubber wheel tyres can burst (or explode for want of a better word) if they get too hot/old. The little "mud guard" on the back of the Smiler's wheelset is not just for aesthetics, its to protect the riders from bits of plastic that could fly off if it happens.

Most coaster don't need these, as the floor of the ride car will protect you in such cases (hence why the Smiler often runs without them). The B&M floorless coasters have no such protection, hence each of the main running wheels has a little metal guard around it (as visible here http://www.coastergallery.com/1999/medusa10.jpg).

 

[Tarquin]

The speed of the lift hill doesn't determine the speed the car will travel on the track. Gravity and potential energy do, all the lift hill does is get it to the top of the hill. Think of Oblivion, if I speed up the lift hill, will the car drop quicker?

Launched coasters don't have lift hills such as the Incredible Hulk at IoA or Rita or Stealth, these are fired up the incline or along the track either by wheels or a cable at very high speed and therefore the start speed is based on the speed you are accelerated to by the launch, not the potential energy at the top of the drop.

So yes, you could replace the chain lift with a launch but then it is an entirely different type of coaster and it may affect the ride in other areas, such as needing more brakes or just being uncomfortable.

What I think people are referring to is the fact that if it starts off from the lift hill (down the first drop) at a higher speed than before, in theory it should be able to reach a higher speed at the bottom of the drop because it's starting at a faster speed already. Your comparison with Oblivion doesn't work because it doesn't go straight into a drop and in fact has a brake at the top to regulate the speed that the shuttles go into said drop.

I'm sure somebody will be able to explain it much better than I can though!

 

[Duffins]

They drop down to 3 ppl max when it rains on sonic already. So they already had some weather related procedures in place.

Not sure why the drop to 3 but it happens.

It's just the additional weight and the less effectiveness of the brakes in the wet, basically.

The changes they are having trouble making quickly are intriguing though.

Both Dragons Fury and Sonic Spin ball operate a lighter car weight in the wet due to the no braked block sections eg fury transfer track and station. Cars have "Slipped through" the transfer block and continued into the station (at a low speed) causing a system shutdown and ride evac and handing back over to engineering.

Also Fury has stalled previously between brake one and brake two.

I would presume that the changes being made are including updated cctv to fury as it is of poor quality and to the left of the operator and not directly in front. Makes it hard to use in real life unless in a shut down situation because the station is to the right

 

[Dave]

The speed of the lift hill doesn't determine the speed the car will travel on the track. Gravity and potential energy do, all the lift hill does is get it to the top of the hill. Think of Oblivion, if I speed up the lift hill, will the car drop quicker?

Launched coasters don't have lift hills such as the Incredible Hulk at IoA or Rita or Stealth, these are fired up the incline or along the track either by wheels or a cable at very high speed and therefore the start speed is based on the speed you are accelerated to by the launch, not the potential energy at the top of the drop.

So yes, you could replace the chain lift with a launch but then it is an entirely different type of coaster and it may affect the ride in other areas, such as needing more brakes or just being uncomfortable.

If you speed up the lift hill you are giving the train more potential energy, so it will progress around the track faster. But the difference will be small.

 

[Dave]

Towers was said to be very quiet yesterday. Well it looks like today is even more dead; the only attraction reporting a queue on ridetimes is Mr Bloom's Allotment (10 mins). Everything else is a 0 min wait.

It's not too quiet, Air & Octonauts is at 30min, Th13teen 25min, Nemesis 20.

For a Tuesday in term time it's a bit longer than you would expect actually but then factor in the closed rides and your probably looking at normal numbers

 

[Rob]

It does seem to have picked up since I initially checked which is good.

Numbers will be down for varying reasons but it doesn't look too bad. I suppose it does depend exactly how much throughputs are reduced with the new procedures.

 

[cotda]

The speed of the lift hill doesn't determine the speed the car will travel on the track. Gravity and potential energy do, all the lift hill does is get it to the top of the hill. Think of Oblivion, if I speed up the lift hill, will the car drop quicker?

Launched coasters don't have lift hills such as the Incredible Hulk at IoA or Rita or Stealth, these are fired up the incline or along the track either by wheels or a cable at very high speed and therefore the start speed is based on the speed you are accelerated to by the launch, not the potential energy at the top of the drop.

So yes, you could replace the chain lift with a launch but then it is an entirely different type of coaster and it may affect the ride in other areas, such as needing more brakes or just being uncomfortable.

Not quite true, in both cases (launched or not) you're true in stating the change in Kinetic Energy is (without taking friction/other energy wastage into account) equal to change in GPE, however the initial kinetic energy will also have an impact (up until terminal velocity)

0.5m(v^2 - u^2) = mgh
v^2 = u^2 +2gh

Oblivion is a special case as it is released over the hill after a stop, however smiler is provided with some KE by the lift.

 

[MichelinMan]

ADIPS safety test amusement rides, they are not part of the HSE but they work under their accreditation. All Rides get ADIPS check before their opened and annually.

Thanks for that Dave - didn't know who they were.

In that case, almost certainly the HSE wouldn't have known about any stalls during testing. Accreditation by the HSE purely means that the HSE has confirmed the capability of an organisation (in this case ADIPS) to carry out its functions. It wouldn't mean that the HSE gets to learn about anything they do, necessarily.

 

[John]

With the speed terms of the energy equation raised to the power of 2, the energy from the initial speed is usually almost insignificant. Increasing the speed of the lift hill by 5mph will increase the top speed slightly, but not by 5mph. The exact increase will depend on the previous top speed, with smaller increases on faster rides.

 

[stigzy]

I used to do that on roller coaster tycoon if my coaster didn't make it all the way around.

 

[EuroSatch]

The only way the car would be 'faster' from the drop is if it is accelerated over the edge, ie carries momentum over with it when released from the chain. Speeding the lift would not give it extra potential energy, which is based on the height of the drop only

 

[Dave]

The only way the car would be 'faster' from the drop is if it is accelerated over the edge, ie carries momentum over with it when released from the chain. Speeding the lift would not give it extra potential energy, which is based on the height of the drop only

If the chain is running faster then the car has more potential energy as it leaves the chain surely, but as John said it would be such a small difference in speed.

@John help us out here

 

[jon81uk]

If the chain is running faster then the car has more potential energy as it leaves the chain surely, but as John said it would be such a small difference in speed.

@John help us out here

The lifthill provides kinetic energy not potential energy.

I can't do the formulae as others can, but I think of it like a toy car on a slope. Push the toy car up the hill slightly quicker it will get to the top quicker, but it is gravity that will make it go down the hill the other side as the push just got it to the top. Add a launch mechanism and launch the car up a slope significantly quicker and the launch will propel the car up the slop and then down the hill faster.

 

[Dave]

The lifthill provides kinetic energy not potential energy.

I can't do the formulae as others can, but I think of it like a toy car on a slope. Push the toy car up the hill slightly quicker it will get to the top quicker, but it is gravity that will make it go down the hill the other side as the push just got it to the top. Add a launch mechanism and launch the car up a slope significantly quicker and the launch will propel the car up the slop and then down the hill faster.

that kinetic energy doesn't dissolve once you leave the chain though as you can't create or destroy energy, so what ever you call it if there is more kinetic energy from the chain the train will have more kinetic energy when it leaves the chain. So speed will be affected.

Just not by much as john says.

Your analogy would only work if you first stopped at the top of the slope, your not accounting for that kenetic energy from the chain and where it goes.

 

[EuroSatch]

Kinetic energy and potential energy interchange. The lift provides kinetic energy to 'do work', pushing the car to the top of the lift. At the top, all energy is potential, as it is essentially held there, and released under gravity. If the lift can provide enough energy so that it rolls over the crest of the hill of its own accord, then it was the potential energy of the drop height, plus the kinetic energy provided by the lift. This energy would be minuscule though, and would need to be pushed over with some force and make it over the hill with some speed to majorly impact on its maximum kinetic energy - and therefore maximum speed - at its lowest point on the track

 

[Slugjc]

I'm guessing Monday was down as people who may have to travel, cancelled so they didn't set off to find it closed. People would have got nervous if it was closed sat/sun and just not bothered. Way I see it

 

[Dave]

Kinetic energy and potential energy interchange. The lift provides kinetic energy to 'do work', pushing the car to the top of the lift. At the top, all energy is potential, as it is essentially held there, and released under gravity. If the lift can provide enough energy so that it rolls over the crest of the hill of its own accord, then it was the potential energy of the drop height, plus the kinetic energy provided by the lift. This energy would be minuscule though, and would need to be pushed over with some force and make it over the hill with some speed to majorly impact on its maximum kinetic energy - and therefore maximum speed - at its lowest point on the track

Yeah that's what I thought.

Physics lesson over.

 

[jon81uk]

Kinetic energy and potential energy interchange. The lift provides kinetic energy to 'do work', pushing the car to the top of the lift. At the top, all energy is potential, as it is essentially held there, and released under gravity. If the lift can provide enough energy so that it rolls over the crest of the hill of its own accord, then it was the potential energy of the drop height, plus the kinetic energy provided by the lift. This energy would be minuscule though, and would need to be pushed over with some force and make it over the hill with some speed to majorly impact on its maximum kinetic energy - and therefore maximum speed - at its lowest point on the track

Thats what I meant. and if the car is being pushed over with some speed (enough to impact on its kinetic energy as you say) then it becomes a launched coaster, not a lift hill really.

 

[delta79]

Then you would need to re profile the track to keep within g force limits

 

[Rob]

Either or, lift hill speed clearly has nothing to do with what happened and is extremely unlikely to provide any form of solution or mitigation.