G's

Do other countries have looser standards when it comes to g force? I was watching a video of Boldar and it was wicked

I don't believe anywhere in the US have limits except New Jersey, and they are extremely loose limits that no coaster has ever exceeded.

Many people don't fully understand how it all works. Very few realize that for example WildCat at Cedar Point pulls more g's than Millennium Force.

What's Boldar? ;)

Probably http://rcdb.com/ig1562.htm

jwhoogs, where did you see the video, send me a private message if you can. That ride looks completely insane.

gomez, where does Wildcat reach more g's than that MF? The first drop and first turn pulls some mean g forces that a lot of people grey out from.

Well, not knowing exact numbers, if gomez's statement is true, its because of the impulse of the g's. Say MF pulls x amount of g's over a certain time. The reason people grey out is because the g's are sustained over a larger amount of time relative to Wildcat, which can pull x+1 amount of g's over a very short time span, so you don't even feel it. Another example would be when you sneeze, you pull something 18 g's on your body. That number may be slightly off, but you get the idea.

Makes sense.

Anyone ever ride the Mighty Lightnin' at Lake Winnie!? I love the park, a dream come true for a classic park lover. But that L&T System built wild mouse has a last curve that I think could probably permanently hurt someone.

Just as much if not more than a ride on the pre-2007(2006?) Son Of Beast.

That last curve has a whiplash ("jerk" - a change in acceleration, physically) moment. It's scary.

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gomez said:
Many people don't fully understand how it all works. Very few realize that for example WildCat at Cedar Point pulls more g's than Millennium Force.

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I know quite a good amount about gravitation forces, and I'm going to have to remain skeptical about your claims.

I think what gomez is trying to point out the height and speed of a roller coaster have little to do with the acceleration the rider feels. It's like driving a car. Just because you're going fast on the freeway doesn't mean you feel more lateral forces when turning because the turns will be designed differently (more stretched out) compared to a sharp 15mph turn on a country road.

It's the same idea that Thriller, a coaster that's 113ft tall can pull +6.5Gs, while at 260ft Fujiyama only pulls a max of +3.5Gs.

If anyone is interested I saw the video on you tube. Find the correct spelling which I didn't do and type it in.

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PKevin2004 said:
I know quite a good amount about mechanical engineering, and I'm going to have to back Gomez up.

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I'm not saying it isn't true, I'd just like to see some actual numbers. I've ridden both many times and never thought Wildcat was that forceful no matter how short the period of force is.

The current industry standard (which is the law in some jurisdictions) is ASTM F 2291-06a.

ASTM F 2291-06a:7 establishes limits for accelerations as measured in accordance with ASTM F 2137 and filtered at 5 Hz. Rides can be designed to provide accelerations outside the limits specified in 2291-06a:7 provided that justification is given via a review by a biodynamic expert. Limits specified in F 2291-06a apply only to sustained accelerations lasting longer than 200 milliseconds (0.2 seconds) and to riders who are at least 48" tall.

The actual limits are specified in F 2291-06a:7 by means of Figures 6-20, and are actually quite complicated, taking into consideration the orientation of the rider, the direction, magnitude, and time limit for the acceleration, and also gives some guidance on reversals.

The nature of the ASTM license and the complexity of the material precludes me from posting details here, but there's enough information there that you can look it up. The diagrams are very similar to (possibly identical to) those used in the New Jersey statute.

Does that answer your question? 8-)

BTW: Physics-day experiments involving homemade mass-spring accelerometers have revealed that indeed, Wildcat produces higher forces than Millennium Force. A group of students proclaimed to me that they had measured +6G on Wildcat. I don't know if I believe that, but I can believe that Wildcat generates higher forces than Millennium Force.

--Dave Althoff, Jr.
Member, ASTM Committee F-24 on Amusement Rides and Devices

*** Edited 4/3/2008 6:06:10 PM UTC by RideMan***

^Uh... yeah, that's it... ;)