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Coasters to Face G-Force Limits?
jonerik writes "NBC News is reporting that today New Jersey will begin examining the possibility of placing limits on roller coaster G-forces. Pointing out that the G-forces on coasters are considerably greater than even those experienced by astronauts and race car drivers, legislators on both the state and national levels want to start reining in coaster G-forces which have been blamed for a number of injuries and deaths over the past few years. Pansies. Why do they think people ride roller coasters to begin with?"
There are an aweful lot of roller coasters in New Jersey, and most aren't in big theme parks (like Six Flags and stuff).
Most are on the board walk on small piers, and there have been a number of deaths (actually, usually at least one every summer) from poorly design and/or maintained coasters. Regulating coasters is not necessarily a bad idea.
It makes sense to not allow high speed coasters on little piers that don't have enough staff to maintain it properly. I think that is the basis of a law like this.
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Space launches have steadily reduced their peak G forces over the years. During the Mercury and Gemini programs, the Astronauts were exposed to as much G force as modern jet fighters do in a dogfight, and for as long. The heavier Saturn launch system of Apollo was gentler, and the Space shuttle is very tame by comparison. Russian cosmonauts still get a better (in roler-coaster terms) ride than their American counterparts.
Given how tame the shuttle is, maybe it's technically true, if misleading, to say that roler coasters give the rider more G that an Astronaut experiences. (They did after all say "astronaut", not "cosmonaut") A space shuttle jockey, just barely goes over 3G. Some roler coasters may peak at 5. But here's the difference: The shuttle sustains the 3G for the entire duration of the post-SRB-separation boost. That's several minutes of continuous burn. I doubt whether any roler coaster ever peaks over 3G for more than 2 or 3 seconds at a time, if that.
The physiological risks associated with high G are not determined by the magnitude of the G alone, but mainly by other factors:
The duration that high G is sustained. Long duration deprives the brain of blood long enough to cause very bad things to happen. No real risk there on roler coasters.
The onset-rate. How suddenly the G force starts and stops. High onset rates cause all kinds of problems, including back and neck problems, inner ear problems, and even brain dammage in extreme cases. Once again, no issue in a well-designed roler coaster.
Head movement. High G forces, especially combined with high onset rates, are aggrivated by sudden head rotation. This can be a problem even if the G forces are only momentary. Inner ear problems can result. Roller-coaster designers have little control over this factor, so perhaps it is a real concern.
Negative G. (Negative means the blood rushes to your head). High negative G can cause all kinds of problems, including burst blood vessels in the eyes. I've personally never heard of a roler coaster that goes beyond about -0.5G or so, and even then for less than a second, so I doubt that this is an issue.
Sudden transitions from positive to negative, or vice-verca. All the bad things associated with high positive G are accentuated if it immediately follows a period of negative. And vice verca if negative follows a period of positive. This will become a real issue if roler coasters ever start exploring the negative regime. Frankly, I doubt that they will. The average rider views positive G's as exhilirating fun, but would find negative to be obnoxious and uncomfortable.
Frankly, I'm much more worried about the structural design and maintenence of the coaster than the G-profile. But then, I've flown to WAY higher positive and negative G forces than either roler coaster or space shuttle experience, and I know the breathing techniques, and I know to keep my head relatively still. Roler coasters all seem really disappointing to me.
I do know that I blacked out for a few seconds while riding Nitro in Six Flags / New Jersey. It was right at the top of a peak and I imagine the coaster was pulling some serious negative G's.
Anyway...I remember my vision starting to darken and then go black....and returning a few seconds later. I'm a young adult, in fairly good shape and could see how this could become a serious problem for other riders.
Remember....think back to early Coney Island when there were very few safety regulations, and injury was more the norm then the exception.
-Chris
--an unbreakable toy is useful for breaking other toys--
Which indicates that you shouldn't be driving.
There's this concept of keeping enough distance between you and the car in front so that if they slam on their brakes you have time to slam on yours - without being even close to hitting them.
Only an idiot who drives way to close would manage to come close to crashing in those circumstances, let alone do so five times.
What happens when the car in front sees some kid step out from between parked cars and you don't because from your viewpoint they are obscured by something? Do you almost have an accident because the other driver slams on their brakes?
Braking hard is dangerous (especially if the guy behind you is changing radio stations at the time) but sometimes you need to. Hence you should always leave enough room and assume the other driver just might need to (or maybe the other driver is an idiot who will slam on his brakes because he missed his turn off)...
Kids have underdeveloped peripheral vision, they are bad at judging speeds and distances of object moving at the speeds cars go, they are easily distracted, and often do not notice what is happening around them when focused on something (like getting their ball that just bounced onto the road, or seeing their mother who is an idiot and is on the other side of the road). All this means they will run onto roads...
Stopping for buses to (un)load seems silly to me, a slow speed limit when the bus is (un)loading seems better.
Trend? I see incomplete data. Also a self-fulfilling prophecy. Where are statistics about ridership versus injuries?
"If a drug caused 58 cases of brain damage, it would be pulled!" Do some research. Do you know how many thousands of deaths each year are attributed to very popular FDA approved OVER THE COUNTER drugs? Do Tylenol and Asprin ring a bell?
Why don't you work on banning alcohol which causes orders of magnitude more deaths and permanent injuries than something as insignificant as roller coaster.
Don't you understand that we have much greater problems to worry about in this country and regulating roller coasters is not the best place to spend our tax dollars right now?
Today in terms of safety expenditures, we spend $0.0021 per mile for airlines, $0.00015 per mile for automobiles. If we spend $0.00015 per mile on roller coasters we would only be spending $75,000 per year. In 1997 there were 21920 auto fatalities, 3 roller coaster fatalities.
No, that's not their job. But sometimes they think it is, and that is pretty god-damned unfortunate.
Trenton, N.J. - A New Jersey judge today declared that it would be illegal to expose citizens to gravitational fields greater than 0.2 G . "Every year more people are falling or jumping to their deaths," explained Justice Iverson, " a situation that cannot be allowed to continue. Every day on television I see coyotes cruelly crushed by falling anvils, and its time something was done. I am issuing an extradition writ for a Mr Isaac Newton who I believe is responsible for the problem."
Cynics have suggested that Iverson is merely trying to improve his golf game. Since the ruling, he has been regularly driving the greens at exclusive Rolling Hills Country Club - with his sand wedge. Justice Iverson is aged 92.
In related news, senior mafia officials pledged to 'eradicate chance' from casinos across the USA.
Not to have their bodies exposed to more forces and danger than most astronauts ever experience
From the original post:
the G-forces on coasters are considerably greater than even those experienced by astronauts and race car drivers...
I flew military jets for 9 years, and I think these comparisons are crap. When people used to ask me how jets compared to roller coasters, I would tell them that the two experiences are totally different. It's a matter of scale. Sustaining 4G or more for even 10 seconds, let alone 30 or 60 seconds or more, is an experience that simply cannot be reproduced by any rollercoaster that can fit in a theme park. The effects of the sustained G are DRAMATICALLY different than the one or two second hits (or three or four...whatever) felt on a high performance rollercoaster.
I recently road with my brother on a rollercoaster that I considered to be quite exciting, with corkscrews and consecutive loops, and when it was over he asked me how many G's he thought we had pulled. Based on the sensations I had felt (compared to my years in jets) I guessed 1.5-2. I was surprised to see a brochure later that claimed the ride pulled 6G. The two or three second hits just didn't have time to register.
Another example: a person using an ejection seat pulls an ongodly amount of G -- something like 30 or 60, although the actual number escapes me. Obviously this is enough to kill a man, but the brief time period involved make it survivable. I've known people who ejected and were able to walk around with no problem immediately afterward.
The point is that comparisons to astronauts and race car drivers is misleading. The maximum G must be examined only in conjunction with the period of time over which the G occurs. Brief hits DO NOT COMPARE to sustained G. Maybe rides should be limited and maybe they shouldn't, but the forces faced by astronauts are not part of the debate.
Evil is the money of root.