 Poster: A snowHead
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The victim was doing speed only experienced skiers can managed. He appeared to ski on one leg with the other in the air when reaching the middle of the piste. When going over the border he was threw into the air before hitting the tree. All the skiers in the video seemed to be racing with each other. By any standard the skiers were really flying in video.
The Sugarbush people reported that the accident took place in the Sleeper Run which is a blue run no where near the bottom of the Gate House Express Quad chairlift in North Lynx Peak. From memory the blue run, called LWR Hot Shot, underneath the chairlift is quite flat and undulating.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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| Bode Swiller wrote: |
15mph, the speed at which it is generally accepted that a helmet makes no difference |
That is taken seriously out of context IMO. I worked in F1 for over 10 years and in that time I saw some serious crashes at a tad over 15 mph with the car stopping in a matter of a few feet, with drivers sustaining instantaneous peak decel of 30G or more without significant injury. It's quite complex when you get into the details, but there are a lot of factors that determine whether or not a particular combination of speed, impact and deceleration will be fatal regardless of what physical head protection you happen to have. Try googling the "Gee Whiz" human rocket sled tests if you want to see what kind of linear deceleration a human can really survive (600-0 mph in just over 1 sec)
I have no doubt that a 15+ mph direct head-butt impact with a solid tree may well prove to be fatal with or without a helmet due to the blunt force trauma alone, but that certainly doesn't mean that any abrupt crash above 15 mph will automatically kill you simply from the deceleration alone or that a helmet won't mitigate your head injuries to some extent. The deceleration involved in a typical recreational skiing crash is really the least of your worries. At those speeds it's only the direct impact damage that would be of major concern.
I'm not saying you should wear a helmet, but it's frankly ridiculous to suggest that if you ski above 15 mph then a helmet is pointless. While it probably wouldn't save you from a direct straight on head-tree impact at 15+ mph it would help to some extent in most of the other countless ways you could bang your head during a high speed ski crash.
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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| uktrailmonster wrote: |
| Bode Swiller wrote: |
15mph, the speed at which it is generally accepted that a helmet makes no difference |
That is taken seriously out of context IMO. I worked in F1 for over 10 years and in that time I saw some serious crashes at a tad over 15 mph with the car stopping in a matter of a few feet, with drivers sustaining instantaneous peak decel of 30G or more without significant injury. It's quite complex when you get into the details, but there are a lot of factors that determine whether or not a particular combination of speed, impact and deceleration will be fatal regardless of what physical head protection you happen to have. Try googling the "Gee Whiz" human rocket sled tests if you want to see what kind of linear deceleration a human can really survive (600-0 mph in just over 1 sec)
I have no doubt that a 15+ mph direct head-butt impact with a solid tree may well prove to be fatal with or without a helmet due to the blunt force trauma alone, but that certainly doesn't mean that any abrupt crash above 15 mph will automatically kill you simply from the deceleration alone or that a helmet won't mitigate your head injuries to some extent. The deceleration involved in a typical recreational skiing crash is really the least of your worries. At those speeds it's only the direct impact damage that would be of major concern.
I'm not saying you should wear a helmet, but it's frankly ridiculous to suggest that if you ski above 15 mph then a helmet is pointless. While it probably wouldn't save you from a direct straight on head-tree impact at 15+ mph it would help to some extent in most of the other countless ways you could bang your head during a high speed ski crash. |
No one has said that.
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^^^ +1
To clarify, if a skier with helmet skis head first into a tree at 15mph, and another without a helmet does the same, it is generally accepted by those who study this kind of thing, that the outcome will likely be the same.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| Bode Swiller wrote: |
8611, watch that vid in the opening post. They are.
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That's what I mean, they seem to be absolutely flying along, and the slope seems next to flat! Its the kind of slope that you'd ski fairly slowly down to the next lift, a slope thats getting you to other slopes rather than a slope in itself.
I was skiing twice in the last month, usually when I'm on lifts I look down and watch for good skiers and try and think how they're doing it and apply it on the next run. When I watched the vid it immediately occurred to me that the skiers were going much faster than the ones I had been watching recently. Its actually hard to build up that kind of speed on a slope like that.
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| 8611 wrote: |
| Bode Swiller wrote: |
8611, watch that vid in the opening post. They are.
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That's what I mean, they seem to be absolutely flying along, and the slope seems next to flat! Its the kind of slope that you'd ski fairly slowly down to the next lift, a slope thats getting you to other slopes rather than a slope in itself.
I was skiing twice in the last month, usually when I'm on lifts I look down and watch for good skiers and try and think how they're doing it and apply it on the next run. When I watched the vid it immediately occurred to me that the skiers were going much faster than the ones I had been watching recently. Its actually hard to build up that kind of speed on a slope like that. |
The slope is hard packed so the skis will run. Also, the speed of the chair makes the skiers look a bit faster.
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| stuarth wrote: |
Not really any clutching going on, just a bit of physics. That is exactly the point, the deformable liner of a helmet ensures your head doesn't go from 25 to 0 in 0.00 seconds, it slows down that deccelaration. It also spreads the load so you are less likely to crack your skull. I'll dig out a picture of the remains of my friends helmet and you can see how destruction of a helmet helps (it takes energy to do that damage) - this is also why cars are a bit squishy in the right places
I'm not really trying to promote the use of helmets or not, personally I've dented two into submission, and also seen (and heard!) someone I was skiing with hit a tree at pretty high speed with one on, so I'll keep using my mightily expensive one. The only two people who I'll insist have to wear one are my son and I.
But do agree that if you hit an immovable object hard enough you are in big trouble whatever, so the best thing is not to. |
You should look at the physics a bit more carefully, yes a ski helmet does slow things down a bit but not very much and more to the point not enough to prevent serious injury or death in a situation where that would have been the case without a helmet. They are bump hats, nothing more and the standards they are made to support this. They will stop superficial injuries like bruising and cuts but won't do squat for crashes that would have resulted in serious trauma to your brain anyway. Compare one side by side to a motorcycle helmet for example to see the difference.
I'm not trying to dispute their utility but people need to be realistic about the level of protection you actually get from one.
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So we've descended into another farcical helmet squabble. Helmet wearing/not helmet wearing is all fine by me but I don't think we need the evangelists on both sides attributing arguments that the other side isn't even offering. I'm pretty sure even the most ardent helmet fan doesn't claim it's a universal forcefield nor does the non helmet wearer recklessly jeopardise their family's future should they dare step on a slope without one.
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You'll get to see more forums and be part of the best ski club on the net.
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| Quote: |
I'm pretty sure even the most ardent helmet fan doesn't claim it's a universal forcefield
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fatbob, generally true, but then you get some who say:
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| I'm not really trying to promote the use of helmets or not, personally I've dented two into submission, and also seen (and heard!) someone I was skiing with hit a tree at pretty high speed with one on, so I'll keep using my mightily expensive one. |
Still staggers me that people boast about the number of blows to the head they've had. It just means they are a danger to themselves and probably others.
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I am not a great fan of helmets see previous threads ad nauseam. But I don't see why the assumption is always that all crashes involve an instantaneous change inthe speed ones head is travelling to zero. The majority of crashes that I have witnessed seem to involve glancing blows etc.
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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| Bode Swiller wrote: |
| Quote: |
I'm pretty sure even the most ardent helmet fan doesn't claim it's a universal forcefield
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fatbob, generally true, but then you get some who say:
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| I'm not really trying to promote the use of helmets or not, personally I've dented two into submission, and also seen (and heard!) someone I was skiing with hit a tree at pretty high speed with one on, so I'll keep using my mightily expensive one. |
Still staggers me that people boast about the number of blows to the head they've had. It just means they are a danger to themselves and probably others. |
I personally don't see how that's boasting... He merely stated he'd bumped him helmet, no hint of arrogance either...
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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| PJSki wrote: |
| stuarth wrote: |
| Bode Swiller wrote: |
| stuarth wrote: |
Bode Swiller,
Well I guess it slows down and disipates the force transfer with the energy absorbed, spread out and disipated by the helmet, giving your brains natural helmet a bit more of a fighting chance. |
Maybe clutching at straws there. If your head goes from say 25mph down to 0 mph in 0.00 seconds you're in trouble either way. It's bad enough when you walk into a door at 2mph. |
Not really any clutching going on, just a bit of physics. That is exactly the point, the deformable liner of a helmet ensures your head doesn't go from 25 to 0 in 0.00 seconds, it slows down that deccelaration. |
25mph is too fast to survive even with a helmet. Helmets are only rated to 15mph. |
Someone should tell Downhill racers not to bother with the helmets then.......
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T Bar, that's not the assumption though. This came up again in part because people, myself included, complained that the video of the injured snowboarder misrepresents what ski helmets are capable of. From the injuries the guy sustained you can see quite simply that wearing a helmet would have made no difference in that case, yet the video and other people blithely assume it would. I actually think helmet wearing is pretty sensible since the majority of the time you aren't going to be hitting your head into anything hard enough to cause serious injury and the kinds of things the helmet would protect you make it useful. I just dislike the agitprop in the media and films like the one on the first page which oversell the capabilities of helmets.
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You know it makes sense.
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| tomb wrote: |
| Bode Swiller wrote: |
| Quote: |
I'm pretty sure even the most ardent helmet fan doesn't claim it's a universal forcefield
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fatbob, generally true, but then you get some who say:
| Quote: |
| I'm not really trying to promote the use of helmets or not, personally I've dented two into submission, and also seen (and heard!) someone I was skiing with hit a tree at pretty high speed with one on, so I'll keep using my mightily expensive one. |
Still staggers me that people boast about the number of blows to the head they've had. It just means they are a danger to themselves and probably others. |
I personally don't see how that's boasting... He merely stated he'd bumped him helmet, no hint of arrogance either... |
I think
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| personally I've dented two into submission |
is most definitely boastful. Hey, it's his head, so you might ask why care. Thing is, anyone who is regularly out of control enough to dent two helmets into submission, is probably the same kind of lump that will smash into your kid.
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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meh, Fair enough, I slightly jumped the thread midstream and read stuff about helmets not saving you in massive decelerations.
I wear a helmet but only out of social propriety/ family pressure. Bit of a sceptic, though last week it was helpful in the cold temperatures.
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Poster: A snowHead
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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Bode Swiller
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According to American research I've seen that I don't think is available on the web (Carl Ettlinger and others), average speed on a groomed blue run is nearly 27mph. Helmeted skiers go faster on average by 3mph, snowboarders and females slower. Fastest are helmeted male skiers, who are also heavier and have higher kinetic energy. A helmet is made to withstand a 14mph hit. Research on brain damage reckons the deceleration on the brain of a 12mph hit is enough to cause serious brain damage.
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I don't have any bother with a piste user putting a lid on but I do object to the wearer going faster just because of having the lid on. These piste users keep themselves a bit safer but could increase the risk to others.
It is the same thing in motorcycling. Before the helmet was mandatory bikers would claim doing a ton (100 mph) as it was a big deal because tears would come out at such a speed. Now with a full face helmet even a learner biker can do 180mph and would not feel a thing on a modern bike complete with flaring.
Last edited by Obviously A snowHead isn't a real person on Wed 8-02-12 12:27; edited 1 time in total
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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James the Last,
Yep, good in winter a bit of a pain in spring and a menace if going uphill.
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You need to Login to know who's really who.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| saikee wrote: |
Bode Swiller
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According to American research I've seen that I don't think is available on the web (Carl Ettlinger and others), average speed on a groomed blue run is nearly 27mph. Helmeted skiers go faster on average by 3mph, snowboarders and females slower. Fastest are helmeted male skiers, who are also heavier and have higher kinetic energy. A helmet is made to withstand a 14mph hit. Research on brain damage reckons the deceleration on the brain of a 12mph hit is enough to cause serious brain damage.
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I don't have any bother with a piste user putting a lid on but I do object to the wearer going faster just because of having the lid on. These piste users keep themselves a bit safer but could increase the risk to others.
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A bit sceptical about the claimed speeds but as far as going faster, it could be that faster skiers wear helmets rather than wearing helmets cause skiers to go faster.
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T Bar, they took 650 readings across 3 resorts - one in Utah, one in New York State and one in Vermont. They chose only groomed blue runs and didn't radar resort workers, kids or people in lessons. The speeds recorded were the highest speed reached by the skier/boarder while under observation. I can well believe those averages. To put it in perspective Usain Bolt reaches a max speed of 24mph in the 100m and most would expect to ski around that speed or faster.
16% of those observed were in excess of 33mph.
"Most catastrophic and fatal injuries, occur to experienced males on groomed 'blue square' trails; usually head injuries due to high speed collisions with trees." That's what they conclude, and note that's for the USA.
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Tirol, good point. Would any of the H&S experts on this thread care to comment about why downhill racers bother with helmets?
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You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
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Dr John, not just helmets, they are even talking about introducing an airbag system for racers. Being developed now.
Of course they need head protection. If they fall they get captured by safety netting or they slide a long way and sometimes they run straight into hard plastic gate markers.
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Bode Swiller, far more skier and boarders on a public slope than gate markers on a race course, and skiers/boarders tend to move quicker than gate markers. For that reason (in addition to my own clumsiness) I wear a helmet.
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snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
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I have worked out from information in this thread, that if Usain Bolt were to fall over while running in his race HE WOULD DIE even if he was to be wearing a helmet. Wow!
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And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
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Chris Bish, Only if he hit a solid post at full speed.
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they are even talking about introducing an airbag system for racers
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already happening with horse jumping and 3 day eventing I think
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You know it makes sense.
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Dr John, it's all a bit asinine, downhill racers would and do die from brain injury despite wearing helmets (e.g. Régine Cavagnoud). Part of the reason for padding and netting is to avoid them being exposed to hitting anything, even then people have died from injuries sustained crashing into the netting. Helmets are worn because they don't typically fall on their heads because they offer protection for the sorts of forces involved in glancing blows and the like which is where they are useful. The point being don't expect too much from safety equipment.
Chris Bish, if he was able to transfer all the force of his forward momentum right into his head he maybe could. 
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Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
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| Dr John wrote: |
| Bode Swiller, far more skier and boarders on a public slope than gate markers on a race course, and skiers/boarders tend to move quicker than gate markers. For that reason (in addition to my own clumsiness) I wear a helmet. |
I think that's a brilliant idea; use humans (preferably small children) as gate markers, and give 'em GoPros to capture the action.
Now, if you recognise that you are clumsy, then really you need to wear a helmet that has lots of padding on the outside too. Sounds like you are likely to crash into me so I think that would be a public-spirited precaution to take.
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Poster: A snowHead
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| PJSki wrote: |
No one has said that. |
| Bode Swiller wrote: |
Just about ALL who ski/board on such groomers travel at speeds way above 15mph, the speed at which it is generally accepted that a helmet makes no difference, so this, for certain, is where technique/mountaincraft debate should start and helmet debate should end.
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Well he said this ^, which to me anyway implies it.
From his other posts I can also see that he doesn't really understand the very different effects you get from pure deceleration and a blunt impact trauma. The human body can actually cope with much higher peak deceleration than was thought possible until fairly recently. The instantaneous G threshold where you are likely to suffer long term head injury (eg. detached retinas) is around 50G and you can comfortably deal with around 25G and walk away. Putting this into real numbers, if your head decelerated from 15 mph to zero in 0.05 of a second you would only experience around 14G from the pure deceleration and you would be perfectly fine providing there was no direct head impact involved - it's a fairly common misconception that your brain would be squidged into mash by such a sudden deceleration. The only thing that you have to worry about at these tame speeds is if your head or other critical parts of your body suffer a direct impact force. Then it would be the pressure resulting from the impact force that would injure or kill you, not the deceleration. It's a subtle difference but very important to understand when analysing crashes. A helmet will significantly reduce the pressure acting on your skull in any force impact even if it doesn't have any significant effect on the deceleration of your head. The deceleration element is basically totally irrelevant in any relatively slow speed accident.
So just to be clear on this, just because you are skiing above 15 mph, it doesn't mean that you will die in any sudden-stop type of accident unless you are unlucky enough that the entire brunt of the impact that stopped you is taken directly on your head. The sudden deceleration itself will not be an issue, only the damage from direct force impact on whatever parts of you actually hit the tree. So you could break your leg, ribs, smash your head or whatever else. But as long as the direct head-on impact with your head is less than 15 mph a helmet will certainly be of some benefit in dissipating the resultant impact force.
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Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
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I wear a helemt because it keeps my ears warm. It also has a dent in it from an over enthusiastic French bloke pulling down the safety bar!
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Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
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Dr John,
As many have said a highish speed direct impact with an imovable object resulting in a dead stop is likely to cause death (the mechanics of this could be head injury or any number of the other vital bits floating around inside us getting squished).
The majority of impacts occur as a result of falls rather than crashes.
In this case the only deceleration we are interested in is the downwards decel of the head hitting the snow/ice and the velocity (simplisticly) is a result of the height from which your head falls from (ignore the forward velocity as the majority of that is maintained and hence has much lower decel). For this reason the majority of impacts to the head caused by skiing come under the 15 MPH limit mentioned and the helme is of use.
This changes if we catch an edge and face plant or tumble when a greater part of the forward velocity is converted in to velocity towards the piste (downwards) in this case we are more likely to find our head impacting at the piste with a force likely to cause death or serious injury.
Typically DH racers dont suffer the crash type impact due to the presence of safety netting etc. The worst injuries in down hill racers seem to occur when they have gone over a jump and lose it resulting in a fall impact from a great height or when they start rag dolling and spinning converting the forward velocity in to velocity towards the snow. In these situations their helmets (probably worth several £k rated to way more than 15mph) almost certainly save their lives.
The above is based on my knowledge of Physics rather than any health and safety or industry experience.
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You need to Login to know who's really who.
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uktrailmonster, just a reminder, this thread is about a guy skiing head long into a tree.
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Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
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| Bambi on ice wrote: |
Dr John,
As many have said a highish speed direct impact with an imovable object resulting in a dead stop is likely to cause death (the mechanics of this could be head injury or any number of the other vital bits floating around inside us getting squished).
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To be correct it's really only the direct impact forces that are dangerous at the recreational skiing speeds we are talking about here. The pure deceleration from the dead-stop is not really an issue in itself at these speeds (see my last post above for explanation). Deceleration itself and resultant squishing of internal organs only becomes a real issue in very high speed crashes eg. aircraft, motorsport etc.
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You'll need to Register first of course.
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| Bode Swiller wrote: |
| uktrailmonster, just a reminder, this thread is about a guy skiing head long into a tree. |
Of course and I think the outcome of that is pretty obvious, but as you wrote a load of quite misleading and factually incorrect stuff about the effects of deceleration in a crash I thought it would be useful to comment. Of course you can feel free to disagree if you think you know better.
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This thread reports some 18 deaths this year.
Apparently almost all wearing helmets (as the poster has an interest in them).
All except one deaths were in USA resorts. The exception was a 6 years child taken to 2900m in Saas Fee in Switzerland by an instructor and buied in an avalanche. The instructor survived.
Tree has played a significant part in these deaths. Some fatalies occured in backcountry skiing.
We all know skiing among trees are not common in Europe but popular in the American resorts.
Helmet is a strange thing. I found myself, wearing a Gortex hat, in small minority when I ski Adelboden and Gstaad in Switzerland. Yet in the same week later in Monte Rosa, Pila, Cervinia, Zermatt and Saas Fee the piste users without a helmet were in the big majority.
Last edited by Then you can post your own questions or snow reports... on Wed 8-02-12 15:06; edited 1 time in total
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Good grief. Somebody died in a accident enjoying a sport/hobby which is universally accepted to have some element of danger. People also die from falling down the stairs, eating too much fatty food, smoking, crashing a vehicle, catching a virus, etc. Life is full of risks. We choose which risks we are prepared to take and we deal with the consequences. Personally I'd much rather die from head butting a tree on a ski slope than a slow painful miserable death from cancer, but I expect the latter is far more likely for many of us.
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You'll get to see more forums and be part of the best ski club on the net.
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saikee, I suspect your regular common or garden European heart attacks etc don't get reported by resorts. Plenty of avy deaths in Europe every year too.
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uktrailmonster,
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To be correct it's really only the direct impact forces that are dangerous at the recreational skiing speeds we are talking about here. The pure deceleration from the dead-stop is not really an issue in itself at these speeds (see my last post above for explanation). Deceleration itself and resultant squishing of internal organs only becomes a real issue in very high speed crashes eg. aircraft, motorsport etc.
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Appologies for being a pedant but the deceleration is what causes the force... Force = mass x acceleration... so we are talking about one and the same thing!
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FAQ
