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yobnoc

Full-face helmets

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(edited)
20 hours ago, meat.missile said:

 If your reading comprehension was better (possibly English isn't your first language) you would understand that I said it is negligible when compared to an impact rated helmet. I can tell that you don't care about about protecting your brain. You care about bumps and scrapes which a non-impact rated helmet is handle well. When it comes to preventing damage to the brain caused by blunt impact like a baseball bat, the ground, or another skydiver, a non-impact rated helmet is not going to substantially limit the amount of force transferred to the brain

  

I understood quite clearly what you said, perhaps negligible does not mean what you think it does. 

negligible: so small or unimportant as to be not worth considering; insignificant.

If I was going to take a low turn into the ground or smash into a guy who corked out of a sit, I'll take my G3 over nothing. Therefore, it is not "negligible" compared to an impact rated helmet. It provides less protection than an impact rated helmet for sure, but its better than nothing. This is not hard to understand.

Edited by VTmotoMike08

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(edited)
6 hours ago, VTmotoMike08 said:

I understood quite clearly what you said, perhaps negligible does not mean what you think it does. 

negligible: so small or unimportant as to be not worth considering; insignificant.

If I was going to take a low turn into the ground or smash into a guy who corked out of a sit, I'll take my G3 over nothing. Therefore, it is not "negligible" compared to an impact rated helmet. It provides less protection than an impact rated helmet for sure, but its better than nothing. This is not hard to understand.

It isn't hard to understand, which is why your contradictory statements are entertaining.

Anyway, for everyone else. Drilling the shell of the G4 voids the warranty from Cookie. When it comes to impact rating, the G4 will lessen the severity of trauma to your brain during an impact. This could prevent a concussion being elevated to a TBI or worse.  When compared to the G4, the G3 does not have impact dampening foam and while it may prevent cuts and scrapes it will not do much, if anything to prevent brain injuries. 

Edit: Since it seems you have a rudimentary understanding of this topic, here is a brief explanation of this helmet impact rating. 

EN 966

Shock Absorption

"Where helmets are intended to provide protection for the users’ head in the case where the user themselves provide the movement, or where the user is likely to come under impact from items other than from above, helmets are usually tested using the falling headform method. Instead of using a fixed headform impacted with a falling mass, the headform itself, with the helmet fitted, is raised above a fixed anvil and dropped to generate the impact. Headforms, which are typically made from aluminium alloy, are made in several sizes so as to allow a reasonable fit to the helmet, and contain a tri-axial accelerometer (three single accelerometers in the x, y and z planes). On impact, these accelerometers will record the acceleration (or in this case, deceleration) of the headform in all three directions, and record a resultant value. In addition, the acceleration plotted over time can be used to calculate the head injury criterion (HIC), which gives a measure of the expected likelihood of serious injury to the user. It is calculated based on an integration of the acceleration against time between two points on in time.

Helmets can be dropped onto different types of anvil, including flat, kerbstone (corner) and specific-shaped anvils, such as balls. Drop heights will vary from each standard, depending on the perceived hazards in use. In the case of helmets for airborne sports, the headform is dropped from a height of approximately 1.5m (up to 89J) onto both flat and kerb anvils, with a maximum allowable acceleration of 250g (2453m/s2). Testing is carried out following conditioning to high temperature, low temperature or UV ageing."

 

 

 

 

Edited by meat.missile

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(edited)

I'm looking for used G3.  Not impact rated.  You should be definitely upgrading to a G4 for your safety.  :)  Think of getting 30% off your new G4 by trading in your G3 to me!  (I'm going to likely want about 6 of these to fit different sized heads for a school that's not for skydiving).  I figure it's a good way to put your G3 to good use (for someone who almost could use a bike helmet, but needs the face shield and chin guard) and get a 30% discount!  (or if anyone knows a school that will be upgrading and getting rid of a pile of full-face helmets, please let me know).

 

Edited by Hobbit44

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(edited)
3 hours ago, sundevil777 said:

Without test data to compare the performance of a G3 vs G4 vs no helmet at all, we are speculating on how negligible the impact protection of a G3 or any other helmet is. Maybe we already have the data to make that comparison?

It isn't really speculation, it's physics. 

 

 

Edited by meat.missile

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17 hours ago, sundevil777 said:

There is no misunderstanding of how helmets work.

The point I would make is that without data, we don't know if the liner for a G3 is 0.1% or 1% or 10% as effective as the shock absorbing material used in a G4.

You don't need a number to know it wont do anything meaningful. 

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(edited)

This is a ridiculous argument. You are spreading bad, potentially life threatening information.

If you take speculating to mean, my education in mechanical engineering and studies on how helmet design and padding effect the amount of energy transferred to the brain, then yeah, I'm speculating. Or maybe it is my educated, informed, and professional opinion.

But sure, don't listen to me, leave the prevention of brain damage up to some thin foam. 

 

Edited by meat.missile

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1 hour ago, meat.missile said:

This is a ridiculous argument. You are spreading bad, potentially life threatening information.

If you take speculating to mean, my education in mechanical engineering and studies on how helmet design and padding effect the amount of energy transferred to the brain, then yeah, I'm speculating. Or maybe it is my educated, informed, and professional opinion.

But sure, don't listen to me, leave the prevention of brain damage up to some thin foam. 

 

I also have a mech eng degree. I haven’t spread any bad, life threatening info. Please take it easy, I didn’t think curiosity would evoke such a reaction. Someone might actually know the answer to how well the old vs new helmet compares. It definitely will be better than nothing. 

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(edited)
8 hours ago, sundevil777 said:

I also have a mech eng degree. I haven’t spread any bad, life threatening info. Please take it easy, I didn’t think curiosity would evoke such a reaction. Someone might actually know the answer to how well the old vs new helmet compares. It definitely will be better than nothing. 

Edit: I decided what I said was hash. 

Long story short, The G3 is not going to protect your brain from smashing into the side of your skull. 

Edited by meat.missile
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2 hours ago, meat.missile said:

Edit: I decided what I said was hash. 

Long story short, The G3 is not going to protect your brain from smashing into the side of your skull. 

Based on what? Tests? Calculations? You are just guessing and speculating. 

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(edited)

BTW I had some intimate contact with the wall of several windtunnels, wearing a G3 and I am 100% certain  it would have hurt a lot more without a helmet. So in my opinion, your claim that a G3 or any helmet without certification  gives no (or negligable) protection is nothing but bs.

Certification is nice, it tells me that a certain level of safety is guaranteed. But it does not mean that the reverse is also true, that a non-certified helmet has to be inferior. It just might be. 

 

Edited by evh

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(edited)
9 hours ago, evh said:

Based on what? Tests? Calculations? You are just guessing and speculating. 

I went over this like, 2 posts ago. 

 

9 hours ago, evh said:

BTW I had some intimate contact with the wall of several windtunnels, wearing a G3 and I am 100% certain  it would have hurt a lot more without a helmet. So in my opinion, your claim that a G3 or any helmet without certification  gives no (or negligable) protection is nothing but bs.

Certification is nice, it tells me that a certain level of safety is guaranteed. But it does not mean that the reverse is also true, that a non-certified helmet has to be inferior. It just might be. 

 

hahah, because something hurts or not is a great way to judge the amount of energy transferred to your brain. I've hit my head on lots of stuff in the plane, including being a rookie and taking the door to the head. Would it have hurt a lot without a G3 on, obviously. Am I stupid enough to think that if that blow was hard enough to give me a concussion the helmet would do anything significant to lesson that blow? Absolutely not.  I'm not saying it is zero, obviously the shell deflecting and the liner mushing will absorb some energy. I am saying that instead of a concussion its lowered to a headache, or instead of a TBI it is lowered to a concussion. That difference is critically important. But sure, the G3 might make sure you have a pretty face while you suffer from PCS, or recover from a TBI. 

Edited by meat.missile
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Back when dinosaurs roamed the Earth, motorcycle helmets had their first (I believe) impact standard in the US issued by the DOT.  Many years later, a private organization issued the Snell standard because it was recognized that helmets could, and should be much better. The Snell standard was much tougher to meet.

At some time in the future, we may conclude that the standard to which the G4 complies is inadequate. It would be wrong to say that standard provides insignificant protection just because a better standard might exist.

I only wanted to know how insignificant a G3 is compared to the G4. Is that somewhere in the deluge of documents?

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(edited)
45 minutes ago, sundevil777 said:

I only wanted to know how insignificant a G3 is compared to the G4. Is that somewhere in the deluge of documents?

No, that was just basic info about helmets and brain injuries for the other poster. 

I wonder what the energy transfer difference is between the G3 and G4 are? (That's how you frame it as curiosity.) I mean, I too am curious. But I also know the G3 isn't going to do much of anything to prevent a concussion. 

Edit: Here is some more topics to learn about.

http://js-cct.com/upfile/file/20170901/20170901103344_99689.pdf

 

Edited by meat.missile

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"But I also know the G3 isn't going to do much of anything to prevent a concussion. "

For the same impact, how much will a G4 protect the wearer compared to a G3?  

Motorcycle helmets failing actual testing with DOT certification;

https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/documents/final_sae_motorcycle_presentation_v2-tag.pdf

https://ultimatemotorcycling.com/2019/02/20/4-out-of-10-dot-certified-helmets-fail-government-performance-tests/

Reading this;

https://www.satra.com/ppe/EN966.php

After reading this, I don't know how much of an impact a helmet with this rating will take and leave me injury-free.  I also don't know if a G3 protects me the same, more, or less than a G4 from the same impact.

Derek V

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22 minutes ago, Hooknswoop said:

"But I also know the G3 isn't going to do much of anything to prevent a concussion. "

For the same impact, how much will a G4 protect the wearer compared to a G3?  

Motorcycle helmets failing actual testing with DOT certification;

https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/documents/final_sae_motorcycle_presentation_v2-tag.pdf

https://ultimatemotorcycling.com/2019/02/20/4-out-of-10-dot-certified-helmets-fail-government-performance-tests/

Reading this;

https://www.satra.com/ppe/EN966.php

After reading this, I don't know how much of an impact a helmet with this rating will take and leave me injury-free.  I also don't know if a G3 protects me the same, more, or less than a G4 from the same impact.

Derek V

The G3 protects you less than the G4 from the same impact. 

It also isn't about injury free. It is about reducing the severity of the injury. 

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1 hour ago, meat.missile said:

The G3 protects you less than the G4 from the same impact.

Yes, you keep repeating that.

Simple fact is YOU DON'T KNOW THAT, you are just assuming it.

 

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2 hours ago, meat.missile said:

 

Thanks, that is interesting to read.

"Scope
This European Standard specifies requirements and test methods for protective helmets used in
paragliding, hang gliding and flying with ultra-light aeroplanes."

 

So... this  "certification" is not even valid for skydiving?  I'm quite sure that a helmet which is certified for flying ultralight planes will only give a negligable advantage in skydiving. I can tell that you don't care about about protecting your brain. You care about bumps and scrapes which a non-impact rated helmet is handle well. When it comes to preventing damage to the brain caused by blunt impact like a baseball bat, the ground, or another skydiver, a non-impact rated helmet is not going to substantially limit the amount of force transferred to the brain

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All kidding aside, I actually think its a good development that manufacturers are testing the performance of their products. Its just that I cant stand the claim of "improvement" without even testing the old situation, this is nothing but empty marketing hype.

 

 

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37 minutes ago, evh said:

All kidding aside, I actually think its a good development that manufacturers are testing the performance of their products. Its just that I cant stand the claim of "improvement" without even testing the old situation, this is nothing but empty marketing hype.

 

 

Quite right.

One would think that if the G4 was such an improvement, Cookie would be advertising about it, with graphs and videos from the tests and such. I would expect that skydivers being the tech wonks that we are, we would eat it up. Many more people would be replacing their G3 if there were solid data to back up the improvement. We are left to wonder if the numbers actually are impressive.  The standard to which the G4 complies might result in 50% less g loading, or 5% or who knows what? That standard may be no more ambitious than the old DOT motorcycle helmet, which was not at all ambitious.

 

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(edited)
56 minutes ago, evh said:

So... this  "certification" is not even valid for skydiving? 

Don't get your certifications mixed up. The poster you quoted was quoting one sample airports helmet standard.

The G4 helmet is certified to the French AFNOR "Skydiving and Wind Tunnel Helmet Standard XP S 72-600"

The Tonfly TFX for example is certified to that same standard, plus EN966: 2012 + A1: 2012, category HPG for AIRBORNE SPORTS
 I'm not sure why you would be all against a hang-gliding/paragliding/microlight airsports standard -- unless you came up with some very specific technical objections based on actual facts. (Hooknswoop provided a link to some EN966 info)

EDIT: Standards can be frustrating because one can't always download the actual standard (without paying a lot of money for them). More searching on the web would be needed to help understand how XP S 72-600 compares with other prior standards, what things are emphasized or not.

Edited by pchapman

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(edited)
2 hours ago, evh said:

Yes, you keep repeating that.

Simple fact is YOU DON'T KNOW THAT, you are just assuming it.

 

Dumb, just dumb. 

 

1 hour ago, pchapman said:

EDIT: Standards can be frustrating because one can't always download the actual standard (without paying a lot of money for them). More searching on the web would be needed to help understand how XP S 72-600 compares with other prior standards, what things are emphasized or not.

Standards are a pain. To add some more info, XP S 72-600 is EN966 + some stuff relating to snag resistance. But as far as impact goes, it is the same. (I can't find my source on that, but I'll keep looking for it.)

Edited by meat.missile
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