Self explanatory:
http://forums.bimmerforums.com/forum....php?t=1753248
Scroll down to video....on third page are pictures of the aftermath. Now, tell me you don't need a H&N device??? Chuck
Printable View
Self explanatory:
http://forums.bimmerforums.com/forum....php?t=1753248
Scroll down to video....on third page are pictures of the aftermath. Now, tell me you don't need a H&N device??? Chuck
Haven't watched the video, but can already tell you I don't need an H&NR device.
GA, whose HANS came FLYING out from under the shoulder harnesses after the first hit during a high speed wreck at Watkins Glen, right before hitting the wall two more times. Having to choose between HNR or tight belts when hitting the wall? Priceless.
I don't need a H&N device.
Neither the video nor the photos demonstrate the need for such a device... i.e. what were the g forces?
Most importanly, even if the video demonstrated the need for a H&N device, it certainly doesn't demonstrate the need for a SFI 38.1 device.
My only run in with a wall was during 3 day racing school in a Formula Skip Barber at LRP. went thru 11 too hot, let up on the throttle. hung the tail out(rear engine) and came around. Hit the outside tire wall sideways at 80+. No HANS but my head and neck were ok, despite all the lateral movement. Broke a couple ribs. don't know what would have happened without a H&N if I had hit the tire wall head on...but I guess an OZ of prevention(HANS,ETC) might be worth a LB of cure. Obviously, it didn't help Greg when it failed to work correctly!!
I've always wondered about that ... My Ultrashield harness has a velcro attachment from shoulder belt to shoulder belt
Think that would prevent the Hans flying out ?
FWIW : I live with neck pain every day that started after a pre HANS crash. In my case the HANS would not have helped ( hard RR impact into concrete wall on an oval ) , but I choose to be as safe as possible for the next time.
jjj..The wrecked E30 is a friend of mine. He calculated the G load in excess of 160Gs. The H$N made the wreck survivable....period. If you can't see that I feel sorry for you. Chuck (Someone who has hit/been hit 5 separate impacts while wearing the HANS.)
He speaks from the dead?
What specifically from the video, other than it being a hard hit -- which is not evidence of non H&N survivability --, is evidence that the crash would have been fatal without a H&N? You see what you want to see. If I show a priest a particularly interesting pattern on a loaf of bread, he's going to see Christ. An oven repair technician will see an oven that heats uneven.Quote:
The H made the wreck survivable....period. If you can't see that I feel sorry for you.
I had 3 before I got the device I can use for 3 more weeks. After that, nada. Obviously the Isaac is superior to your device as mine actually prevents impacts based on the evidence we both have presented.Quote:
Chuck (Someone who has hit/been hit 5 separate impacts while wearing the HANS.)
Ok, Greg....show us your mad math skills. 80mph to stop in about 18" is how many Gs? Copied from another forum:
a=V^2/2d.
a= 5194ft/sec^2. That's about 162g's.
All of my hits have been side impact save 1.
jjj, you are correct, the data does not show non survivability from the impact without a deceive. However, it does show a damn good possibility. That's good enough for me.
Greg, the newer HANS with the wings and use of a 2" shoulder belt solves the problem. I have had no such issues with mine, and I have given it a very fair chance. Chuck
No, you show us the data. Anything else is bullshit*.
GA
* Or semi-religious faith to an ideal that does not need proof.
On edit:
So what you're sayin' is, the prior version of the bible wasn't as good as it should have been -- despite its industry approvals -- and may actually have been more dangerous, and that if I just forget that one and spend more money on the new bible, everything will now be okay? What happens when the next edition comes out due to inconsistencies in v2...just keep swallowing?Quote:
Greg, the newer HANS with the wings and use of a 2" shoulder belt solves the problem...
Gotcha.
Greg, obviously you missed this: "Ok, Greg....show us your mad math skills. 80mph to stop in about 18" is how many Gs? Copied from another forum:
a=V^2/2d.
a= 5194ft/sec^2. That's about 162g's." (Oh, yea...make that -160Gs)
You know the track and the speeds in that area. I feel 80mph is a reasonable assumption...and yes, I know what assumption means.
Most people, when designing items, improve the items over time. That is just the way it is. Real life does not model on a computer or drawing board. That is why there are other items available. Sorry you had a bad experience, but haters are gonna hate. Accept this thread for what it was intended....an example of what can and does happen to good people. BTW, I don't think Scott was using a HANS but another device. Chuck
His H&N system could have helped or it may not have mattered.
Either way it was a hard impact, we've seen people hit that wall at that angle before without any H&N system at higher speeds and get right out, but is it worth trying if you can be better prepared with a H&N system?
Assuming 80MPH (which, unless I see the data logger, is probably a gross overestimation of the speed at impact) ...
80MPH = 117.333 feet/second initial velocity
0MPH = 0 feet/second terminal velocity
Delta = 117.333 feet/second
Delta ^2 = 13,767.11
Distance = 1.5 feet
Delta ^2/(2xDistance) = 4589.037
1Gee = 32 Feet/second^2
Gamma/Gee = 4589.037/32 = 143.4074 "Gees"
And if he had taken that deceleration, he would have had more significant internal injuries from the force of his organs and other soft tissues slamming into his body.
How many seconds was he sliding sideways? You scrub alot of speed off when the tires aren't rolling. At 60MpH, the deceleration is 80.67 gees. At 40MpH, the deceleration is 35.85 gees .Quote:
You know the track and the speeds in that area. I feel 80mph is a reasonable assumption...and yes, I know what assumption means.
And my ISAAC still remains superior as I have had zero crashes where it would have been useful while wearing it and you have had 1 where yours was useful. Obviously, the reasoning the ISAAC is a better device is that it works premptively and actually prevents impacts....
No, I ignored it, because it makes too many assumptions, and ignores too many other factors to be of anything other than an Internet argument. I'm an engineer, I know better.
Show me the data*. Otherwise, it's bullshit.
GA
* As in, data acquisition, proving your position rather than relying on Internet math.
And here is a video of that same device trapping someone in a car (1 minute mark). Covered in gas and can't get out of the car.... [ame]http://www.youtube.com/watch?v=KEtCGO9atzM[/ame]
And I'm not the best driver - but I saw that car dumping fluid and saw the crash coming way before it happened. I'm glad the driver is OK.
It's a little late for substantive arguments about the merits of various H&N designs, guys. Y'all (collectively) missed that boat.
K
Hey, he's on a roll.
;)
If any people ever deserved to be on double secret probation, it's some of us on this board...
" My advise to you , is to begin drinking heavily "
<sigh>
80 on track, likely 50 at impact
1.5 feet to 0 is ridiculous (0.013sec at 80)
let's make a table of "gees" vs decel time
dv = 50mi/hr * 5280ft/mi * 12 in/ft /((39.37 in/m)*3600sec/hr)= 22m/sec
accel = dv/dt
1g = 9.81 m/sec^2
decel
time , gees
0.05sec , 44g
0.10sec , 22g
0.20sec , 11g
0.40sec , 5g
my guess? at the average speed of (50-0)/2= 25mph = 36.6 ft/sec it would take
0.1 sec to move 3.66 feet, which considering the crush zone and the deflection
of the concrete barrier, seems reasonable
I'd say 22g +/- 11g (nowhere near 160g)
Early experiments showed that untrained humans were able to tolerate 17 g eyeballs-in (compared to 12 g eyeballs-out)
for several minutes without loss of consciousness or apparent long-term harm.[14] The record for peak experimental horizontal g-force
tolerance is held by acceleration pioneer John Stapp, in a series of rocket sled deceleration experiments culminating in a late 1954
test in which he was stopped in a little over a second from a land speed of Mach 0.9. He survived a peak "eyeballs-out" force of 46.2
times the force of gravity, and more than 25 g for 1.1 sec, proving that the human body is capable of this. Stapp lived another 45
years to age 89, but suffered lifelong damage to his vision from this last test.[15]
.
.
[quote=lawtonglenn;330744
I'd say 22g +/- 11g (nowhere near 160g)
[/quote]
But he was driving flatout and was seventh!
Don't forget David Purley...Quote:
Early experiments showed that untrained humans were able to tolerate 17 g eyeballs-in (compared to 12 g eyeballs-out)
for several minutes without loss of consciousness or apparent long-term harm.[14] The record for peak experimental horizontal g-force
tolerance is held by acceleration pioneer John Stapp, in a series of rocket sled deceleration experiments culminating in a late 1954
test in which he was stopped in a little over a second from a land speed of Mach 0.9. He survived a peak "eyeballs-out" force of 46.2
times the force of gravity, and more than 25 g for 1.1 sec, proving that the human body is capable of this. Stapp lived another 45
years to age 89, but suffered lifelong damage to his vision from this last test.[15]
.
.
He returned to Formula One in 1977 with his own LEC chassis designed by Mike Pilbeam and run by Mike Earle. It was this car in which he suffered serious injuries in an accident during pre-qualifying for that year's British Grand Prix. He survived an estimated 179.8g when he decelerated from 173 km/h (108 mph) to 0 in a distance of 66 cm (26 inches) after his throttle got stuck wide open and he hit a wall.[3] For many years, this was thought to be the highest g-force ever survived by a human being.[3] He suffered multiple fractures to his legs, pelvis and ribs.
I've seen this several times and continue chuckling... ...I enjoy it even more now that I see my car (red Scirocco, then owned by Tim Meyer) makes an appearance at the 3:21 mark.
I think I'll be handing over my H&R ransom to purchase the Safety Solutions Hybrid Pro Rage Restraint because it has side-impact tethers, low neck profile and torso straps...
That's why I went over to CHUMP. One class... basically no real rules other than to keep costs "down" and currently NO HNR rule other than you gotta have something. Belts get 4 years from manufacture date. You should find a team Tom. Guaranteed to have fun racing again ;)
I'm pretty much in Tom's boat as well. But I can still go solo untill the powers that be mandate H&N devices in auto-x.
Russ
Come do hillclimbs and Time Trials. No H&N requirement, 5 year belts... Heck, you can even run just a bar in some cars (though I'm not fond of that...). I can also tell you that if you have a competitive road race car in the northeast, you will be in great shape car-prep-wise at Time Trials. Most of our competitors are not at the car preparation limits...
COMSCC is a great club (non-SCCA) located in the northeast which I began running HPDE/TTs with back in 2005. They run at Mosport, Mont Tremblant (not every year though), NJMP, NHMS, WGI and a few others including Summit... http://www.comscc.org/. Another good HPDE club woud be PDA (NASA) and BMWCCA (I typically run with Patroon)
Given some info on LRP, I would say that they are going to be "marketing" to get alot more clubs there for track days this year.