epsdan
Well-known member
Consensus is that Dale Sr died from a basilar skull fracture, and his injury/death was one of the drivers (no pun intended) behind getting the HANS accepted.
Take a look at a piece Dr. Jim Norman wrote after Sean Edwards death last year.
http://blog.parathyroid.com/race-car-deaths-medical-causes-racing-deaths/
Jim Norman (the above author) has done a lot of looking into this - and he's a driver, like all of us. I believe it's in this article, but he had an admitted bias against the HANS when it came out. Mat Pombo, another doc and good friend that I race with, is also very involved in head and neck injury research, and is a huge fan of the HANS. My "Basic Sense" (used to be "common sense", but it's not so common anymore), tells me a HANS is a reasonable investment, to avoid risk. I'm don't wear magnets on my knees to make them feel better - I know of know mechanism that could be responsible for a correlation (assuming there is one) between magnets and improved joint pain. The correlation between a HANS and you head not flying off your neck is pretty obvious.
Greg's numbers got my attention - I'm a number's guy (and it drives my wife crazy, but she's an absolute saint, so she tolerates it). I have no idea how much displacement that the head can tolerate before it goes on it's own way without the neck, nor do I know how much restraining force the neck muscles can provide to stop the head from flying off it's God-given perch. I do know, however, that I can only lift about 45#x10 reps in the gym with my neck, so that gives me an order of magnitude.... and tells me my neck muscles may very well need help in the event of a crash in a racecar...
Referring to Jim Rice's crash (in the E36 ST car mentioned above), I was on track when that happened. I race in the same class, so I assume my speeds at T8 are comparable. Checking my AIM data, I'm at between 100 and 110 mph (161-177 km/hr). Assume the head/helmet weighs of 15# (6.75kg mass) (Greg's assumption, which I think is decent). The big deal here is deceleration time. If we assume two meters (~6 ft) to decelerate from track speed minus a bit to zero (you hit a stationary object, like a wall), that will happen in somewhere around 40 ms. That results in a deceleration of somewhere between 1000 and 1500 m/s/s. In rough terms, this says the head is putting ~7000N, or 1500 lb-f on the neck. I don't think I'm man enough to withstand that without a HANS. Check my numbers - I showed my work! (Greg - no partial credit for you). There may be an error there, but I'm not seeing it.
Obviously, there are big error bars on this calculation. Unless I made a mistake, though, the deceleration time is tiny, thus the deceleration, and therefore force, is very large. I'm always open to correction - this was kinda on the fly, but tell me where I'm wrong.
One way or the other, I'm sticking with my HANS (or next gen, randy, I'm good either way), and hope my racing friends do too. I like you guys too much to lose you to an avoidable injury. Not a scare tactic, just honesty...
dan
Take a look at a piece Dr. Jim Norman wrote after Sean Edwards death last year.
http://blog.parathyroid.com/race-car-deaths-medical-causes-racing-deaths/
Jim Norman (the above author) has done a lot of looking into this - and he's a driver, like all of us. I believe it's in this article, but he had an admitted bias against the HANS when it came out. Mat Pombo, another doc and good friend that I race with, is also very involved in head and neck injury research, and is a huge fan of the HANS. My "Basic Sense" (used to be "common sense", but it's not so common anymore), tells me a HANS is a reasonable investment, to avoid risk. I'm don't wear magnets on my knees to make them feel better - I know of know mechanism that could be responsible for a correlation (assuming there is one) between magnets and improved joint pain. The correlation between a HANS and you head not flying off your neck is pretty obvious.
Greg's numbers got my attention - I'm a number's guy (and it drives my wife crazy, but she's an absolute saint, so she tolerates it). I have no idea how much displacement that the head can tolerate before it goes on it's own way without the neck, nor do I know how much restraining force the neck muscles can provide to stop the head from flying off it's God-given perch. I do know, however, that I can only lift about 45#x10 reps in the gym with my neck, so that gives me an order of magnitude.... and tells me my neck muscles may very well need help in the event of a crash in a racecar...
Referring to Jim Rice's crash (in the E36 ST car mentioned above), I was on track when that happened. I race in the same class, so I assume my speeds at T8 are comparable. Checking my AIM data, I'm at between 100 and 110 mph (161-177 km/hr). Assume the head/helmet weighs of 15# (6.75kg mass) (Greg's assumption, which I think is decent). The big deal here is deceleration time. If we assume two meters (~6 ft) to decelerate from track speed minus a bit to zero (you hit a stationary object, like a wall), that will happen in somewhere around 40 ms. That results in a deceleration of somewhere between 1000 and 1500 m/s/s. In rough terms, this says the head is putting ~7000N, or 1500 lb-f on the neck. I don't think I'm man enough to withstand that without a HANS. Check my numbers - I showed my work! (Greg - no partial credit for you). There may be an error there, but I'm not seeing it.
Obviously, there are big error bars on this calculation. Unless I made a mistake, though, the deceleration time is tiny, thus the deceleration, and therefore force, is very large. I'm always open to correction - this was kinda on the fly, but tell me where I'm wrong.
One way or the other, I'm sticking with my HANS (or next gen, randy, I'm good either way), and hope my racing friends do too. I like you guys too much to lose you to an avoidable injury. Not a scare tactic, just honesty...
dan