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If You Race A Car, Wear One Of These Life-Saving Devices
By Ron Lemasters, Jr.
If you’ve followed racing for the past two years, then you know
what a head-and-neck restraint system is. You know why it exists and what
it does to help prevent injuries to the brain.
Knowing all that, and assuming you drive a race car, own one or help make
it go fast, why don’t you have one of these systems or make sure
your driver has one on?
A head-and-neck restraint system is just as much a part of your racing
effort as tires, wheels and an engine, or at least it should be. It’s
all there, in black and white. Test data garnered from crash tests using
instrumental dummies tell an interesting story. Boiled down, that story
is either wear one or die.
That might seem a bit dramatic, but it’s the truth. The majority
of head-and-neck injuries in racing are caused by the neck trying to do
its job and failing against the massive force exerted on drivers by impacts
with walls or other cars.
Following the death of Dale Earnhardt at Daytona in 2001, there was a
massive investigation into the circumstances of the crash. In the course
of that investigation, the investigators determined that the change in
velocity—otherwise known as the Delta V—generated in that
fatal crash was 42 mph. Delta V is not about how fast you’re going
on the track. It’s about how fast you hit the wall and how fast
you come off it.
If Earnhardt’s Delta V was 42 mph, then how difficult is it to imagine
that the Street Stock or Late Model you drive can generate that kind of
force? If you’re traveling 50 or 60 mph, hit a parked car or something
and stop, that’s more than enough force to generate a head or neck
injury. You don’t have to be racing at Daytona or Talladega to generate
this kind of impact.
Trevor Ashline, whose résumé lists Swedish restraint-system
manufacturer Autoliv in addition to BSR, is the inventor of the Hutchens
Device. It is one of two devices mandated by NASCAR and other sanctioning
bodies for its drivers. His advice to racers of all stripes, budgets and
abilities is: wear it.
“There’s no reason not to, especially a harness device like
this one,” he says. “There are no negatives.”How much
are you worth? For the cost of a quality racing suit, you can outfit yourself
with something that will give you a chance to survive a heavy impact.
The Hutchens Device in its current form costs $300-$325, depending on
the bottom-end hardware for the buckle system. Ashline recently debuted
an alternate version of the original, and its cost is $400. The difference
in the two is that the new unit does not buckle into your safety harness.
It uses your body’s own structure to keep your head in place and
out of lethal range.
“Once you put it on, you can hook the helmet to it outside the car,”
Ashline says. “When you get in the car, you just pull it snug. When
you sit down, the points change. You’re using body kinematics (motion)
to tighten the belts up. This one (the new unit) has a rebound strap on
it, where it will try to catch your head going back. I’ve equaled
the best numbers I’ve ever gotten on the original Hutchens. The
original hooks to the belts as its anchor; the new one uses your pelvis
as its anchor.”
What you’ll get upon purchasing either one is: the harness, leg
straps, two upper tethers and the hooks for the helmet, along with the
screws for the helmet.
The HANS Device ranges in price from $1,275 to $2,000, depending on the
type of racing you do.
Neck Collars
OK, the price tag is a little steep for some of the more budget-conscious
racers out there. Why not just pass on the Hutchens and go with a neck
collar?
“Neck collars don’t do it,” Ashline states. “The
people who thought that worked believed that the head just rotates down,
and it doesn’t in a crash. The head first translates forward. Your
upper torso belts hold you back, and your head goes straight forward until
your neck tries to pull it down. You get full extension, you load the
belts all the way and you’re (neck is) out here like this (three
or four inches), then your neck starts to pull you down and it misses
the collar altogether. You’ll never hit the collar.
“Does the collar work with a Hutchens device?” Ashline continues.
“Yes, because you have the collar in close to your neck. The Hutchens
Device is limiting the stretch of your neck, and it’s going to force
your head down. That will help you because the rotation of your head as
it is pulled down gets you into the collar. I don’t disagree with
using a neck collar with a Hutchens Device. If you do not use a Hutchens
or a HANS, you’re playing with fire. Your neck can’t hold
the forces of the weight of your head, trying to take it off the top of
your shoulders.
The Hutchens Device and the higher-dollar HANS both act on the same principle:
They limit the loading on the weakest joint in the human body in terms
of impact. Your neck is very strong when it’s holding your head
up under normal gravity. When impact forces of 800 to 1,500 pounds (1
Newton = 0.2248 pound of force) are at play, it’s a weak collection
of bones held together with discs and ligaments. Don’t be misled
by the fact your Street Stock only reaches 80 mph. Forces generated from
an impact at that speed can kill you just as dead as impacts at 160 mph.
“Load limiting is the key,” Ashline says. “Restrain
the occupant early, limit the load the occupant sees and then ride them
out. That’s the key. You don’t want them to spike. The spike
comes when you restrain late and everything hits quickly. If you restrain
early, you can take that force out, and if you use some kind of load-limiting
device, like the Hutchens Device ... it comes in early. Because it does,
you never really get the high (load) numbers. It brings you up, over and
down, and that’s what you want to see.”
The first thing you want to do is to have your pelvis locked down in the
seat.
“In the first 20 milliseconds, you’ll start loading up the
belts as the occupant moves forward,” Ashline explains. “As
that forward movement starts, the occupant tightens the belts. The biggest
thing you want to do in any type of crash is to lock down the pelvis and
reduce the amount of movement there early. Then it’s easier to control
the chest and the head. Center of mass is your pelvis, and it can handle
a lot more g-forces than the rest of you can. When you lock the pelvis
down, you have this load on your lap belt that’s 2,500-3,000 pounds.
That provides a really good anchor for the (original) Hutchens device.”
He continues, “The straps that go up the back are very heavy material
with low elongation. As your head starts to go straight forward, it tightens
up the straps. The upper torso starts moving because your pelvis is locked
in and rotates into the upper belts. It limits the amount of movement
your head is going to see. The device comes into the lap belt, and the
lap belt is under so much load there is no way the harness is going to
move it. The helmet straps limit the whipping motion of the head.”
Lab Tested
Ashline, as an engineer, recommends that whatever you decide you need
for a head-and-neck restraint, make sure the product has been tested under
laboratory conditions.
“You learn how to watch the kinematics, learn where the loads are
going,” in a laboratory/crash sled setting, he explains. “The
only way you get to do that is to run your own sled tests. The (safety)
guys who are out there who aren’t doing sled testing have no idea
what they’re doing. You can sit there all day long and say, ‘my
thing is the best in the world.’ You put that on a sled test and
that will tell you. That’s the only way you can do it, in a laboratory
setting where you can study the motion and see how your system interacts
with the rest of the systems in the cockpit. If you’re not doing
that, don’t go there, don’t buy it, don’t even think
it’s going to be right.”As for the HANS, developed by sports-car
racer Jim Downing, it does its job well, according to Ashline. “The
end result stays the same, and that’s good,” Ashline says.
“The HANS is a good product, it works well. I’ve done a lot
of testing on it. They are just going a different way than I am.”
While this article is focused on head-and-neck restraints, there’s
more to this than just going out to buy a Hutchens Device or a HANS Device.
All systems in the cockpit—belts, restraints, steering column, seat,
padding, etc.—work together, and if they are working in concert,
the result is a better opportunity to survive a crash.
Seat Belts and Head Padding
One piece of advice Ashline gave that applies across the scope of racing
is on seat-belts. “The seatbelt and the seat are the number-one
things you can do to be safe,” he says. “Mount your belts
correctly. If you can get good geometry on your seatbelts, you are so
far down the road into a good restraint system it’s not funny.”
Seatbelt manufacturers supply mounting instructions—use them.
Padding around your seat’s head restraints is important too. Ashline’s
advice is to go with thicker, more impact-absorbing padding there. “Formula
One, the IRL and CART require three inches of energy absorption padding
around their headrests,” Ashline says. “It doesn’t give
you a big spring-back. You want something that rides you down and is strain-rate
dependent—which means that the faster you ride into it, the more
energy it will absorb. We’re working with urethane foam right now,
which is harder than other types of foams and gels. The visco-elastic
foams and gels are temperature-dependent, so when it gets cold or hot,
they do too. The gels are heavy, too. You need a minimum of three inches.”
The idea for this story is to get you, the racer, to think in terms of
safety in ways that are outside the old standby. If you drive a racing
car, whether it be a full-on Late Model or a Hobby Stock, you need one
of these devices, just like you need a helmet, firesuit and gloves. It
is not a question of whether you can afford one. The question is rather,
can you afford not to have one?
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