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Recent NASCAR deaths
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Driver
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Year
|
Track |
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Dale Earnhardt Sr.
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2001
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Daytona Beach |
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Tony Roper
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2000
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Fort Worth, Texas
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Kenny Irwin
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2000
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Loudon, N.H.
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Adam Petty
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2000
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Loudon, N.H.
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John Nemechek
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1997
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Homestead, Fla.
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Rodney Orr
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1994
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Daytona Beach |
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Neil Bonnett
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1994
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Daytona Beach |
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Clifford Allison
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1992
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Brooklyn, Mich.
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J.D. McDuffie
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1991
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Watkins Glen |
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Grant Adcox
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1989
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Hampton, Ga.
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Recent CART deaths
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Driver
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Year
|
Track |
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Greg Moore
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1999
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Fontana, Calif.
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Gonzalo Rodriguez
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1999
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Monterey, Calif.
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Jeff Krosnoff
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1996
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Toronto
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Recent Formula One deaths
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|
Driver
|
Year
|
Track |
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Ayrton Senna
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1994
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Imola, Italy
|
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R.
Ratzenberger
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1994
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Imola, Italy
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Ricardo Paletti
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1982
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Montreal
|
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Gilles Villeneuve
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1982
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Spa, Belgium
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Recent IRL/USAC deaths |
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Driver
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Year
|
Track |
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Scott Brayton
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1996
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Indianapolis
|
|
Jovy Marcelo
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1992
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Indianapolis
|
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Gordon Smiley
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1982
|
Indianapolis
|
|
This isn't
going to be a NASCAR love-story. As great a series as NASCAR is, when
it comes to safety they have missed the boat. We hate to hit a man
when he is down, and NASCAR certainly is down right now, but perhaps now is
the time to lay it on the line and get it over with.
NASCAR is an incredibly
successful sport. Everything they seem to touch turns golden.
Their TV ratings are through the roof, their race attendance is second to
none, their merchandising is stellar, their fans are extremely loyal, and
their races are close and entertaining. Almost anyway you measure it,
NASCAR has done everything right. Except for safety. They get a
big 'F' in that category.
When it comes to making the
races more entertaining for the fans, NASCAR spares no expense. They
change rules to make the cars equal to one another so their races are close
and entertaining, sometimes weekly. They impound cars and take them to
the wind tunnels, and they impound engines and take them to the
dynamometers. If anyone works hard and gains an advantage, NASCAR
takes it away. Equality is the name of the game. But that's the
problem. It appears, at least on the outside, that NASCAR will spare
no expense to make their 'shows' better, yet when it comes to safety, it's
an after thought.
With all the wealth that NASCAR
has, one would think they would have a research and development division
that is responsible for safety. A group that would set standards and
implement changes. Instead they reply on Humpy Wheeler dropping cars
from a crane onto soft walls, and the drivers to decide whether they should
wear the HANS Device. What is NASCAR doing to fund proper
testing? Eurointernational, for example has a 'soft
wall' that is the
only one that meets FIA standards. Although the FIA set the standard
with head-on collisions in mind (ala Michael Schumacher and now Dale
Earnhardt), Eurointernational claims their IPS soft wall will in
fact work even better on oval tracks.
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A lesson in Physics for concrete wall crashes
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The following physics exercise is meant to give you an understanding of
the force a car strikes a solid concrete wall with and the forces that a
'soft wall' deal with. The actual forces the driver feels is a bit
more complicated and is directly related to how much 'crush' zone a car
has. In rough terms, a race car needs a crush zone of about 3 feet
to keep the 'g' forces a driver feels in the 50 to 60 range, a range
thought to be survivable in almost all cases.
An object in motion has kinetic energy. The magnitude of the kinetic energy depends on both the mass and the speed of the object according to the equation:
E = 0.5mv2
where m is the mass of the object and v2 is its speed multiplied by itself. The change in a vehicles energy, ‘delta E’, can be derived from the equation:
‘delta E’ = (m x a)d
where ‘a’ is the acceleration (or deceleration, also known as negative acceleration) applied to the mass, ‘m’, and ‘d’ is the distance through which ‘a’ acts. For an object subjected to a planet’s gravitational forces, the ‘m x a’ portion of the second equation, mass ‘m’ times acceleration ‘a’ is equal to an object’s weight (also known as force), something we all can relate to. Because the acceleration due to gravity on earth is a constant, your weight is a function of your mass, or the amount of matter you are made of. For example, the body of a small person is made up of less matter/mass than a large person. Hence the large person has more matter/mass, and hence more weight (m x a).
When an object is lifted from a surface a vertical force (gravity) is applied to the object. As this force acts through a distance, energy is transferred to the object. The energy associated with an object held above a surface is termed potential energy. If the object is dropped, the potential energy is converted to kinetic energy as it accelerates ‘a’ due to gravity at the rate of 32.17 feet per second squared. The further the distance ‘d’ that object accelerates due to gravity the more energy it gains.
Once an object is no longer accelerating or decelerating it is no longer gaining or losing energy. In other words, a car traveling at a constant velocity has energy equal to the first equation, but it is not gaining or losing energy as per the second equation because ‘a’ = zero. In outer space, that same object has no weight nor energy in the vertical direction because there is no acceleration downward due to gravity. However, it can have kinetic energy if propelled in any direction.
The kinetic energy of a vehicle hitting a wall is a function of it’s mass (i.e. density), the angle at which it hits, and the velocity in the horizontal direction, and can be represented by the following equation:
E = 0.5m(v
sin(t))2
where t = the angle between the vehicle’s center of mass as it impacts the wall, and a tangent to the wall at the point of impact. If we assume an average impact angle of 30 degrees or less, the actual energy of the car hitting the wall is 25% of what it would be head-on (sin 300 squared = 0.25). Therefore, shallow angle impacts tend to be less severe than more direct hits.
We have heard that drivers sustain loads as high as 100 g’s in an accident. 1 ‘g’ is the force equal to one earth’s gravity on your body. 100 g’s would be equivalent to a person lying on you weighing 100 times as much as you. Not a pretty sight I’m sure.
Although the general public is familiar with the term ‘g’ forces in a racing accident, actually gravity has nothing to do with the severity of a crash. The same race car traveling at 200 mph in outer space (and weighing zero) hitting an immovable concrete wall would sustain the same damage as it does here on earth. Gravity acts in the vertical direction. For the most part, a race cars velocity (and energy) is
in the horizontal direction. So gravity, or ‘g’ forces are just a way for the average person to understand the magnitude of the force felt by the driver.
Let’s try to explain this in simpler terms. If a bird feather, which is not very dense (i.e. it has almost zero mass), were to impact a wall at 200 mph, it would
hit with very little force because it has almost zero energy to dissipate
with a mass that's almost nothing. Likewise, an Indy Car traveling at 200 mph has less than 1/2 the energy of a 200 mph NASCAR Winston Cup car to dissipate because it has less than 50% of the mass. That same Indy car has four times as much energy to dissipate at 200 mph than it does at 100 mph because energy is a function of speed squared. To look at it another way, a crashing car would apply a force 4 times as great on a concrete wall at 200 mph than it would at 100 mph.
The trick to driver safety is to dissipate the energy of the vehicle over a distance great enough to allow the drivers body, and the car, to decelerate at a reasonable rate. To exaggerate what I mean let’s use this analogy - if a 200 mph Indy car gradually comes to a stop in 1,000 feet, the driver feels very little ‘g’ forces on their body because the deceleration ‘a’ is very small. If a 200 mph race car hits a wall head on and comes to a stop in the distance it takes for the front of the car to crush against the driver’s body, fatal injury results because the deceleration ‘a’ is very large and the immovable wall exerts an equal and opposing force (i.e. the mass of the car and driver times a very large deceleration ‘a’ against the car and driver, until they stop. The human body can not withstand that amount of force.
However, the key point to understand
here is that either the walls will have to crush about 3 feet, or the cars
will need crush zones of about 3 feet to keep the 'g' forces the driver
feels in the 50 to 60 range (3 feet was derived from knowing the range of
speed a race car might hit a wall). In other words, it's not really
the mass of the vehicle that will determine how much 'g' force a driver
feels, but the amount of distance the car decelerates over a given time
period. The only real issue with vehicle mass is the design of the
vehicles crush zone. A heavier vehicle will require a stronger, and
possibly more complicated crush zone. Winston Cup cars need properly
designed crush zones, and if they weighed less, the design of that crush
zone would be a little easier. The crush zone must work not only in
head-on accidents, but in accidents up to about 30 degrees as well.
We will address crush zones in another article and urge NASCAR to start
designing them into their cars as soon as possible.
|
Why doesn't NASCAR fund the
installation of the IPS barrier on an oval race track in one of the turns,
instrument remote controlled cars, and crash them into the wall at various
angles to see how well it performs? Why does a track owner like Humpy
Wheeler have to drop cars from a crane to test soft walls? It's up to
the sanctioning body to set safety standards, not the track owner.
NASCAR (CART and the IRL are just as much at fault) should impose safety
standards on the track owners, and the track owners should be made to adopt
them. Spend some of that TV money where it can best be utilized.
Racing can't afford to lose another Dale Earnhardt or Ayrton Senna.
Every year the FIA inspects F1 race tracks. Either the track owner
makes the safety changes the FIA dictates, or they lose their race.
Period. End of story.
Research proves that the HANS
Device works, yet NASCAR yielded to the drivers to decide whether to wear
them. Whereas CART was proactive; they funded research on the HANS
Device to make it safe and comfortable for the drivers and then mandated
it's use; NASCAR took a wait and see attitude. The drivers cry was -
"it's too restrictive" or "it's too
uncomfortable." Well guess what, after Sunday's tragedy, who's
crying now?
Uncomfortable? Fire suits are
hot and safety harnesses are restrictive, but the drivers are required to
wear them, whereas years ago they were not. Why is it that the racing
industry is reactive rather than proactive when it comes to safety?
Why do numerous driver or fans have to die first before anything is
done? Why isn't there a dedicated group devoted to making things safer
before tragedy strikes, rather than after? Why does Scott Pruett and
the PPI team have to take it upon themselves to test modified HANS Devices
with quick-releases, and modified seats that wrap around a drivers head ala
open wheel cars, to make the driver safer? (Note - Pruett demonstrated this
on RPM2Night on 2/20/01).
17 out of 17 of the most recent
deaths have been as the result of severe head or neck injuries. That's
a perfect batting average folks. It's clear the head and neck are the areas
that need protecting and the HANS Device is a key component in that area.
NASCAR prides itself on its
heritage. It's cars have not really changed all that much since the
50's compared to other forms of racing. Calling them 'stock cars' is
part of the heritage of NASCAR and they go to great pains to preserve their
history and their image. Sophisticated space-age materials are almost
non-existent in a 'stock car', materials that can make the cars safer.
Not only are composite materials lighter, they are also stronger than steel.
What's most disturbing is that
respected people within the NASCAR community get on TV and make statements like Winston Cup cars are the
safest racing cars in the world, when in fact the evidence shows other wise
(see death sidebar above). Sure, NASCAR drivers walk away from flips
and crashes much worse then Dale Earnhardt's all the time, but the fact is,
those flipping race cars are dissipating energy and are much less likely to
be fatal than head-on type crashes such as Earnhardt's.
Anyone who thinks a steel roll
bar car with a sheet metal skin is the safest thing man can build, clearly
is misinformed. A 'stock car' is about as unsophisticated as it gets,
and that includes safety. Although far more expensive, composite
materials in the car would allow the cars to be lighter, and therefore, have
less energy to dissipate, meaning the cars crumple zone would be easier to
manufacture without being overly massive. The heavy weight of a Cup car
somewhat works
against the drivers safety in that respect.
My father, who was a tank
commander in World War II, tells the story about the time they were hot
dogging it one day and decided to try and run over a 9" diameter tree
with their Sherman Tank. They were in for a rude awakening when they
hit the tree at about 30 mph and were stopped dead in their tracks.
The impact was so great they all nearly died. What they didn't realize
at the time, was that they were better off hitting the tree in a vehicle that
deformed and crumpled, than one that was as rigid as a tank. In
crashes, the more a vehicle deforms, the less the 'g' forces the driver will
feel (see sidebar).
So to say a Winston Cup car is
as safe as it can be is just plain wrong. We're not suggesting NASCAR
start mandating 100% composite material cars like a CART Champ Car, but we
are certain space-age materials can be implemented in key areas of the cars
to make them have better crumple zones without those zones being overly
massive because the car weighs so much. As we said above, it also
would help if the cars were lighter because the crumple zone would have to
deal with dissipating less energy.
CART Champ cars hit walls at far
greater speeds than Winston Cup cars, yet their death rate is not any
higher, and in fact lower, because the cars have better crumple zones.
The Winston Cup car chassis has become stiffer over the years with many
different bars added to strengthen the chassis for various reasons.
However, this added stiffness reduces the driver's safety. Would the
cars cost more to add better crumple zones? You bet. But what price do you place on a drivers
life?
Head-on crashes usually happen
at 50 mph or less. Although Earnhardt was going 180 mph when he
crashed, in fact his speed into the wall was something much less.
Ditto for Adam Petty, and Kenny Irwin last year, and Jeff Andretti at Indy
years ago. The velocity vector perpendicular to the wall in fatal, or
near fatal, accidents is almost always very small. But hitting a wall
head-on at even 50mph is devastating and many times not survivable without a
HANS Device and perhaps a soft wall.
Another bone of contention is
the lack of a full time medical staff that travels with the NASCAR circus to
every race. CART has a staff of medical doctors who travel to every
race to tend to the drivers. They are highly trained in racing type
injuries and know how to best administer first-aid immediately after a
racing accident. These same doctors also get involved with safety
related issues. NASCAR relies on local doctors a each race, which
means the drivers see a different doctor every weekend. Doctor's who
may be good, but their primary job is not racing related.
And there's more. Why doesn't NASCAR use the "CRASH BOXES" that both CART and the IRL use? GM and
Ford both make these for CART and the IRL to use, and they can be bolted right in. The other thing is NASCAR not allowing the use of "DATA Collection
Systems". Most of the teams have this equipment for testing but are not allowed to use it for race weekends. This would not make the racing safer
right away but at least they would have data from accidents to look at and see what they need to change to make things safer. That is the sad fact from
all of the recent NASCAR fatalities, they have no on board data to look at for speed, G's, throttle position, brake
pressure, etc. They only have guess's.
HANS Device. Soft
Walls. Composite materials. It's a sad state of affairs to think
it takes the death of a great driver like Dale Earnhardt before the racing
industry wakes to the fact that more should be done in the way of
safety. It's time for our industry to take their heads out of the
sand. It's time that safety become the #1 issue in auto racing. Instead
of just giving it lip service, it's time for NASCAR, CART and the rest of
the USA race sanctioning bodies to fund the construction of a safety test
center whose sole purpose is to improve safety in racing. Too
expensive? Can we afford not to do it?
The author can be contacted at markc@autoracing1.com
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