This weekend is the Daytona 500, which, in most people's minds, is NASCAR's premiere race. If you are a racing fan, you may very well have been watching five years ago when Dale Earnhardt crashed in the last corner of the last lap of the race.

I certainly was.

As someone who watches a lot of racing—NASCAR, IRL, IMSA, American LeMans, F1, Champ Cars, Touring Cars, you name it—I see a lot of racing crashes.

As wrecks go, Earnhardt's didn't look all that bad. He turned up the banking from the middle lane, hit the wall, got whacked in the side by Kenny Schrader, and skidded to a stop.

Dead.

It was nothing like some of the topsy-turvy bouncing-flipping-sliding-spinning wrecks you see so often in NASCAR. It was nothing like some of the terrifyingly destructive crashes you see with formula cars where the engine, wheels, nose, tail and everything except the cockpit tear off in a brutal shimmer of carbon fiber and fire.

It wasn't dramatic at all, except in the sense of the drama of the story because of when it happened in the race. It was interesting as a part of the story, of the show, but somewhat disappointing as a wreck. It looked trivial, and yet it killed him. So you have to ask yourself why, especially if you're even an occasional racer, such a seemingly-benign event ended so catastrophically for Dale Earnhardt.

It turns out, he died because he was killed by his safety equipment.

The actual speed of Dale Earnhardt's impact into the wall was relatively slow. Although he and the rest of the cars were running somewhere in excess of 180 mph, the actual impact—that is, the speed of the vector into the wall—was, from what I have read, 42 mph. When you consider some of the incredible wrecks you see week in and week out in racing, 42 mph doesn't sound like much more than a love tap.

I mean, after all, those guys are surrounded by steel cages specifically designed to protect them in a crash. And, they're strapped into their seats with 3-inch wide, six-point safety harnesses. They wear helmets and fireproof clothing. 42 miles per hour? That's nothing.

Or, at least, you'd think it was nothing.

In fact, going straight into a wall at 42 mph is a pretty big deal. Let me give you the math. NASCAR race cars have a minimum weight of 3,400 lbs. When a car hits a wall there is some amount of crush at the point of impact; the front, in Earnhardt's case. I don't know for sure how much his car crushed but, looking at the photo, I'd guess about a foot.

So, you have a 3,400 lb projectile travelling at 42 mph and dropping to zero mph in 1 foot. Sounds a little worse that way, doesn't it? Do the calculations and you'll find out that, given those numbers, the force of impact was 100.3 tons, that's 200,600 lbs or, dividing by the weight of the car, 59g's. If he was going 43 mph instead of 42, the impact was 62g's. The forces, after all, build exponentially. Either way, that's a pretty good hit for such a mundane speed.

Actually, it's more than just a pretty good hit. It wasn't very many years ago that it was pretty universally believed drivers couldn't survive a crash of more than 70g's. That would be 46mph in this scenario. And yet, since then, since they started actually measuring impact forces, there are documented examples of drivers literally walking away from crashes of 130g's, so clearly 70g's is not the ultimate threshold between life and death.

So what's going on here?

What's going on is that Dale Earnhardt and, for that matter, Adam Roper, Kenny Irwin and Adam Petty—all of whom died in NASCAR crashes similar to Earnhardt's since 2000—was killed by his safety equipment. And, it wasn't because it didn't work; it was because it did exactly what it was supposed to do.

Let me explain:

Dale, and all these other guys, were strapped tightly into their seats with extremely strong and relatively unyielding racing harnesses which were, in turn, connected directly to the steel roll cage protecting them. On their heads were state-of-the-art racing helmets to keep their noggins safe. It's just what they were supposed to do—what the rules mandated, even—but it's also what killed them.

During the impact, during that moment of 60g's or so of deceleration, Earnhardt's body went straight forward into the grip of his harness at, since the harness successfully stopped him, 60g's. It stopped him within a few inches of where he sat, keeping him from hitting the top of the roll cage or the steering wheel, or the windshield, or anything else. It did everything it was supposed to. The problem was, the harness system was not designed, or even intended, to restrain the movement of his head.

That's what killed him. And, all the others, as well.

When the head is yanked forward with that much force (actually, 35mph—41g's—would have been enough), it is very common to suffer from what's called a basil skull fracture. What that means is the bone at the bottom of the back of your skull is literally torn off by the muscles and ligaments in the back of your neck. Although, like practically every other injury in this world, it's possible to live through such a trauma, the end result is usually a broken spine (a hangman's death) and/or bleeding to death from the torn arteries in the back of your head.

Not a very pretty picture. So, what could he, or more importantly, should he have done?

He could and should have used a device to limit the movement of his head. There are half a dozen on the market but the one that is indisputably the best and most protective is the HANS device. It's a simple little piece of carbon fiber that goes over your shoulders then around and up behind your head into a thin headrest of sorts. The shoulder harnesses keep it in place and tethers running from the headrest bit to your helmet stop the helmet (and your head) from moving more than a few inches forward of its normal position in relation to your body. Slightly restrictive, you can only turn your head a little way to each side, but critical in the event of a reasonably big crash.

In truth, doctors have said it's unclear whether the HANS device would have saved Earnhardt's life. That's something we'll never know. We do know he refused to wear one and now, as the result of a crash of the kind it was designed to protect drivers from, he is dead. We also know that in 2001, Bruno Junqueria, while practicing for a CART race (and wearing a HANS device), spun out of control and crashed into the wall at a full 200mph. And walked away.

It doesn't take a good grasp of Einsteinian physics to realize that if you're going to race cars you should have a HANS device. I've got mine. How about you?

Enjoy the 500 this weekend!

1. Kyle04/06/2008 09:50:55 PM

Pretty insperational

2. bob01/22/2009 02:26:28 PM

3. Larry Danielson02/11/2009 12:01:54 PM

Not to be picky, but it was Adam Petty (son of Kyle) that died in an on the track crash. Greatefully Kyle is still with us. Sadly Adam is not.
Again, not to be picky but the force of the car, stopping in such a short distance, and the body of the driver still moving until stopped by restraints is what kills most all driver's, making your assesment very accurate.
Simply stated, when the car stops so abruptly, the body cannot, thus the internal organs of the body continue at what ever spped the car was moving, then crashing into the natural cage of the body (rib cage, skull ect...) If Earnhardt would have been moving faster, his car would have had enough momentum to swing around, moving at such a slow speed the car lacked the momentum to skid out of Schrader's way, making that 42 mph very deadly.
Schrader's car hitting Earnhardt from the right side forced Dale's body one direction, and the impact on the wall almost instantly forced his body another direction. The result is very violent, even though the speeds were, by racing standards, very low.
As a former firefighter and EMT, I studied the impact of crashes to some extent, it was the fact that there is no way to stop the organs of the body from moving inside the framework of the skeleton. Many times that is what kills people on the highways also.
It is amazing more drivers are not killed in racing. That is a testement to the research and development in safety (and the skill of the drivers) that all forms of racing require.

4. Scott Good02/11/2009 01:26:11 PM
Homepage: http://www.scottgood.com

Larry,

Whoops. Adam it is. I'm amazed nobody else has caught that over the past thousand days or so. I've updated it in the post.

Thanks for your other observations, too.

Scott

5. Larry Danielson02/13/2009 04:35:02 AM

Scott,

Thanks for the rapid response. That was great. Thanks again.

We all know the HANS Device is a great safety precaution that NASCAR now requires all driver's to use, and for good reason! Too bad there is nothing like that in our personal cars...But there is something we have in our cars that NASCAR does not have...The AIRBAG!

I can say from my own experience that Airbags DO WORK!

A few years back I was involved in a head on colission at about 30 miles per hour whan a new Volkswagon Beatle hit me in my lane. Neither of us had time to apply the breaks. Both of our airbags did deploy and saved both the other driver and myself from any serious injury. There were no passengers in either car. Thankfully!!! My car was an older Plymouth with only a drivers airbag.

The 30 mph I was driving is much less than hitting a wall at 42 mph, but the other driver was going maybe 10 to 15 and the resistance equals out to about the same. Without the airbag, I MIGHT have suffered the same fate as Dale. Who knows?

(San Diego Padre and Charger fans may remember that Jack Murphy died in a low speed crash. Jack Murphy was a reporter for the San Diego Union-Tribune (Jack Murphy Stadium) that was sadly killed in an accident in the confines of a crowded city street in the downtown area of San Diego).

I was not belted in my car and I did slide under the airbag hitting the dash with my knees, suffering minor bruising and swelling. My own damn fault. But I was not seriously injured because the airbag did deploy. I did have minor abrasions to my face from my glasses hitting the airbag and scrapping my face, but other than that (and my knees)... NOTHING.

What I am saying is, when we mention that Dale's safey gear is what killed him, that can be stated as only partial truth. I believe the HANS Device may not have saved Dale, because of the side impact of Schrader's car, yet, it may have because it would have restrected the movement of Dale's head forward, but how far? Science may never be perfect in this area. Still, it is proven that in the driving that NASCAR does, everything that is implemented for safety is a studied and effective means of providing every precaution available.

The safety devices in our passenger cars are too. So from now on when anyone gets in my car, or I get in others, THE BELT IS USED!

During my nearly ten years on the fire department and EMS I have seen the difference between using the belts and not. It is nasty... and far more successful when the seat belt is applied.

Impact of the airbag with a belt across your chest is alot less serious than compressing the airbag and hitting the windshield anyway.

Also, manufactuers are now installing SIDE IMPACT AIRBAGS. From any studies I have seen, they ARE as effective as the front impact. Yet neither are as effective unless the belt is used. USE THEM.

I just wanted to make the point that we all live fragile lives, but with the efforts of safety engineering and common cents (meaning money well spent) it does not have to be as fragile as life once was.

Thanks again Scott, great job!

Larry.

6. Scott Good02/13/2009 09:00:19 AM
Homepage: http://www.scottgood.com

Larry,

Thanks for this additional perspective.

This is the single-most responded-to thread on my blog (you wouldn't know it because some time back I deleted all the redneck homages to Dale which, summarized, amounted to, "Dale wuz the greatest person who ever lived...WAHOOOO!") and I can't tell you how nice it is to have actual intelligent dialog here.

Much appreciated.

However, since you caught me on my erroneous Petty reference, I have to quibble with your math. A head-on accident into a fixed object (like a wall) is the same as hitting an oncoming car of the same mass travelling at the same speed.

In other words, hitting the wall at 42 mph is like driving head-on into another similar car which is also travelling at 42 mph. Not to diminish the accident you had but you can't take your 30 mph and add the other car's 10-15 mph to it and equate it to a 40+mph hit. That's not how the physics works.

Rather than the total, it's the average of the two cars' speeds, assuming equal mass.

Ignoring the differences in mass (I assume your car was heavier, which would skew things a bit more in your favor), if you were going 30 and the other car was going 15, your impact was the equivalent of hitting a wall at 22.5 mph. If he was going 10, it was the equivalent of 20 mph.

Don't get me wrong, that's a big hit, but if your car crushed by the same 1-foot I've assumed for Earnhart's car, and it weighed 3,500 lbs (a guess), your effective impact was 29.6 tons / 3,500 lbs = 16.9g. A little less than that if you assume the lower speed and even a bit less than that if you had more mass than the other car, but I'm nit-picking. Any of these numbers are more of an impact than I'd want to have, but the worst case scenario is "only" about 28% of Earnhardt's 42 mph, 60g hit.

Double the speed, square the effects, which is pretty much what this works out to.

I agree with you that the hit from the side from Schrader's car was likely a mitigating factor in the end result, but it's really hard to say what might have happened had Earnhardt been wearing a HANS. He might still be dead but my bet is he wouldn't be.

But, we'll never know.

Thanks again for playing.

Scott

7. Larry Danielson02/21/2009 07:15:02 AM

Scott,
You have the math, I was never very good at numbers anyway, LOL. But I do know that it was a hell of an impact.

Keep up the great work, it was informational reading and actually fun, if tragedy can be fun.

I was never a Dale Earnhardt fan, but fully admit he did so much for NASCAR and is greatly missed, by even me.

As for the car I was driving, a junker, Plymouth Horizion, But I am glad that airbag worked!

Thanks for the assistance and reading. This has been great.

Larry

8. TREY05/05/2009 10:36:49 AM

9. richard karl phillips 05/06/2009 07:54:26 AM
Homepage: http://realmanrj@yahoo.com

hey what's up man

10. Ken Brewer03/30/2011 10:13:46 AM
Homepage: http://www.trackpedia.com

Just want to add that there are many different styles of Head and Neck Restraints - they're definitely not one size fits all or one clear-cut best in all situations in the least. A wise driver would evaluate a few of them versus their race seat, side net setup, seat belt setup, their own size & build, the car's window opening, and many other factors before choosing a device.