Quote from Ball Bearing Turbo :

It's completely relevant, at least in theory, in a high bank oval where you could achieve a vector sufficient to black you out. At 9Gs, which is the absurd figure I commented on, even a full lateral acceleration can take you out since having even half of your brain starving for oxygen isn't exactly good for you either last time I heard.

Well yeah I related the direction g-force according to the car not the track.
I hope you didn't get me wrong there. So high banked ovals would produce high vertical forces.

Tbh. I have no idea of the influences of lateral forces on the brain.
I thought so ppl would rather loose their head before going blackout on lateral g-forces.
If that isn't the case they could a least use half of the brain together with the corresponding eye.

Just did a quick bit of research, it appears that moving fowards your brain can handle quite a bit of acceleration for a period of time... and quite a bit less moving backwards possibly due to tissues in your eye being rather sensitive (same reason negative vertical accelerations are poorly tolerated I suppose). I couldn't quickly find anything on sideways accelerations per se

I would say a bit that evolution would have a bit to do why we can handle more G's pressing up against our body, (positive Gs) than which we can handle of forces pulling our bodies down (negative Gs). I mean, consider first that we are constantly under 1G pull, and typically that is downward. When we walk, run, jump or fall we get more than 1G (positive) of force. It is rare when we actually get negative Gs in anything besides man-made vehicles, which in terms of time have been around for a very small slice of time compared to how long humans have been around...

... or it could just be physics, and the fact that not enough blood in your brain is bad.

Not to derail the topic, but...

That's the thing about evolution, if humans were constantly under negative g's from some strange way things worked, maybe if we flew like a bird?, then over the course of a (very) long time we would become less effected from the effects of negative gs. The brain/skull and blood vessels would (again slowly over a long time) change to handle the required situations...

But that is for another topic, so I let this end.

Topic derailed:

That is not how evolution works. There would have to be some sort of mutation in some groups of humans that allow them to withstand high G forces. Then through "natural selection" those who didn't die from the G forces would survive to produce offspring. This all means personal conditioning does not contribute to evolution according to the scientific model of evolution.

Quote from legoflamb :

Topic derailed:

That is not how evolution works. There would have to be some sort of mutation in some groups of humans that allow them to withstand high G forces. Then through "natural selection" those who didn't die from the G forces would survive to produce offspring. This all means personal conditioning does not contribute to evolution according to the scientific model of evolution.

Exactly. The lungfish developed a lung before it went on land, not after. Girly lungfish liked the fact that their man (fish) could be a badass on the beach, and sexed his brains out.

Something random happens. If the happening is beneficial, it tends to stay.

Quote from 5haz :

You can see from Adrian Fernandez's qualifying laps how much faster the CART cars will lap Texas than IRL, three 1.5 mile laps in 70 odd seconds.

http://www.youtube.com/watch?v ... v96Rk&feature=related

Man, he was ****ing flying!

Quote from marsaz :

http://en.wikipedia.org/wiki/Pythagorean_theorem

I used this equation
a and b are vertical and lateral forces and c is the overall force.

edit: i think this is not the actual physical formula to calculate forces. I can't find it. This one only aplies when the forces act at an angle of 90 degrees.

force = mass x (velocity / time)

Quote from tristancliffe :

I could only watch 45 seconds of the video before it annoyed me. MAybe it was enlightening to a moron, but when he started describing speed, mass and track length as forces I gave up...

I was not even paying attention to the announcer.

Quote from tristancliffe :

F1 tends to have fewer high-g corners per track than Indy/Champ/Cart. And F1 uses a lot less track camber (banking) so that lateral G is pretty much the overall G, rather than combining it with vertical G relative to the chassis. Even at 'just' 160mph an F1 car will easily pull 5G purely laterally.

You have a very good point.

---

The second page so far, is just awesome. "sexed his brains out" LMAO!

Quote from Dygear :

force = mass x (velocity / time)

And how would you exactly find the value of combined G forces using this formula?

Quote from tristancliffe :

I could only watch 45 seconds of the video before it annoyed me. MAybe it was enlightening to a moron, but when he started describing speed, mass and track length as forces I gave up...

more importantly
gravity doenst magically increase as you approach texas (some other things you alluded to might decrease quite rapidly thoug)

Quote from MadCat360 :

Shuttle takeoff is 3 G until the main boosters quit. That's the same as an aircraft carrier launch.

nuhuh
maximum acceleration of the shuttle is around 3g which only happens right at the end during orbit insertion when the boosters are long gone and the main fuel tank is nearly empty and (and this is the important bit) light

which is one of the reasons why shuttles are so boring
the titans which produced about 8.5g in the second stage... now thats a rocket

Quote from marsaz :

And how would you exactly find the value of combined G forces using this formula?

same way you did
any 2 vectors at right angles can be combine with pythagoras and acceleration happens to be a vector

Quote from yankman :

Relevant for the state of blackout are only the Gs pulling downwards -> sucking the blood out of the head.

As stated in the report high banking and high speed are the causes.

Gs pulling sideways have afaik no effects on blackouts.

Stunt pilots are able the counter high G-forces by tense up but only for a short amount of time.

Indeed. I watched a few of the Redbull Air Races a few weeks ago and saw that they were tensing up pretty hard for some of the higher G changes. With how much they were straining, I don't think anyone of them, or any of the drivers would be able to keep that up for an entire race.

Also, IIRC, they did speak of a few drivers losing sight in one of their eyes. I'm pretty sure it's not due to lateral G's only, but could it have been the work of both lateral and vertical working together to effect the one eye before the entire brain?

((end)velocity - initial velocity) / time = acceleration

Newton's second law of physics: F=ma
Force = Mass * Acceleration

We already know acceleration - it's roughly 50 ms^2 horizontally and 40 ms^2 vertically. I wasn't speaking about the force mentioned above which is measured in N (newtons). I had G force in mind which is acceleration measured in meters per square second.

Now that I've put some time in researching about it (God, internet is good). The overall acceleration or G force is a simple sum of two vectors



Edit: A and B are VECTORS. 2+2=4 does NOT apply here

Sorry about being slightly off topic but isn't the narrator the Jason Priestley? (famous for being a 25yo teenager in Beverly hills 90210)

Quote from heson :

Sorry about being slightly off topic but isn't the narrator the Jason Priestley? (famous for being a 25yo teenager in Beverly hills 90210)

I think so, he had a short lived racing career too IIRC

http://hyperphysics.phy-astr.gsu.edu/hbase/cf.html#cf2

There's the correct equations.

Assuming a 45 degree bank 5g lateral and 4g vertical (relative to the axis of the drivers spine) gives a cetripetal acceleration of 6.7g or ~ 66m/s^2

Working from the speed they refer to in the video of 370km/h gives a velocity of ~102m/s. Plug that in to the website and it requires a constant radius of ~ 644m to achieve the stated g-forces. Thats clearly a lot larger than the actual radius of the banked section of the track shown in the video so I would have thought that it would be relatively easy to achieve peak g-forces of the figures stated for short durations at even lesser speeds.

So in answer to the original poster, no I don't think it sounds like exageration.

Anyway, at the end of the day blacking out has a lot more to do with the physical fitness of the drivers than the actual g-forces sustained. Most average people would probably black out at half those figures. Specially selected, trained and highly fit fighter pilots can survives nearly 50% higher figures for short peaks.

And here I thought everyone learned about Euclidian vector math by the time they're 16.

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

http://en.wikipedia.org/wiki/High-G_training

Quote from Maelstrom :

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

http://en.wikipedia.org/wiki/High-G_training

"without loss of consciousness" does not mean "without loss of vision." Also that sounds like constant force. Where as on a bumpy racetrack getting 6g spikes is like every cell in your body receiving a "knockout punch" from a boxer.

regarding G's.. a gradual onset up to 5 G's would be enough to help your body adapt to the forces.. (increase hart bpm/ blud preshure) but you would still suffer (have a hard time breathing+sqeezing all your muscles to rise blud press.)
on 9 G's Rapid onset(instantly go from 1 to 9) you will be fine for about 5" then you will "pass out" (G-LOC)air force pilots are trained to handle those forces Centrifuge training pilots that is if sitting on an upright possition

G-LOC means G-force induced Loss Of Consciousness

I believe the Indy cars were hitting near 9G's at Talladega, the main reason they don't race there.

Quote from PMD9409 :

I believe the Indy cars were hitting near 9G's at Talladega, the main reason they don't race there.

I heard that a lot of superspeedways are actually banned by IndyCar

The real issue is the G-forces upon impact when one of these cars fail.

I thought a remember seeing somewhere Ernie Irvin's crash at Michigan(1994 maybe?) which inevitably ended his racing career, generated over 14 G's of force. Of course it was for milliseconds, but that's as long as it would take take to kill a normal person .....

Quote from Maelstrom :

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

http://en.wikipedia.org/wiki/High-G_training

Well there you have it then.

New Indy car design:
- drivers lie completely flat on their backs in the fully-enclosed, windowless cockpit
- driver wears a helmet with a HUD and video display from a roll bar mounted camera (centered instead of offset like the TV cams)
- some small windows may be an option so that the driver can see in case of a malfunction of the video display
- controls are otherwise normal

We'll call it Indy LugeCar.

Quote from Forbin :

Well there you have it then.

New Indy car design:
- drivers lie completely flat on their backs in the fully-enclosed, windowless cockpit
- driver wears a helmet with a HUD and video display from a roll bar mounted camera (centered instead of offset like the TV cams)
- some small windows may be an option so that the driver can see in case of a malfunction of the video display
- controls are otherwise normal

We'll call it Indy LugeCar.

you forgot the possibility of missing the apex and flying off track into a croud that will survive a 240+mph impact.

Quote from Forbin :

Well there you have it then.

New Indy car design:
- drivers lie completely flat on their backs in the fully-enclosed, windowless cockpit
- driver wears a helmet with a HUD and video display from a roll bar mounted camera (centered instead of offset like the TV cams)
- some small windows may be an option so that the driver can see in case of a malfunction of the video display
- controls are otherwise normal

We'll call it Indy LugeCar.

Was not really the point of my post.
It was more a response to the 9 g limits.

Under right condition the human body can take a lot. Up to 50g for a very short time.
Under wrong conditions 3g are enough to knock you down.