Action Comics #479, Superman comes in at about mach 6 on a decommissioned air strip in Singapore and does a low-in fly-over scraping his face against the tarmac to lose that shadow...

Fine, fine. Cheetah on tarmac, atom on grass, bunnies on both, GO!

Well yeah, but if a cheetah were to try running on tarmac, I doubt it could accelerate as fast normal

A quote I found in regards to this is:

This is Dean Evans at one of the world's most challenging race tracks at Bathurst in Australia. The conditions are a bit damp, and the other drivers are hesitant to get off the racing line and try the grip there. Dean isn't. He goes for it and the results are impressive.

Anyone from moose country knows that you NEVER swerve for an animal, anyway. You pile on the brakes and take the impact. Swerving like that either puts you into oncoming traffic, or the soft shoulder, and compounds the problem.

And incidentally, the Grand Cherokee is an off-road truck. The Touareg and its ilk are/were designed as upsized, slightly more capable cars. The Jeep will fare worse on the tarmac because of its origins. The test isn't really apples to apples.

>> ^CaptainPlanet:

as maestro has astutely pointed out, you've errantly assumed this truck can full stop in zero time. Hurp de durp de durpidy pthhhhhhhhhhh
>> ^Jinx:
>> ^maestro156:
Seems likely to me that he'd be able to brake faster than the truck could break, and if the truck started pulling too far away leaving him exposed, he could coast on the shoulder till he can safely stop.
I'm not saying I would do this, but it doesn't seem all that dangerous. I guess the one thing to worry about would be road debris, since he can't see it coming.

I dont think its about who can stop the fastest, its about how fast you can start stopping.
He's about half a metre away from the back of that truck. He's doing 90kph. Human reaction time is about .2 of a second. Lets do the maths.
90,000m/3600s = 25m/s
25m/s 0.2s = 5m
He's going to travel 5 metres before he even starts slowing down. If that truck has to brake hard he will go into the back of it. Granted, his speed relative to the truck won't be very high but it would prolly be enough to send him arse over tit. at close to 90kph. and he aint exactly in leathers.
I'm not even sure he could stop faster than the truck. Sure, the truck is heavier, but it has 4 wheels, big thick tyres and a lower centre of gravity. Lets do the maths.
The coefficient of friction between road bike tyres and average russian tarmac is...no I kid.


No I didn't? I just assumed the truck would slow enough that he could go into the back of it. So ok, the truck travels 4.8ms, the bike travels 5m. He's now 30cms from the back of the truck, and only now is he gonna start braking. Assuming they decelerate about the same, and I'm not even sure you can stop faster than a truck on a bike, there is still a 3m/s difference in speed with 30cms of room between them. Like I said before, he won't be going very vast relative to the truck when he collides, but his wheels are still going to be spinning prty quickly and I'd guess that would be enough to put him on the pavement...or you know, the risk is large enough that I wouldn't want to try it.


And this is ignoring all the myriad other risks from travelling at 90kph blind. Maybe his attention is on somebody in a car with a video camera in the lane next to him, and suddenly his reaction to the truck braking is delayed...maybe a pothole appears under the truck. Or a puddle. I'd rather base jump than do that.

as maestro has astutely pointed out, you've errantly assumed this truck can full stop in zero time. Hurp de durp de durpidy pthhhhhhhhhhh

>> ^Jinx:

>> ^maestro156:
Seems likely to me that he'd be able to brake faster than the truck could break, and if the truck started pulling too far away leaving him exposed, he could coast on the shoulder till he can safely stop.
I'm not saying I would do this, but it doesn't seem all that dangerous. I guess the one thing to worry about would be road debris, since he can't see it coming.

I dont think its about who can stop the fastest, its about how fast you can start stopping.
He's about half a metre away from the back of that truck. He's doing 90kph. Human reaction time is about .2 of a second. Lets do the maths.
90,000m/3600s = 25m/s
25m/s 0.2s = 5m
He's going to travel 5 metres before he even starts slowing down. If that truck has to brake hard he will go into the back of it. Granted, his speed relative to the truck won't be very high but it would prolly be enough to send him arse over tit. at close to 90kph. and he aint exactly in leathers.
I'm not even sure he could stop faster than the truck. Sure, the truck is heavier, but it has 4 wheels, big thick tyres and a lower centre of gravity. Lets do the maths.
The coefficient of friction between road bike tyres and average russian tarmac is...no I kid.

>> ^maestro156:

Seems likely to me that he'd be able to brake faster than the truck could break, and if the truck started pulling too far away leaving him exposed, he could coast on the shoulder till he can safely stop.
I'm not saying I would do this, but it doesn't seem all that dangerous. I guess the one thing to worry about would be road debris, since he can't see it coming.

I dont think its about who can stop the fastest, its about how fast you can start stopping.

He's about half a metre away from the back of that truck. He's doing 90kph. Human reaction time is about .2 of a second. Lets do the maths.

90,000m/3600s = 25m/s
25m/s*0.2s = 5m

He's going to travel 5 metres before he even starts slowing down. If that truck has to brake hard he will go into the back of it. Granted, his speed relative to the truck won't be very high but it would prolly be enough to send him arse over tit. at close to 90kph. and he aint exactly in leathers.

I'm not even sure he could stop faster than the truck. Sure, the truck is heavier, but it has 4 wheels, big thick tyres and a lower centre of gravity. Lets do the maths.

The coefficient of friction between road bike tyres and average russian tarmac is...no I kid.

Back in '88 I got to be on the tarmac at an airforce base under a space shuttle strapped to a 747. If you have not seen it you can not imagine how massive that combination is.

First rule of racing: NEVER STOP!

You always obey the flags that the marshals hold out, as they are under race control so will know about everything that is happening, not just in the 6 feet of tarmac you are on. Should you stop, you become a target for the next guy leaping through the wall of fire. Now you have two accidents...

There is no flag to stop competitors either. A red flag means that the *race* has been stopped, but that doesn't mean that you actually stop riding. You reduce your speed and await further instructions, being prepared to stop on the circuit *if* directed to do so. Marshals are posted within sighting distance of each other, so someone would have seen it and been able to deal with it.

Ultimately, this guy was through so quickly that even trying to stop would have covered a big distance (at 150mph+) so going back to help wouldn't have made much difference. As a rider you're probably not trained in first aid either, so it's best left to the professionals. On my first race out I couldn't even keep count of the number of laps I had done as I was concentrating so hard on riding as fast as possible!

Personally I'm surprised he slowed down as much as he did...

>> ^Yogi:

That's cool...but why doesn't he stop?! At least to tell some of the orange jackets that there's been a horrible crash!

>> ^Hybrid:

Passenger sitting in big A380: "Did we just hit a little bump?"


That's overstating it. I saw this on the news yesterday, and they said the passengers thought the plane hit a rough spot on the tarmac and then wondered why they were stopping.

"Bored Nasa Employees fill their time forming the shape of a giant cock and bollocks on the tarmac. There sure hasn't been much to do after Discovery landed."

Well, I imagine that water provides a lot more friction than tarmac assuming you aren't water planing over the top of it. They probably pull more G's than most race cars...

>> ^quantumushroom:

Rolling down into Death Valley after about 16,500 miles on the road.
This is the safest way to go down a hill on a Pennyfarthing, as when you have the accident you go feet rather than face first onto the tarmac.
I completed the round the world journey in November 2008 after 2 1/2 years, 22,000 miles on the road, and having visited 25 countries.
www.pennyfarthingworldtour.com
Joff
Yeah, landing on your feet will be much safer, at least before the first 3 flips.


I think I would trust the dude who rode 22,000 miles on the thing rather than people who have never seen one, like, um, us.