I'm not rocket sceintist but I do fly planes and I also know that in a car wreck when a car croses the center line into on coming traffic that the other cars are moving too. This will change your math alot so your test is not accurate at least mythbusters doesn't just wimp out on the science part and make huge assumptions. Cancel the show and leave it to the busters.
I agree. Anyone who did Physics will remember the forces involved, and their math seems way off.
The biggest problem I see is with the smashing the cars into the wall for the arrestor concrete is that the wall they were smashing into wasn't even nailed down into the parking lot. How many highways do you know that just set the barriers in the middle?
Also, the big pad, if you look at what's on the runway, they bed at the end of the runway is in a grid, and secured, with something greater than cheap wood.
They really need to rethink some of this and put some real math and science into it.
(also, what did they think it was going to happen when they hit a ramp at 60mph? it wasn't going to go airborne?)
i totally agree, ive only taken highschool physics and i could figure out the actual speed that the cars are hitting. its just a little pathetic that a group of engineers and scientists cant. if you cant do it right just let the mythbusters do it.
They did take the wrong approach here. I am watching the episode right now, and the part where the run the car over the cement expectin it to sink just wont work due to the body of the car. the difference between a car and plane is that the car has suspension thats alot crazier then a plane. so thus the car will just keep on bouncing back up to the surface of the cement. Im not done the episode yet but if my views change i will post it up.
Edit: Finished the show and now mythbusters on.....yea they should learn a few things from good ol' busters.
Linkero, I'm with you. An Airplane has a HUGE amount of weight and force displaced on 3-7 (747?) landing gears, while a car has a much smaller weight to wheel ratio. And you saw the suspension just bounce over the surface of the concrete.
Her whole comment (just now) about the density of the arrestor bed is right on, she should have used the 40% Air to cement ratio.
I havent taken any formal science classes or anything, and i figured out that the crapping concrete laying they did wast going to work. so maybe discovery would give me a job?
Exactly. If the cement would of crumbled right under the car then they coulda hoped that the body would go under the cement some and probably catched and come to a stop. Other then that they have to go back to thier lab and get a few books out and do more studying
If cars can hydroplane on WATER what makes them think that their concrete bed would do any good.
BEST CASE stopping scenario for that would have been trying a bed of GRAVEL... that's about all it COULD have done... assuming it was implemented properly to begin with...
First off, the objective was to stop a car, not a bus. How many buses are going wild on the highway compared to cars? We'll let that slide for now.
As for the experiment itself, the bus was only stopped because the arrestor bed was uneven, causing the bus to bounce. If you notice, the bus doesn't have problems until this bouncing reaches a critical level. If the bed was done properly, the bus would have replicated the car.
Finally, this would never be a feasible option in real life: pouring that much concrete is not effective enough to justify the economics, any use of it would require a whole new pouring, and if a car were to clip the bed on accident, it would be sent into a crash (which is what we were trying to avoid).
I watched this show with 3 other engineers and cringed continually...
I honestly signed up for Discovery.com just to complain about Smash Lab's most recent cement show. Does anyone else think the girl's voice on the show is extremely irritating? I nearly wanted to change the channel everytime she spoke.
It is obvious they know nothing about concrete, I have been working with this stuff for the past 20 yrs, either batching it or laying it on the ground.
They should just keep this on the airfields and not even worry about the highways for a few more decades. no matter what they do to a highway there will still be a large amount of accidents and fatalities
That comment about gravel is more than correct. Look at run away truck shut down lanes. They either run up hill or into a pit that tapers 4-6 feet deep, filled with loose gravel. I do not know how long it takes to stop the a semi traveling at 60 mph but it stops it. If someone was to spend the money to line the road with concrete, they would be better off to use gravel.
On top of all the other errors mentioned, they only used 1 car (Ford Crown Vic) for all their tests which weighs close to 4,000 lbs (one of the few accurate things mentioned). What if a sub 2,000 lb car like a Lotus Elise/Exige were to smack into one of those walls or on that bed? Even better is the fact that auto racing is already using safer barriers to decrease the force of impact of cars traveling at 180+ mph. Basically this show shows absolutely no science and the hosts just seem like total tools and don't know anymore than a kid who graduated high school.
TINGS13 Im with you i just spent 10 minutes during the show-not like i was missing a whole lot-signing up with discovery to complain about this show. that wench is about as annoying as dog s@%t on the bottom of ur shoe. the whole time i was contiplating a myth they could bust on how much g force it would take to put a bullet into her head hopefully this annoying show gets taken off the air in a couple months so we dont have to see the annoying commericals for their new episodes
Clearly a mythbusters rip off but aside from that. If what they are testing is actually practical in anyway don't you think someone with a little more time/experience would have come up with it? Having an extremely large pad of soft concrete which might have stopped a bus but not a car in between oncoming traffic on any highway isn't even close to practical.
They aren't even applying the scientific method properly. As far as I could tell the initial crash had nothing to do with their tests. For the standard barrier with soft concrete in front of it they didn't even test the barrier without anything in front to compare.
