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Engineer saves man by crashing into him on purpose

seattletimes.nwsource.com

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Re: Engineer saves man by crashing into him on purpose

#61

Post by sharjeel »

WalterBright wrote: post #54
cryptoz wrote: post #23

This is an incredible story. But I think it's important for everyone to remember the context of who this hero is. He manages the F22 fighter jet program at Boeing. That means that he's in charge of building gigantic killing machines that are only built so that they can be used to kill or threaten to kill human beings. This man did an incredible thing on the road and I'm not trying to diminish that. But he's not a 100…

Without effective weapons, many will die. Nobody picks a fight with someone who can effectively fight back.

Thats why every country should have nuclear weapons. There would be so much deterrance that nobody would go for war!

Re: Engineer saves man by crashing into him on purpose

#62

Post by cabalamat »

hugh3 wrote: post #58
zdw wrote: post #17

Earlier quoted context omitted.

Ah, my bad. I think the I missed the joule/kilojoule conversion in the reference I was using. Thanks for the correction!

Not to rub it in, but this is one of those cases where a bit of intuition will get you a lot further than a calculation. Is it plausible that a 2 ton vehicle travelling at 40 mph is equivalent to 70 kg of TNT? Think about the damage done by a crashing minivan. Enough to bend some metal, maybe even knock down a small brick wall. But a 70 kg TNT bomb would easily blow the car into many pieces. Alternatively, how much f…

> Is it plausible that a 2 ton vehicle travelling at 40 mph is equivalent to 70 kg of TNT?

I helps to know that TNT has roughly one tenth the energy density of petrol (4 MJ/kg v. 40 MJ/kg). If it took 7 kg of fuel just to accelerate a vehicle to 40 mph, vehicles would have to carry vastly more fuel than they do.

Re: Engineer saves man by crashing into him on purpose

#63

Post by suprgeek »

An Engineer who can act on his Gut Feel - when the "gut feel" is really his knowledge and experience coming together, needs to be celebrated. Too often we ignore the people who make meaningful but localized differences, so I am all for this story to hit the national headlines.

Re: Engineer saves man by crashing into him on purpose

#64

Post by danparsonson »

dmoney wrote: post #50
danparsonson wrote: post #13

Earlier quoted context omitted.

That's only really a problem if all that energy is transferred to another object (near) instantaneously - for instance if the vehicle hits a stationary object like a car waiting at an intersection. Colliding at a relative speed of only a few miles per hour and then hitting the brakes allowed Innes to dissipate that energy in a more controlled way. Risky, certainly, but I don't think it's as risky as you think it is.…

You wouldn't have to use a spaceship. "meteorite" means it's already hit the ground. You could just walk over to it, assuming it didn't wipe out all life.

Ah yes, perhaps "asteroid" was the right word? Large piece of rock in space :-)

Re: Engineer saves man by crashing into him on purpose

#65

Post by jeza »

Not wanting to discredit Innes' quick thinking. Though this kind of incident does show the danger of policy favouring roads and more driving over mass transit/public transportation. The greater the number of cars on the road, the greater the odds that someone will have a lapse of concentration, consciousness or make some kind of error. It was lucky that someone was able to intervene in this instance, but in other instances there's nothing much anyone could do. Short of designing cars that stop when the driver is unconscious (trains have had technology to ensure the driver is conscious for some decades now).

Re: Engineer saves man by crashing into him on purpose

#66

Post by points »

viraptor wrote: post #56
points wrote: post #26

Earlier quoted context omitted.

Come on. The risk was very low. 1. Drive infront 2. Match the speed 3. Slowly reduce speed so that the car behind knocks into your back bumper at a relative speed of like 1 mph. Maybe you feel a tiny bump. 4. Apply brakes Yes it's impressive, but I'd be willing to bet it's not that dangerous at all. The very very worst case scenario is that you don't match the speed very well and get rear ended, which is pretty much…

Ways this could fail: - breaks are not even across the wheels, he spins and goes right back into the traffic, guy behind falls over after driving the other way into the barrier - collision affects one of the front wheels of the car behind, that car turns into the traffic - minivan either separates or gets locked due to collision - engine in minivan stalls after collision, break assist stop working, simply pressing th…

You still seem to be missing the point that the impact velocity is like If it looks like it's not going to work, you just speed up again...

Re: Engineer saves man by crashing into him on purpose

#67

Post by Tichy »

jeza wrote: post #65

Not wanting to discredit Innes' quick thinking. Though this kind of incident does show the danger of policy favouring roads and more driving over mass transit/public transportation. The greater the number of cars on the road, the greater the odds that someone will have a lapse of concentration, consciousness or make some kind of error. It was lucky that someone was able to intervene in this instance, but in other ins…

That's why I don't like driving: because it is other people's mistakes that can destroy my life.

Re: Engineer saves man by crashing into him on purpose

#68

Post by adolph »

points wrote: post #26
enanoretozon wrote: post #5

Earlier quoted context omitted.

not to mention "Without consulting the passengers in his minivan — "there was no time to take a vote" — Innes kicked into engineer mode." more like "Innes kicked into irresponsible mode risking other people's lives to try something he probably saw on a movie"

Come on. The risk was very low. 1. Drive infront 2. Match the speed 3. Slowly reduce speed so that the car behind knocks into your back bumper at a relative speed of like 1 mph. Maybe you feel a tiny bump. 4. Apply brakes Yes it's impressive, but I'd be willing to bet it's not that dangerous at all. The very very worst case scenario is that you don't match the speed very well and get rear ended, which is pretty much…

I think I remember this being done on an episode of CHiPS.

Don't laugh: I learned how to shift w/o a working clutch from an article in Motor Trend and it came in handy one day.

Re: Engineer saves man by crashing into him on purpose

#69

Post by jonhendry »

Tichy wrote: post #67
jeza wrote: post #65

Not wanting to discredit Innes' quick thinking. Though this kind of incident does show the danger of policy favouring roads and more driving over mass transit/public transportation. The greater the number of cars on the road, the greater the odds that someone will have a lapse of concentration, consciousness or make some kind of error. It was lucky that someone was able to intervene in this instance, but in other ins…

That's why I don't like driving: because it is other people's mistakes that can destroy my life.

On mass transit, you only have to watch out for the nutters who shove people in front of oncoming trains. :)

(I'm a big fan of public transit, and use it every day. But I always look around me when the train is approaching, or get my back to the wall.)

Re: Engineer saves man by crashing into him on purpose

#70

Post by Dove »

astrofinch wrote: post #32

I don't understand how this worked. If Pace's foot was still on the accelerator, wouldn't it be difficult to get his truck to slow down?

Consider that most the acceleration you can possibly exert is the friction between your tires and the road. Consider that your brakes are almost always powerful enough to hit that max (and more -- you can induce a skid). Consider that your engine sometimes is powerful enough to hit that max, but it usually isn't, especially at high speed.

Consider some advice from my driver's ed teacher long ago: "Some folks may have 4 wheel drive, but everybody has 4 wheel stop."

So we have two vehicles duking it out high speed (where braking power >> acceleration power already). It's probably no contest. But at worst, it's a high mass minivan with 4 wheels saying "stop" in a friction-with-the-pavement contest with a medium mass pickup with (probably) 2 wheels saying "go".

The minivan should win handily. Even if the pickup has it floored the whole time.

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