Paul Walker Died Today
#126
MBWorld Fanatic!
Joined: Jan 2008
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From: Naperville, IL/Chicago
2008 CLK63 Black Series 2012 C63 Black Series 2014 SLS Black Series
that is once the brakes are applied
reaction time and system lag time (pedal travel, build up some prssure, pads to engage)
the numbers I've seen for Porsches with PCCB were 310 range
couldn't find a specific number for the CGT and this is under testing conditions: on a wet or road with any debris, paint stripes, worn tires, etc, you will be much further...a couple 32's of tire wear can increase the distance significantly, as much as 20% according to Bosch Automotive Engineering Handbook...
reaction time, even if you can assess the situation/need to brake and make the move in 1 sec, unlikely, you still have travelled 150 ft
even if it's only 2 seconds to see a deer, kid, stopped vehicle you'll have travelled 300'
trained gun fighters require that much to assess and fire, and they are locked and loaded and anticipating the shot...
'surpise' adds a lot to reaction time, you don't drive on the edge of anticpation of emergency/unexpected braking (like you do when you know a corner is approaching)
according to Bosch and Volvo the system lag may be 0.1 to 0.3 sec, 15 to 45 ft
500' for the total distance = reaction + system lag + braking distance is not unrealistic, and probably conservative
from a highway design manual
To make highways reasonably safe, the engineer must provide a continuous sight distance (see the stopping sight distance module) equal to or greater than the stopping sight distance. As an integral part of the stopping sight distance, a value for the brake reaction time must be assumed. Extensive research has shown that 90% of the driving population can react in 2.5 seconds or less. The brake reaction time normally used in design, therefore, is 2.5 seconds. The distance traveled during the brake reaction time can be calculated by multiplying the vehicle's initial speed by the brake reaction time.
on a bell curve 80% will be 2 sec +/- 0.1 sec
Here's a simple example. Suppose a person is driving a car at 55 mph (80.67 feet/sec) during the day on a dry, level road. He sees a pedestrian and applies the brakes. What is the shortest stopping distance that can reasonably be expected? Total stopping distance consists of three components:
reaction time and system lag time (pedal travel, build up some prssure, pads to engage)
the numbers I've seen for Porsches with PCCB were 310 range
couldn't find a specific number for the CGT and this is under testing conditions: on a wet or road with any debris, paint stripes, worn tires, etc, you will be much further...a couple 32's of tire wear can increase the distance significantly, as much as 20% according to Bosch Automotive Engineering Handbook...
reaction time, even if you can assess the situation/need to brake and make the move in 1 sec, unlikely, you still have travelled 150 ft
even if it's only 2 seconds to see a deer, kid, stopped vehicle you'll have travelled 300'
trained gun fighters require that much to assess and fire, and they are locked and loaded and anticipating the shot...
'surpise' adds a lot to reaction time, you don't drive on the edge of anticpation of emergency/unexpected braking (like you do when you know a corner is approaching)
according to Bosch and Volvo the system lag may be 0.1 to 0.3 sec, 15 to 45 ft
500' for the total distance = reaction + system lag + braking distance is not unrealistic, and probably conservative
from a highway design manual
To make highways reasonably safe, the engineer must provide a continuous sight distance (see the stopping sight distance module) equal to or greater than the stopping sight distance. As an integral part of the stopping sight distance, a value for the brake reaction time must be assumed. Extensive research has shown that 90% of the driving population can react in 2.5 seconds or less. The brake reaction time normally used in design, therefore, is 2.5 seconds. The distance traveled during the brake reaction time can be calculated by multiplying the vehicle's initial speed by the brake reaction time.
on a bell curve 80% will be 2 sec +/- 0.1 sec
Here's a simple example. Suppose a person is driving a car at 55 mph (80.67 feet/sec) during the day on a dry, level road. He sees a pedestrian and applies the brakes. What is the shortest stopping distance that can reasonably be expected? Total stopping distance consists of three components:
- Reaction Distance. First. Suppose the reaction time is 1.5 seconds. This means that the car will travel 1.5 x80.67 or 120.9 feet before the brakes are even applied.
- Brake Engagement Distance. Most reaction time studies consider the response completed at the moment the foot touches the brake pedal. However, brakes do not engage instantaneously. There is an additional time required for the pedal to depress and for the brakes to engage. This is variable and difficult to summarize in a single number because it depends on urgency and braking style. In an emergency, a reasonable estimate is .3 second, adding another 24.2 feet.
- Physical Force Distance. Once the brakes engage, the stopping distance is determined by physical forces (D=S²/(30*f) where S is mph) as 134.4 feet.
Last edited by jrcart; 01-05-2014 at 06:18 PM.
#127
#128
#129
you probably think anybody trying to explain anything to your superior brain is 'condescending'
saying it's stupid to travel >100 mph in a business park and hitting concrete poles doens't seem to get thru to people like you...
most are not smart enough to realize the consequences of their actions
and this was supposedly a racecar driver
#130
"Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe."
so you're an electrical engineer?
I doubt it
a EE would use j rather than i (what's 'a'?)
Last edited by Ingenieur; 01-05-2014 at 09:33 PM.
#131
what is that ahead?
what should I do? (nothing, brake, swerve, etc.)
then the physical reaction time to implement the decison, make the move
then the system lag/delay and actual stopping distance
it's a loooong way but a short time
I'm as guilty as anyone of thinking my skills are better than they are...
people have a hard time embracing their limitations
so I try to compensate with a better understanding of the physics/mechanics of the system
travelling in a car at >100 mph is a potentially dangerous situation and many lose sight of this due to complacency or having gotten away with it before, or vodeo games, or movies,whatever...some people are easily influenced
these guys had everything to live for, yet died in the blink of the eye for nothing...tragic
completely & easily avoidable
hopefully some good can come from this, perhaps young guys who see this accident rethink their driving style on public streets, I don't know the guy (obviously), but I think Walker would like this, it could save lives, then it could have some meaning
Last edited by Ingenieur; 01-05-2014 at 10:05 PM.
#132
http://i.cdn.turner.com/dr/teg/tsg/r...paulwalker.pdf
mentions multiple pelvic fractures....thats the big one also, massive blood loss ----> death....if it wasnt for the fire
report mentions that the fracture ends show charring...ok yeah thats heat related...likely had open fractures secondary to the impact and then his bones got burnt
mentions multiple pelvic fractures....thats the big one also, massive blood loss ----> death....if it wasnt for the fire
report mentions that the fracture ends show charring...ok yeah thats heat related...likely had open fractures secondary to the impact and then his bones got burnt
Last edited by vdubpower; 01-05-2014 at 10:21 PM.
#133
Member
Joined: Jan 2014
Posts: 157
Likes: 3
From: Atlanta, GA
2008 C63, 2008 ML550, 2014 KTM 500 XC W, John Deere 990
you need to be like that when trying to convey even the most basic information to morons like yourself, especially when they get verbose trying to sound intelligent mr. look at me I'm a 'math man'
you probably think anybody trying to explain anything to your superior brain is 'condescending'
you probably think anybody trying to explain anything to your superior brain is 'condescending'
#135
Member
Joined: Feb 2008
Posts: 124
Likes: 0
From: Lake Forest, IL
08 CLK63 Black Series, 11 ZR1, 13 M6, 15 G63
To think it is only early January and we already have a Douchebag Of The Year contender
#136
#137
What happened to "Z" in your Signature quote?
some decisons need made before any action can be initiated:
what is that ahead?
what should I do? (nothing, brake, swerve, etc.)
then the physical reaction time to implement the decison, make the move
then the system lag/delay and actual stopping distance
it's a loooong way but a short time
I'm as guilty as anyone of thinking my skills are better than they are...
people have a hard time embracing their limitations
so I try to compensate with a better understanding of the physics/mechanics of the system
travelling in a car at >100 mph is a potentially dangerous situation and many lose sight of this due to complacency or having gotten away with it before, or vodeo games, or movies,whatever...some people are easily influenced
these guys had everything to live for, yet died in the blink of the eye for nothing...tragic
completely & easily avoidable
hopefully some good can come from this, perhaps young guys who see this accident rethink their driving style on public streets, I don't know the guy (obviously), but I think Walker would like this, it could save lives, then it could have some meaning
what is that ahead?
what should I do? (nothing, brake, swerve, etc.)
then the physical reaction time to implement the decison, make the move
then the system lag/delay and actual stopping distance
it's a loooong way but a short time
I'm as guilty as anyone of thinking my skills are better than they are...
people have a hard time embracing their limitations
so I try to compensate with a better understanding of the physics/mechanics of the system
travelling in a car at >100 mph is a potentially dangerous situation and many lose sight of this due to complacency or having gotten away with it before, or vodeo games, or movies,whatever...some people are easily influenced
these guys had everything to live for, yet died in the blink of the eye for nothing...tragic
completely & easily avoidable
hopefully some good can come from this, perhaps young guys who see this accident rethink their driving style on public streets, I don't know the guy (obviously), but I think Walker would like this, it could save lives, then it could have some meaning
"If A is a success in life, then A equals x plus y plus z. Work is x; y is play; and z is keeping your mouth shut."
Last edited by Thericker; 01-06-2014 at 05:56 PM.
#138
#140
heck, he's ruined one of the sticky already last year. https://mbworld.org/forums/c63-amg-w...oblems-21.html
I was not the first person to attack
I present fact based information contrary to the lemming and the sky is falling mentality, so I become a target
get your facts straight skippy
#141
#142
here's the report http://i.cdn.turner.com/dr/teg/tsg/r...paulwalker.pdf
this guy was like a past generations Paul Newman (although not 1/2 the actor as Newman, he had the 'cool' factor), hopefully it will make some street racer have second thoughts whne the stupid urge comes over him
this guy was like a past generations Paul Newman (although not 1/2 the actor as Newman, he had the 'cool' factor), hopefully it will make some street racer have second thoughts whne the stupid urge comes over him
#143
MBWorld Fanatic!
Joined: Jan 2008
Posts: 6,621
Likes: 54
From: Naperville, IL/Chicago
2008 CLK63 Black Series 2012 C63 Black Series 2014 SLS Black Series
He is far from being a D bag. Actually he is a real engineer and pro nhra drag racer, pretty sure he was involved on designing the 1990's Corvette ZR1 motor for Mercury Marine, I am also pretty sure his family founded Mercury Marine and he still heads up their engineering department, just sayin.
Last edited by jrcart; 01-06-2014 at 06:28 PM.
#144
He is far from being a D bag. Actually he is a real engineer and pro nhra drag racer, pretty sure he was involved on designing the 1990's Corvette ZR1 motor for Mercury Marine, I am also pretty sure his family founded Mercury Marine and he still heads up their engineering department, just sayin.
just a smart douche'
#145
MBWorld Fanatic!
Joined: Jan 2008
Posts: 6,621
Likes: 54
From: Naperville, IL/Chicago
2008 CLK63 Black Series 2012 C63 Black Series 2014 SLS Black Series
#146
MBWorld Fanatic!
Joined: Jan 2008
Posts: 6,621
Likes: 54
From: Naperville, IL/Chicago
2008 CLK63 Black Series 2012 C63 Black Series 2014 SLS Black Series
#147
You certainly showed us.. In your pedantic never ending delivery no less.. I feel pitty for anyone in your immediate social circle who's forced to endure regular ear phuking sessions from you. (obviously only family members as you clearly are a terribly lonely bitter friendless human being)
Happy New Year
Happy New Year
#149
You certainly showed us.. In your pedantic never ending delivery no less.. I feel pitty for anyone in your immediate social circle who's forced to endure regular ear phuking sessions from you. (obviously only family members as you clearly are a terribly lonely bitter friendless human being)
Happy New Year
Happy New Year
please don't take it out on those around you
they suffer enough
kick the dog and leave the kids alone