Paul Walker Died Today
01-06-2014, 08:38 PM
#155
Super Member
imagination
01-08-2014, 03:26 PM
#158
MBWorld Fanatic!
yes
walker had soot in his lungs meaning he was breathing smoke/fire for a time
sounds like the driver died quickly, his side sheared the concrete pole almost splitting the car in two, it sounds like his head hit the pole
such a stupid waste of life
people need to realize you need 500' to stop from 100 mph, that is a long way
speeding on secondary roads is absolutely stupid
at least on a divided interstate you have some room for margin of error
none on a secondary road
I think the actual police accident report, ie, cause and specifics of the accident, (vs the coroner report, cause of death, etc.) will show he was travelling closer to 130-150 range, and slowed to 100+ before impact
a damn shame
walker had soot in his lungs meaning he was breathing smoke/fire for a time
sounds like the driver died quickly, his side sheared the concrete pole almost splitting the car in two, it sounds like his head hit the pole
such a stupid waste of life
people need to realize you need 500' to stop from 100 mph, that is a long way
speeding on secondary roads is absolutely stupid
at least on a divided interstate you have some room for margin of error
none on a secondary road
I think the actual police accident report, ie, cause and specifics of the accident, (vs the coroner report, cause of death, etc.) will show he was travelling closer to 130-150 range, and slowed to 100+ before impact
a damn shame
Everything I am reading leads me to believe otherwise... Where did you get this information?
This is what I read.
"The autopsy revealed "scant soot" in Walker's trachea, suggesting his life ended before the smoke and fire engulfed the car."
So unless I'm missing something, the soot was found in the trachea, meaning it never reached the lungs. This information suggests his breathing stopped prior to the fire...
01-08-2014, 03:33 PM
#159
MBWorld Fanatic!
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 Autosport7; 01-08-2014 at 03:35 PM.
01-08-2014, 04:26 PM
#160
MBWorld Fanatic!
I think the point he was trying to make is that people that are not accustumed to traveling at high rates of speed generally do not have good judgment on closing speeds. I raced superbikes for years so it is second nature for me. The first time I raced at Daytona I had the privilage of talking with Mr. Daytona himself Scott Russell. He told me "coming off the banking going through the tri-oval you are going over 185mph at that speed you are traveling at 275 feet per second(nearly a football field a second), brake a half second too late and you will overshoot the corner by 100 ft so timing in that corner is everything". Up until that point I had never really looked at the numbers or physics like that but it made sense and put speed into perspective for me. When you are out there traveling at that speed it does not feel like you are traveling at a football field per second so until someone opens your eyes to that reality it never comes up in your mind, at least it never came up in mine.
01-08-2014, 06:06 PM
#161
MBWorld Fanatic!
He told me "coming off the banking going through the tri-oval you are going over 185mph at that speed you are traveling at 275 feet per second(nearly a football field a second), brake a half second too late and you will overshoot the corner by 100 ft so timing in that corner is everything".
OK... I'll stop
