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Model X in fatal wrong way driver crash today in Phoenix?
- Thread starter azred
- Start date
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- Driving Dynamics Model X
During an evacuation where the authorities are sending people down both sides to increase flow.
Tam
Well-Known Member
Lane Reversal has been quite very common in evacuations.
I-26 eastbound reversal begins; what you need to know
Evacuation Routes
Established contraflow as a plan:
http://www.sctraffic.org/pdf/US501.pdf
brucet999
Active Member
Head-on collision impact of two equal-weight vehicles at 75mph is equivalent to one vehicle colliding with a concrete bridge post at 75 mph; both cases result in deceleration from 75mph to zero in about 0.05 second.
When vehicle mass is different, the larger one decelerates slower and the smaller one faster, so the 3,000lb car might experience equivalent of 125mph collision with an unyielding concrete bridge post.
Xenoilphobe
Well-Known Member
Damn that is a brutal accident - in my 34 years of driving I have only had two close calls - and both were elderly folks (both on Sunday) driving the wrong way on a divided highway - most terrifying event ever driving - I can't imagine what that impact was like.
Peace to the families, hug the survivors and realize this could happen to any of us. Cherish every day - cause it could all end tomorrow.
Peace to the families, hug the survivors and realize this could happen to any of us. Cherish every day - cause it could all end tomorrow.
Nosken
Active Member
Somewhat de-bunking bigger is better. In most two vehicle crashes yes. Single vehicle not as much. Of course with the Tesla, we can rule out their statistics regarding roll over and have your vehicles. I have a research this a lot, but I remember reading somewhere, this is probably not the best article.
Myth Busted – Larger, Heavier Vehicles Are Not Necessarily Safer
Myth Busted – Larger, Heavier Vehicles Are Not Necessarily Safer
Brando
Active Member
Isn't deceleration directly related to the distance and speed - i.e. length of the crumple zone?
Energy is no doubt related to the mass - which would help explain the wreckage, I suppose.
How did you come up with the 0.05 seconds? theory or actual data?
Sorry, you confused me. Two different massed cars (one 3000# the other unknown) and then compare to stationary bridge post crash. Seems a rather difficult transformation. Doesn't really matter that much. You really don't want to experience such a wreck. Maybe not even witness.
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For what it is worth, this seems to be the closest off-ramp where the car could have entered the wrong way:
If he didn't go left (the wrong way) on that first left arrow, there is a second chance to get confused and make a mistake:
I think that looks fairly confusing actually. Both lanes are supposed to go over the freeway and turn left to go north.
If you follow the red path you are going into head on traffic.
If there was no one on the off-ramp it wouldn't be totally obvious that it is an exit.
(Yes, once you are on the off-ramp, there is a small "one-way", small "do not enter" and small "wrong-way" so some lack of attention does seem to be a factor as well...)
I think the overall design could lead to confusion... You see the first ramp and think "south exit", and you see the second ramp and think "north entrance". The actual north entrance is the 3rd ramp off in the distance well past the left turn arrows. The "101 North" sign is right before the 101 South exit.
If he didn't go left (the wrong way) on that first left arrow, there is a second chance to get confused and make a mistake:
I think that looks fairly confusing actually. Both lanes are supposed to go over the freeway and turn left to go north.
If you follow the red path you are going into head on traffic.
If there was no one on the off-ramp it wouldn't be totally obvious that it is an exit.
(Yes, once you are on the off-ramp, there is a small "one-way", small "do not enter" and small "wrong-way" so some lack of attention does seem to be a factor as well...)
I think the overall design could lead to confusion... You see the first ramp and think "south exit", and you see the second ramp and think "north entrance". The actual north entrance is the 3rd ramp off in the distance well past the left turn arrows. The "101 North" sign is right before the 101 South exit.
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SomeJoe7777
Marginally-Known Member
That intersection is a SPUI (single-point urban exchange), a relatively new intersection design. It's confusing for those people who have never seen one. It has the advantage in that it moves traffic faster that a typical freeway/cross street intersection that has to use two traffic lights on either side of the freeway. The SPUI reduces the intersection to a single traffic light.
If it was night, you were unfamiliar with the intersection, and there were no other cars at the intersection to give you visual cues to traffic flow, it would be very easy to enter the wrong ramp. Since there are no service roads on this freeway, going into the incorrect ramp will lead you directly onto the freeway going the wrong direction.
Here's an overhead view of the 101 / Catcus road SPUI intersection:
If it was night, you were unfamiliar with the intersection, and there were no other cars at the intersection to give you visual cues to traffic flow, it would be very easy to enter the wrong ramp. Since there are no service roads on this freeway, going into the incorrect ramp will lead you directly onto the freeway going the wrong direction.
Here's an overhead view of the 101 / Catcus road SPUI intersection:
Those turn arrows painted on the road are misleading. They show a 90 degree turn when you really want to do more like a gradual 45 degree sweeping turn.
They are trying to give you hints with the dotted lines, but those aren't very noticeable, particularly at night, and they are worn down in the most important place.
They are trying to give you hints with the dotted lines, but those aren't very noticeable, particularly at night, and they are worn down in the most important place.
Seems like they should have a "Do Not Enter" sign right here:
brucet999
Active Member
Right. Deceleration is the same from collision of two cars of equal mass at equal speed as with one car crashing into an immovable object like a concrete freeway bridge pillar. At 75 mph a car is traveling 110 ft/sec, so assuming a 6 ft crumple zone, the car stops in 6/110 = 0.054 seconds.
In the case of two cars of unequal mass, then the heavier one stops slightly more gradually and the smaller one quicker because the heavy car has more momentum. Imagine, if you will, the collision of two football players at the same speed. The heavier one will drive the lighter one a little ways backward.
I guess alcohol is a bigger problem in the US. Here in Norway, it's almost always older people who end up going the wrong way on the motorway.We have had hundreds in metro Phoenix and according to ADOT the incidents usually happen late at night. ADOT says alcohol use and milennials are the most common characteristics.
I'm sure you also have this challenge with older drivers, but I can understand if it drowns in the number of alcohol related incidents. We don't mess around with drunk driving, though. The limit is 0.02%. If you have more than 0.05%, you lose your license for at least a year. More than 0.12% and you lose it for 2-5 years and risk prison for up to a year (minimum 21 days). Also a fine of 1.5 months income for all drunk driving.
One thing that's very odd for people going to the US from Norway is that people drink and drive. You don't do that in Norway, even if it is just one drink.
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Candleflame
Active Member
They are there:
The only thing I've seen is that they "didn't seem" life threatening.
I've seen these very effectively in action in Colorado Springs.
Instead of just repainting those lines. . . save a life for minor $$.
LaneLight | LED Enhanced Warning Systems
Traffic and Parking Control Products and Solutions | Traffic & Parking Control Co., Inc.
Anybody know someone at Phoenix Road Department? (or maybe the TV News people)
Instead of just repainting those lines. . . save a life for minor $$.
LaneLight | LED Enhanced Warning Systems
Traffic and Parking Control Products and Solutions | Traffic & Parking Control Co., Inc.
Anybody know someone at Phoenix Road Department? (or maybe the TV News people)
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Lack of training has something to do with it. If the reflectors on the road are red STOP!!!.
The backside of freeway reflectors have been red for many decades. This warns you that you are going in the wrong direction.
But the crash itself does say something about small-offset impact testing.
The backside of freeway reflectors have been red for many decades. This warns you that you are going in the wrong direction.
But the crash itself does say something about small-offset impact testing.
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