How Fast Was the Other Vehicle Going to Launch Me 25 Meters in a T-Bone Crash?

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Discussion Overview

The discussion revolves around the circumstances and physics of a T-bone crash involving a motorbike and a van. Participants explore the minimum speed of the van that would have been necessary to launch the motorcyclist approximately 25 meters, considering factors such as vehicle types, distances, and the possibility of the van stopping before the collision.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants question the relevance of whether the van stopped before the collision, arguing that the significant distance the motorcyclist was launched indicates the van was at fault regardless.
  • Others propose that understanding the van's speed and whether it could have accelerated from a stop is crucial to determining fault.
  • One participant mentions the need for specific measurements, including the type of vehicles involved and the distance from the stop sign to the collision point.
  • There is a discussion about the physical evidence of the crash, including the damage to the motorbike and the lack of eyewitness accounts supporting the motorcyclist's claims.
  • Some participants express skepticism about the motorcyclist's ability to prove the van's speed and stopping behavior based on the available evidence.
  • Concerns are raised about the ambiguity of the situation, particularly regarding the police investigation and the potential for differing interpretations of the events leading to the crash.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the relevance of the van's stopping behavior or the implications of the crash dynamics. Multiple competing views remain regarding the interpretation of the evidence and the determination of fault.

Contextual Notes

Limitations include the lack of precise measurements of distances involved, the uncertainty about the exact circumstances of the crash, and the absence of clear eyewitness accounts. The discussion also highlights the complexity of determining fault in traffic accidents based on physical evidence and witness testimony.

chrisso
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hi everybody

i was involved in a crash about a year ago where the driver of the other vehicle t-boned me(me on my motorbike), he tells police that he stopped. i would like to find out what his minimum speed must have been roughly (cos he did send me flying about 25 odd metres). if it's too high then he obviously didnt stop beforehand.

does anyone know where i can find out this sort of thing if i get some measurements and draw a quick drawing?

can somebody help?
 
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What's there to figure out?

a) he hit you (and I assume damaged the bike) and b) you flew 25m through the air.

He clearly didn't stop - that or he's saying your bike damaged itself and you're superman.
 


I assume that your question is two parts:
1) how fast was he going when he hit me in order to throw me 25 m?
2) could he have accelerated from a stop to that speed in the distance between the stop sign and the collision?

What kind of car was it, what kind of bike was it, and how far from the stop sign did the collision occur?

This site talks about collisions with pedestrians. Do you know the distance you slid along the ground after impact, and the type of ground?

http://www.tarorigin.com/art/Lmartinez/Ped/

More directly relevant:
http://www.tarorigin.com/art/Arich/
http://www.tarorigin.com/art/Arich/Ped/
 
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DaleSpam said:
I assume that your question is two parts:
1) how fast was he going when he hit me in order to throw me 25 m?
2) could he have accelerated from a stop to that speed in the distance between the stop sign and the collision?

What kind of car was it, and how far from the stop sign did the collision occur?



exactly right...
 


I still don't see why it is relevant.

He hit you and launched you 25m (bear in mind 25m is ~80ft which makes it one hell of a thump), why does it matter if he stopped or not? He is at fault.
 


DaleSpam said:
What kind of car was it, what kind of bike was it, and how far from the stop sign did the collision occur?

it was on older morel van... I'm sorry i don't know exactly what type of van it was, but i can find out.

see picture: http://www.perthnow.com.au/news/wes...t-smashed-by-van/story-e6frg13u-1225827355392

my bike was a honda cbr600f4 weighing about 170kg plus my weight (which was 123kg at the time of the crash) plus a couple of kilos of riding clothing

i was in the left hand side of the right hand lane, he traveled about the width of one lane so in total it would have been around 5 metres. again i can take exact measurements to find out. and also measurements of how far i traveled after the crash
 
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jarednjames said:
I still don't see why it is relevant.

He hit you and launched you 25m (bear in mind 25m is ~80ft which makes it one hell of a thump), why does it matter if he stopped or not? He is at fault.

correct but the police officer was obviously favouring him.

if i can prove without a doubt that he wasn't physically possible of stopping and accelerating to enough of a speed to send me flying that distance and tear the metal frame apart on my bike then i will be able to get him in a load of trouble...

i just want to do my research on this before i go any further with it
 


chrisso said:
correct but the police officer was obviously favouring him.

Do you have a damaged bike (indicating a severe smash) and witnesses / proof you flew 80ft? If so, he can favour him all he likes. It's irrelevant.
if i can prove without a doubt that he wasn't physically possible of stopping and accelerating to enough of a speed to send me flying that distance and tear the metal frame apart on my bike then i will be able to get him in a load of trouble...

He hit you. Whether he was stopping, accelerating or traveling at a steady speed means nothing.

If the damage is that your bike is a write-off (with that frame damage it sounds very severe) and you were thrown 80ft, what is the argument here?

It's like you are trying to put the nail in the coffin of a cut and dried case (unless there's some detail which you are neglecting to tell us - such as one that puts you in the wrong).
 


DaleSpam said:
This site talks about collisions with pedestrians. Do you know the distance you slid along the ground after impact, and the type of ground?

http://www.tarorigin.com/art/Lmartinez/Ped/

More directly relevant:
http://www.tarorigin.com/art/Arich/
http://www.tarorigin.com/art/Arich/Ped/


sorry i didnt see this part before, i don't think i slid along the ground straight away, i actually was launched from the bike over 3 lanes plus a median strip around another lane width and landed on the grass.
 
  • #10


chrisso said:
sorry i didnt see this part before, i don't think i slid along the ground straight away, i actually was launched from the bike over 3 lanes plus a median strip around another lane width and landed on the grass.

3 lanes plus another lanes width, at approximately 12ft a lane gives a travel distance of around 4x12ft = 48ft.

Not even close to 20m (80ft).
 
  • #11


Major Crash Investigation was called to the scene to investigate who was at fault.
What was the result of the investigation?
 
  • #12


jarednjames said:
3 lanes plus another lanes width, at approximately 12ft a lane gives a travel distance of around 4x12ft = 48ft.

Not even close to 20m (80ft).
Wouldn't some of the 20 meters be in the motorcycle's direction of travel?
 
  • #13


Borg said:
What was the result of the investigation?

I think that is what we're missing and it's the thing I believe says the biker was at fault. Just my opinion, but it does seem that there's something not right here.

The evidence we've been presented with just doesn't add up as to why you'd need to further defend the case.
 
  • #14


jarednjames said:
Do you have a damaged bike (indicating a severe smash) and witnesses / proof you flew 80ft? If so, he can favour him all he likes. It's irrelevant.


He hit you. Whether he was stopping, accelerating or traveling at a steady speed means nothing.

If the damage is that your bike is a write-off (with that frame damage it sounds very severe) and you were thrown 80ft, what is the argument here?

It's like you are trying to put the nail in the coffin of a cut and dried case (unless there's some detail which you are neglecting to tell us - such as one that puts you in the wrong).

unfortunately the lawyer didn't sound so positive, plus i had to state to the insurance commission that he didn't stop. i do agree with you, and i wish it was so clear. however it isn't.

hence why I'm doing my own research to prove that he didnt.

there was a witness that said they "heard" me speeding, but with an akropovic full exhaust system on it was incredibly loud.

but no witnesses that actually saw anything.. i don't think;.
 
  • #15


jarednjames said:
I still don't see why it is relevant.

He hit you and launched you 25m (bear in mind 25m is ~80ft which makes it one hell of a thump), why does it matter if he stopped or not? He is at fault.

The issue here is whether he stopped at the stop sign then accelerated into the intersection or whether he just blew through the stop sign.

In the latter case, the driver is most definitely at fault for failing to stop at a stop sign. In the former case, there is considerably more grey area in how much he is at fault, it not even clear who had right of way.

If the driver diligently stopped the stop sign, then pulled forward having right-of-way, and then Chrisso blew through his stop sign, then the driver is not at fault.

See?
 
  • #16


jarednjames said:
3 lanes plus another lanes width, at approximately 12ft a lane gives a travel distance of around 4x12ft = 48ft.

Not even close to 20m (80ft).

jj, there's no way to calculate this in a vacuum of facts. You have no idea how wide the lanes are, or the sidewalk, no idea how far into the grass he went, or how far down the street on his own path he went.
 
  • #17


DaveC426913 said:
The issue here is whether he stopped at the stop sign then accelerated into the intersection or whether he just blew through the stop sign.

In the latter case, the driver is most definitely at fault for failing to stop at a stop sign. In the former case, there is considerably more grey area in how much he is at fault, it not even clear who had right of way.

If the driver diligently stopped the stop sign, then pulled forward having right-of-way, and then Chrisso blew through his stop sign, then the driver is not at fault.

See?

I see that clearly.

But where are you getting all of this stop sign stuff from?

So far, I gather that the driver had a stop sign but where does chrisso's come from? You see, far too many details missing from the OP.

From the OP's description I have a T-junction. With a driver pulling out onto the main road from said junction and hitting chrisso.

A little bit later we are notified that the driver has a stop sign.

Now either way, I still have chrisso on the main road and this driver pulling out onto it and hitting him.

Of course, chrisso could be coming out of the T-junction, or both could have stop signs, or anything. But the OP must clarify the exact scenario.
 
  • #18


DaveC426913 said:
jj, there's no way to calculate this in a vacuum of facts. You have no idea how wide the lanes are, or the sidewalk, no idea how far into the grass he went, or how far down the street on his own path he went.

Vacuum facts?

Just using average lane width to get an approximate flight distance.

Bear in mind that in the OP we are told he went "flying 25 odd metres" and now we are told he was launched ~48ft through the air. That means the other ~34ft is bike travel distance? Skid distance?

Just trying to get a picture of what happened in my head.

From my previous post, there's far too much assumption here to be useful. Unless the OP clarifies things, all we know is that a car coming from a stop sign hit him and as such, the car is in the wrong whether the driver stopped or not (a) he may have ran a stop sign, b)he didn't see the bike coming and pulled out. Both the drivers fault.). That's the end of it - unless we get more info that potentially puts chrisso in the wrong.
 
  • #19


probably best if i get some exact measurements. i tried to find somewhere online that might have measurements but i think my best bet will be to go there with a tape measure.
 
  • #20


chrisso said:
probably best if i get some exact measurements. i tried to find somewhere online that might have measurements but i think my best bet will be to go there with a tape measure.

Can you explain the exact scenario?

What happened (from your view) exactly?

The way I read your OP and subsequent posts put the driver in the wrong. There's obviously something we're missing.

You neglected to mention the drivers stop sign in the OP for a start.
 
  • #21


jarednjames said:
But where are you getting all of this stop sign stuff from?
Precisely. Which is, as you point out, why, absent facts, all things are possible.


jarednjames said:
From my previous post, there's far too much assumption here to be useful. Unless the OP clarifies things, all we know is that a car coming from a stop sign hit him and as such, the car is in the wrong whether the driver stopped or not (he didn't see the bike coming). That's the end of it - unless we get more info.
Right, so I don;t know why tried to assign numbers and then claimed it didn't add up. (Of course it doesn't add up - you picked the numbers!)

We are in agreement, I just think you're overstating it.
 
  • #22


jarednjames said:
Of course, chrisso could be coming out of the T-junction, or both could have stop signs, or anything. But the OP must clarify the exact scenario.

sorry, i forget that I am explaining this to someone who has never seen the road. haha

i was traveling along the hwy at ?mile/hr the speed limit is 95 mile/hr but i don't remember how fast i was going and i MAY have been going a bit faster.

he pulled out of a side street (which has a stop sign) and hit me sending me flying over the hwy
 
  • #23


chrisso said:
sorry, i forget that I am explaining this to someone who has never seen the road. haha

No, you neglected to mention everything.

As someone who has driven 120,000 miles in 3 years I'd say I've got a fair bit of experience.
i was traveling along the hwy at ?mile/hr the speed limit is 95 mile/hr but i don't remember how fast i was going and i MAY have been going a bit faster.

he pulled out of a side street (which has a stop sign) and hit me sending me flying over the hwy

So either way, either he didn't stop for a stop sign or he did stop but didn't check for oncoming traffic (you) and as such hit it. At what point can you be blamed?
 
  • #24


DaveC426913 said:
Right, so I don;t know why tried to assign numbers and then claimed it didn't add up. (Of course it doesn't add up - you picked the numbers!)

The OP has provided the numbers and approximate distances (he gave 4 lane widths - which unless you have some epically wide roads the average is good enough for a rough estimate- and 25 odd metres of flight). All I wanted was a very rough estimate for a picture in my head.

There's a difference between assigning rough estimates to given data (average of 12ft per lane for the OP's given 4 lane width) and simply plucking random details from thin air (everyone having a stop sign).

I'm simply asking the OP for more detail - specifically the part which puts him in the wrong.
 
  • #25


jarednjames said:
As someone who has driven 120,000 miles in 3 years I'd say I've got a fair bit of experience.
At first I thought the same thing you did: he's casting aspersions on our experience, saying we've never seen a road, haha.

No, he said: the road.
sorry, i forget that I am explaining this to someone who has never seen the road. haha


He's apologizing. As in: he's realized that we could not be expected to know what the scene looks like where the accident occurred.
 
  • #26


DaveC426913 said:
At first I thought the same thing you did: he's casting aspersions on our experience, saying we've never seen a road, haha.

No, he said: the road.

He's apologizing. As in: he's realized that we could not be expected to know what the scene looks like where the accident occurred.

Ah, with you. Ha.

I retract that part then.
 
  • #27


jarednjames said:
There's a difference between assigning rough estimates to given data (average of 12ft per lane for the OP's given 4 lane width) and simply plucking random details from thin air (everyone having a stop sign).

For my part, I see a difference between
- making guesses and concluding something might happen (if there were a stop sign, that would change the scenario), and
- making guesses and concluding something would not happen (I calculate lanes this size therefore conclude it doesn't make sense).
 
  • #28


My take:
The motorcyclist was traveling along the main road in excess of the speed limit (95 mph? Really?). The other motorist stopped at the stop sign, checked for traffic within a reasonable distance from the intersection and started to pull out, not seeing the other vehicle traveling at the higher than expected speed and hit the motorcyclist.

The police officer is favouring the motorist due to that unexpected high speed and is assuming that had the motorcyclist been traveling at the speed limit, the motorist would have correctly estimated the time needed for him to safely clear the intersection and not pulled out. The officer likely believes the motorist was acting within accepted limits of awareness; therefore, he's putting the brunt of the blame on the motorcyclist because of the excessive speed.

The motorcyclist doesn't want to be held responsible for the accident and is wanting to prove that the accident would have occurred regardless of his approach speed, thereby absolving him of fault.

Anyone admitting that they "MAY have been going too fast" knows that they were - been there, done that.
 
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  • #29


DaveC426913 said:
He's apologizing. As in: he's realized that we could not be expected to know what the scene looks like where the accident occurred.

yes i was aplogising, most people I've spoken to about the event are local.

i would go out and get measurements now but the kids are asleep and the wife is out. hahaha, when she gets home i will go and measure it because now it is late at night here and very little traffic.
 
  • #30


mender said:
My take:
The police officer is favouring the motorist due to that unexpected high speed

Anyone admitting that they "MAY have been going too fast" knows that they were - been there, done that.



I concur. The OP confesses to traveling in excess of 95mph.

(I would be interested to know where there are 95mph speed limits.)

The OP survived a collision with a vehicle while traveling at 95+mph. Perhaps he should count his lucky stars they're not picking him up with a shovel and hose.



Another thought: if the OP is doing 95, and the car pulling out is doing ... significantly less ... how is it even possible that the car T-boned the bike?
 

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