Do the math on this?

A local newspaper article (no link online, unfortunately) states a 21 year
old man was driving a pickup truck at unspecified unsafe speed. He lost
control in a corner. The pickup slid sideways for ******* 500 ******* feet.
After that, it left the roadway and hit a tree (what size, who knows), and
that the tree was sheared off by the impact. Idiot was killed, obviously.

But I'm wondering how fast was this idiot going before he lost control?
Road conditions in the area were DRY at the time. Unfortunately, there is
no information on type of pickup or what type of tires, condition, etc.
Let's say Ford F150 with OEM tires in decent shape, how fast would that have
to go to slide sideways for 500 feet and still have enough kinetic energy to
fly through the air a bit and shear off a small tree on impact?????

Then again, would an F150 even be able to go that fast in the first place?
(I doubt it) -Dave

Mike T. wrote:
> A local newspaper article (no link online, unfortunately) states a 21 year
> old man was driving a pickup truck at unspecified unsafe speed. He lost
> control in a corner. The pickup slid sideways for ******* 500 ******* feet.
> After that, it left the roadway and hit a tree (what size, who knows), and
> that the tree was sheared off by the impact. Idiot was killed, obviously.
>
> But I'm wondering how fast was this idiot going before he lost control?
> Road conditions in the area were DRY at the time. Unfortunately, there is
> no information on type of pickup or what type of tires, condition, etc.
> Let's say Ford F150 with OEM tires in decent shape, how fast would that have
> to go to slide sideways for 500 feet and still have enough kinetic energy to
> fly through the air a bit and shear off a small tree on impact?????
>
> Then again, would an F150 even be able to go that fast in the first place?
> (I doubt it) -Dave

Without knowing if the truck rolled over (it HAD to have, wouldn't it?)
it would be hard to calculate.

Then again, if I could calculate it in the first place, I'd probably be
an accident investigator!

>> A local newspaper article (no link online, unfortunately) states a 21
>> year
>> old man was driving a pickup truck at unspecified unsafe speed. He lost
>> control in a corner. The pickup slid sideways for ******* 500 *******
>> feet.
>> After that, it left the roadway and hit a tree (what size, who knows),
>> and
>> that the tree was sheared off by the impact. Idiot was killed,
>> obviously.
>>
>> But I'm wondering how fast was this idiot going before he lost control?
>> Road conditions in the area were DRY at the time. Unfortunately, there
>> is
>> no information on type of pickup or what type of tires, condition, etc.
>> Let's say Ford F150 with OEM tires in decent shape, how fast would that
>> have
>> to go to slide sideways for 500 feet and still have enough kinetic energy
>> to
>> fly through the air a bit and shear off a small tree on impact?????
>>
>> Then again, would an F150 even be able to go that fast in the first
>> place?
>> (I doubt it) -Dave
>
> Without knowing if the truck rolled over (it HAD to have, wouldn't it?)
> it would be hard to calculate.
>
> Then again, if I could calculate it in the first place, I'd probably be
> an accident investigator!
>

Well, let's change this around a bit. Let's say Ford F150 with bald tires
on dry road, all four wheels lock. How fast do you have to be going to
slide 500 feet before you stop? That should be a pretty good estimate of
how fast the truck was travelling before it went sideways. I'm guessing
sideways it wouldn't have quite as much traction. Therefore, if it was
sliding sideways at the same starting speed, it might have enough energy
left to leave the road and shear off a tree.

Don't know if it would roll over though. It wasn't an SUV, it said pickup.
Those are top heavy, but not quite as much so. -Dave

Mike T. wrote:
> A local newspaper article (no link online, unfortunately) states a 21 year
> old man was driving a pickup truck at unspecified unsafe speed. He lost
> control in a corner. The pickup slid sideways for ******* 500 ******* feet.
> After that, it left the roadway and hit a tree (what size, who knows), and
> that the tree was sheared off by the impact. Idiot was killed, obviously.
>
> But I'm wondering how fast was this idiot going before he lost control?
> Road conditions in the area were DRY at the time. Unfortunately, there is
> no information on type of pickup or what type of tires, condition, etc.
> Let's say Ford F150 with OEM tires in decent shape, how fast would that have
> to go to slide sideways for 500 feet and still have enough kinetic energy to
> fly through the air a bit and shear off a small tree on impact?????
>
> Then again, would an F150 even be able to go that fast in the first place?
> (I doubt it) -Dave
-----
WOW!!! Sounds remarkable, don't it?

According to a chart from Edmunds at Autotrader.com... about 90 mph
ought to cover it. Some people ought to think about that before citing
85 mph as a "perfectly safe" velocity.

http://tinyurl.com/czzqd
-----

- gpsman

"gpsman" > wrote in message
oups.com...
> Mike T. wrote:
>> A local newspaper article (no link online, unfortunately) states a 21
>> year
>> old man was driving a pickup truck at unspecified unsafe speed. He lost
>> control in a corner. The pickup slid sideways for ******* 500 *******
>> feet.
>> After that, it left the roadway and hit a tree (what size, who knows),
>> and
>> that the tree was sheared off by the impact. Idiot was killed,
>> obviously.
>>
>> But I'm wondering how fast was this idiot going before he lost control?
>> Road conditions in the area were DRY at the time. Unfortunately, there
>> is
>> no information on type of pickup or what type of tires, condition, etc.
>> Let's say Ford F150 with OEM tires in decent shape, how fast would that
>> have
>> to go to slide sideways for 500 feet and still have enough kinetic energy
>> to
>> fly through the air a bit and shear off a small tree on impact?????
>>
>> Then again, would an F150 even be able to go that fast in the first
>> place?
>> (I doubt it) -Dave
> -----
> WOW!!! Sounds remarkable, don't it?
>
> According to a chart from Edmunds at Autotrader.com... about 90 mph
> ought to cover it. Some people ought to think about that before citing
> 85 mph as a "perfectly safe" velocity.
>
> http://tinyurl.com/czzqd
> -----

Interesting information, but it's not applicable to the situation I posted
about. The article stated that the pickup slid more than 500 feet. So the
~2 seconds reaction time had already elapsed, if the driver "reacted" at all
before the slide started. Assuming that a vehicle sliding sideways would
stop exactly as fast as a vehicle stopping in a straight line, that would
mean that the vehicle in question was going considerably faster than 90MPH,
to increase his total stopping time by about 2 seconds beyond the time it
MIGHT have taken the driver to stop from 90MPH.

PLUS, the vehicle wasn't anywhere near a complete stop after 500 feet. It
still had enough energy to leave the road and shear off a tree of unknown
size.

My best guess after careful consideration is that the pickup MUST have been
travelling well in excess of 140MPH before it started sliding sideways. WTF
kind of pickup was that . . . a Tundra V8 2WD, possibly??? -Dave

In article ws.net>,
"Mike T." > wrote:

> "gpsman" > wrote in message
> oups.com...
> > Mike T. wrote:
> >> A local newspaper article (no link online, unfortunately) states a 21
> >> year
> >> old man was driving a pickup truck at unspecified unsafe speed. He lost
> >> control in a corner. The pickup slid sideways for ******* 500 *******
> >> feet.
> >> After that, it left the roadway and hit a tree (what size, who knows),
> >> and
> >> that the tree was sheared off by the impact. Idiot was killed,
> >> obviously.
> >>
> >> But I'm wondering how fast was this idiot going before he lost control?
> >> Road conditions in the area were DRY at the time. Unfortunately, there
> >> is
> >> no information on type of pickup or what type of tires, condition, etc.
> >> Let's say Ford F150 with OEM tires in decent shape, how fast would that
> >> have
> >> to go to slide sideways for 500 feet and still have enough kinetic energy
> >> to
> >> fly through the air a bit and shear off a small tree on impact?????
> >>
> >> Then again, would an F150 even be able to go that fast in the first
> >> place?
> >> (I doubt it) -Dave
> > -----
> > WOW!!! Sounds remarkable, don't it?
> >
> > According to a chart from Edmunds at Autotrader.com... about 90 mph
> > ought to cover it. Some people ought to think about that before citing
> > 85 mph as a "perfectly safe" velocity.
> >
> > http://tinyurl.com/czzqd
> > -----
>
> Interesting information, but it's not applicable to the situation I posted
> about. The article stated that the pickup slid more than 500 feet. So the
> ~2 seconds reaction time had already elapsed, if the driver "reacted" at all
> before the slide started. Assuming that a vehicle sliding sideways would
> stop exactly as fast as a vehicle stopping in a straight line, that would
> mean that the vehicle in question was going considerably faster than 90MPH,
> to increase his total stopping time by about 2 seconds beyond the time it
> MIGHT have taken the driver to stop from 90MPH.
>
> PLUS, the vehicle wasn't anywhere near a complete stop after 500 feet. It
> still had enough energy to leave the road and shear off a tree of unknown
> size.
>
> My best guess after careful consideration is that the pickup MUST have been
> travelling well in excess of 140MPH before it started sliding sideways. WTF
> kind of pickup was that . . . a Tundra V8 2WD, possibly??? -Dave

I can ballpark it for you.

If we assume 1 g deceleration -- a very generous estimate:

a = 32 ft/s^2

d = 500

v = ?


Using the forumla v(final)^2 = v(initial)^2 + 2ad, and remembering the
final velocity in this case is 0.

0 = v^2 + 2 *(32) * 500

v = (32000)^(1/2) = 179 mph.

So if deceleration equalled 1 g, the truck would have had to be going
179 mph to slide for 500 feet. Even at 0.75 g, the truck would still
have had to be going 155 mph.

--
Alan Baker
Vancouver, British Columbia
"If you raise the ceiling 4 feet, move the fireplace from that wall
to that wall, you'll still only get the full stereophonic effect
if you sit in the bottom of that cupboard."

>> My best guess after careful consideration is that the pickup MUST have
>> been
>> travelling well in excess of 140MPH before it started sliding sideways.
>> WTF
>> kind of pickup was that . . . a Tundra V8 2WD, possibly??? -Dave
>
> I can ballpark it for you.
>
> If we assume 1 g deceleration -- a very generous estimate:
>
> a = 32 ft/s^2
>
> d = 500
>
> v = ?
>
>
> Using the forumla v(final)^2 = v(initial)^2 + 2ad, and remembering the
> final velocity in this case is 0.
>
> 0 = v^2 + 2 *(32) * 500
>
> v = (32000)^(1/2) = 179 mph.
>
> So if deceleration equalled 1 g, the truck would have had to be going
> 179 mph to slide for 500 feet. Even at 0.75 g, the truck would still
> have had to be going 155 mph.
>
> --
> Alan Baker
> Vancouver, British Columbia

Wow. I guess for a change this really was unsafe speed. 155MPH estimated,
and that doesn't take into account that it still left the road and sheared
off a tree!!! Holy sh^%, maybe closer to 200MPH. What kind of pickup was
this?

What is the fastest production pickup truck sold today in the U.S.? Any
capable of speeds well in excess of 150MPH? -Dave

In article .com>,
says...

>WOW!!! Sounds remarkable, don't it?
>
>According to a chart from Edmunds at Autotrader.com... about 90 mph
>ought to cover it. Some people ought to think about that before citing
>85 mph as a "perfectly safe" velocity.

What does one have to do with the other? You have the case of an idiot driving
to fast for conditions and losing control of their vehicle. There are many
roads where the conditions will allow you to safely drive 85mph, and faster.
The important part is being able to recognize when the conditions allow the
higher speeds.
------------------
Alex

In article ws.net>,
says...

>Assuming that a vehicle sliding sideways would
>stop exactly as fast as a vehicle stopping in a straight line, that would
>mean that the vehicle in question was going considerably faster than 90MPH,
>to increase his total stopping time by about 2 seconds beyond the time it
>MIGHT have taken the driver to stop from 90MPH.

Assuming the driver knows how to properly use their brakes, a non-slidding
stop will be much shorter than a slidding stop.

>PLUS, the vehicle wasn't anywhere near a complete stop after 500 feet. It
>still had enough energy to leave the road and shear off a tree of unknown
>size.

It had to be moving pretty quickly at 500 ft. Even small trees take a lot
of energy to topple.

>My best guess after careful consideration is that the pickup MUST have been
>travelling well in excess of 140MPH before it started sliding sideways. WTF
>kind of pickup was that . . . a Tundra V8 2WD, possibly??? -Dave

140 in a full size pickup would require a substantial amount of horsepower.
Maybe a Dodge SRT pickup with the Viper V10 motor will get up to that speed,
but not a plain F150.
--------------
Alex

In article >,
Alex Rodriguez > wrote:
>
>140 in a full size pickup would require a substantial amount of horsepower.

Most pickups are governed to 99-110 miles per hour. If the truck
was fishtailing for part of the distance it could leave skid marks
without slowing down much.

--
John Carr )