Jack knifing & weather conditions

[gary]

Was watching the news at noon, it showed two tractor trailers that jack knifed last night in the snow. What is the main cause of that- is that the driver travelling to fast for the weather conditions, slamming brakes/accelerating to quickly, not to know how to controll a skid when it occurrs or is it just the weather/road conditions and sometimes you just can't prevent it?
There alot of drivers with a lot of experience on the forum, so I guess I'm wondering, how do you avoid these condition (instead of staying out of the truck) and how to you deal with it when they do occurr?:broke:
I've asked my instructors, read everything I could find (THSAO'S TIPS FOR WINTER DRIVING), I guess I'm asking about your personal experiences.:23_30_126[1]:

[Pipeman]

Problem can be any of the above.. Usually the drivers' fault.

Main reason -------------"Too fast for road conditions" .

[maan]

Problem can be any of the above.. Usually the drivers' fault.

Main reason -------------"Too fast for road conditions" .Including when you are driving for the road conditions, but then someone else spins out if front of you..

Trailer brakes that may be fine for dry conditions, but may be on the tight side, or worse lock up easily, can ruin your day in slick, wet (or icy) snow conditions.

I was in dry conditions once at ~ 100 clicks, when turned out, a very aged man quite suddenly changed lanes pretty much right in front of me. I was able (& only option was) to slam on the brakes.. big time & avoid contact.

When I checked my mirrors, there was a HUGE rubber smoke cloud.. behind me & I felt nothing at the wheel.

Yes, you can be doing everything right, but sometimes, it just can't be prevented.

[Drifter]

If you are doing everything RIGHT!!! 99.9% of the time the driver misjudged road conditions, following distance, over reacted or under reacted,

[Pipeman]

I've run thousands of miles on roads like these and never had any incidents:


http://img.photobucket.com/albums/v16/Pipeman/YieldSign005.jpg
http://img.photobucket.com/albums/v16/Pipeman/YieldSign003.jpg
http://img.photobucket.com/albums/v16/Pipeman/YieldSign001.jpg
http://img.photobucket.com/albums/v16/Pipeman/2006-01-12120.jpg
http://img.photobucket.com/albums/v16/Pipeman/2006-01-12112.jpg

[maan]

How to Avoid Jackknifing (http://auto.howstuffworks.com/auto-parts/towing/vehicle-towing/maneuvers/how-to-avoid-jackknifing.htm)
http://auto.howstuffworks.com/auto-parts/towing/vehicle-towing/maneuvers/how-to-avoid-jackknifing.htm

http://www.thsao.on.ca/docs/winter_tips.pdf
Combination Vehicle Jack Knife
There are two types of jack knifes:
a/ A tractor jack knife in which the rear of the tractor skids sideways.
b/ A trailer jack knife in which the rear of the trailer slides and comes around.
Repeat tests have shown that if a jack knife develops beyond 15 degrees it is almost impossible to recover. The faster this 15-degree angle develops the greater the severity and potential damage from the jack knife. Since a jack knife can go to 15 degrees in as little as 1½ seconds, any attempt to recover must be fast in order to take preventative action.
How to Prevent a Jack Knife
First, recognize the road and weather conditions and constantly monitor these conditions. Be prepared for the unexpected. Identifying a white out or a patch of fog and adjusting your speed before you get into it is just common sense. You’ll never go wrong by slowing down.http://www.redwoodsgroup.com/YMCA/BB15MiscIncidentsRMT.pdf (http://www.thsao.on.ca/docs/winter_tips.pdf)
Roll over, jack-knife, and other off-road incidents are normally preventable as they are generally caused by
exceeding the vehicle's safe performance limits or other driver error.
Jack-knifing arises from a drive-wheel skid caused by over-braking at excessive speed, often during inclement weather. In a
drive-wheel skid, the sliding rear of the trailer will take the path of least resistance, swinging wide in an attempt to
pass the van rather than push against it. When the angle between the van and the trailer exceeds 15 deg, a jack-knife
will almost always occur (see Back to Basics 10: Inclement Weather).
Driving appropriately for the road, weather, and traffic conditions and within the safe operating capabilities of both
vehicle and driver will prevent most of these types of incidents. Application of defensive driving techniques such
as scanning properly, maintaining an adequate following distance, and adequately controlling blind spots will
provide sufficient space for life in all but the most unusual circumstances.http://www.e-z.net/~ts/ts/jack.htm (http://www.e-z.net/%7Ets/ts/jack.htm)
Bottom line: In an emergency situation-without ABS- you've got your choice of directional stability or maximum braking. If you dynamite the brakes you may lock some axles and get one of the problems listed above. Which axles, if any, lock depend on the condition of the brakes and the weight on each axle. Case 2. should be avoided at virtually all costs, if you jackknife you may rollover. Case 3 is a little better, it will take a little longer for trailer swing to get you into serious trouble, unless the trailer hits another vehicle when it swings out. Case 1. is the least dangerous, you can't steer much in a semi anyway. A hard steering maneuver will roll you.http://comps.fotosearch.com/comp/BDX/BDX383/freeway-traffic-winter_%7Ebxp70470.jpghttp://comps.fotosearch.com/comp/BDX/BDX383/freeway-traffic-winter_%7Ebxp70470.jpg

[maan]

Bottom line is you could be doing everything right, & someone else takes you out.

In one incident, 2 tractors (with trailers) were running side by side & they touched. Maybe one was passing, dunno what the details were.

Incidents can occur where once started, there is no recovery & you're in it for the ride; whether you are to blame, or someone else.

Over the years, i've seen my share of cars spin out (outa the blue..) right around me.

BTW, someone spins out (or something happens) in front of you (& doesn't have to start right in front of you either) & you hit them, Ins considers you at fault. In some accident scenarios, cops may not charge you but Ins Co may still consider you at fault.

In the GTA, when there is snow, cars will go spinning, often without any warning & can happen right around you.

Years ago, air brake instructor at Humber used to say ~ "one of the most dangerous situations to be in, in slick conditions, is with a tractor behind you, bob tailing". http://www.fotosearch.com/bigcomp.asp?path=BDX/BDX383/bxp70470.jpg
http://img155.imageshack.us/img155/681/traffickg5.th.jpg
http://www.fotosearch.com/bigcomp.asp?path=BDX/BDX383/bxp70470.jpg

[maan]

The bottom line is ------ IF YOU JACK KNIFE DUE TO WEATHER CONDITIONS THAN IT IS YOUR FAULT BECAUSE YOU WERE GOING TO FAST FOR THE EXISTING CONDITIONS.

I am sick and tired of people refusing to take responsibility for their actions ----- unless someone is using you as a target there is no reason that you could not have avoided an accident by controlling your unit and putting yourself in a position where there is no danger.

http://auto.howstuffworks.com/auto-parts/towing/vehicle-towing/maneuvers/how-to-avoid-jackknifing2.htm

Who's to Blame?
Judging from traffic reports of jackknifing, some people may think that truck driver negligence is the source of most of the problems on the road. Spectators often don't realize that jackknifing was a result -- not a cause -- of a nasty accident. In this way, the danger of jackknifing (per se) is sometimes exaggerated in the media. Regardless, it's always best to keep a safe distance from trucks on the road.

[maan]

http://news.therecord.com/specialsections/section/impact/410468

"I checked everything, pulled out to pass, and there in front of me -- and of course, my perception of it was, it was like the size of a house -- was this huge, stretched-out truck tire right across the lane."
In that second, Wybrow could see only danger beyond the hood of her car.
"I just had this feeling -- and this is all in literally a quarter of a second -- that it would come up and come through the car and kill us."
She took the only option she saw. She swerved.

That morning, truck driver Brent Desormo was in the home stretch of his twice-weekly run hauling auto parts from Indianapolis back to Guelph. It was his daughter's 11th birthday, extra incentive for Desormo, then 38, to get to Guelph, drop off his rig and head home to Keswick in his pickup.
In his 20 years driving a transport, he had seen his share of carnage, but had never been in a serious crash.
After nearly 800 kilometres of his 830-kilometre journey, Desormo was approaching the Ayr area at about 90 km/h. He pulled into the left lane to pass a car, glancing at his right-side mirror to measure his progress.
"I looked back, I looked to the right, looked in the mirror," he recalled. "And when I looked forward, out of the corner of my eye in the vent window, I saw a car coming at me."

The green station wagon was barrelling across the barren median directly into his path. With a loaded, 15,000-pound trailer behind him, he couldn't slow down in time. He couldn't stop.
"I knew if it hit head on, I would just go over her."
Desormo did the only thing he could do. He sped up.

<snip>

The car had struck the side fuel tank on the transport, directly below Desormo. The truck jackknifed, and the cab swung into the median ditch. Diesel fuel pooled on the ground.

http://www.youtube.com/watch?v=L950YH2K_JY

[Jules]

The main cause of jack knifing is drivers that don't chain up when they sould when going down hills.

Of course, 99.9% of highway drivers don't get paid to chain up, so some are hesitant to install chains unless they are forced to. Of course, chaining up isn't really that fun either... Crawling around in the snow in the dark fitting them isn't exactly fun either.

[Pipeman]

The main cause of jack knifing is drivers that don't chain up when they sould when going down hills.

Of course, 99.9% of highway drivers don't get paid to chain up, so some are hesitant to install chains unless they are forced to. Of course, chaining up isn't really that fun either... Crawling around in the snow in the dark fitting them isn't exactly fun either.
Chains are a hell of a lot more useful to climb a hill than go down the sucker.