Light, high profile vehicles in Wyoming - what's threshold?

This is a difficult read, somewhat more of a scientific analysis but with good information about blowover risks in Wyoming.


https://www.google.com/url?sa=t&sou...FjACegQICBAI&usg=AOvVaw3Sae68Ps9nxI7kw51tUGkX

 

I think they dont list a weight because they dont want the liability if they say x and x weight is good to run and someome goes out there with that weight and blows over "well u said it was safe to run , its not my fault" enter ambulance chasing lawyer here

 

Had a container on chassis empty after I delivered to Ocean City a hotels worth of Thailand made tables and chairs for 35th street group being built on bay side there. Those tables and chairs are probably still there. Which would please me.

I hit the bay bridge westbound hoping to get across before the summer squall storm got to me coming from the west. The bridge did not restrict anything when I got on from east end.

When I got to the top on the westbound span where the steel grate pavement is, the storm reached me. Put my rig and trailer against that little 29 inch or so railing and then pushed us all over about 45 degrees almost enough to just dump all of it into the bay. I ride that fuel tank outside the cab and considering jump or die or ride and die? dead is good as dead, chopped by steel grate or smash the water below.

Fortunately the wind gust quit and she came back down.

Leaving out other things, that was almost my last day in anything. Never mind trucking.

To whit I think chassis was 6000 pounds, mack short R model was maybe 14000 and the box another 3000 or so maybe if that. VERY light.

Add that to my inexperience in weather things. That got schooled FAST. Dont go up there when the sun goes away like that dummy (Myself) I had so much to learn in those days. Im just glad she came back down before I finished making a choice that was really no choice.

My first trip on the CBBT, a Policeman pulled me over. Saw how youthful I was. He took a smoke with me and started talking about CBBT to me. With me to be quiet and listen.

Thats one of the reasons why I follow the CBBT rules in storm conditions so much. They did something that was quite a gift that day over a smoke.

 

I grew up by the Sisters and thus have always had too much interested in this subject.

RV's and sprinter vans are also under "light high profile vehicles" in Wyoming. They can't really just set it to a scale weight to cover who is at risk.

FYI, they are doing studies on this trying to both improve forecasting and reduce closures. If you enjoy math you can see what they are working on now here.

http://www.dot.state.wy.us/files/li...shared/Planning/Research/RS06219_Blowover.pdf

Once they have a valid method of classifying the risk they will try to make it more specific but right now the current roles only impact a handful of trucks per hour compared to a more strict closure. Not that they don't issue these until winds hit 60 MPH which is a point where there is 2:3 that there will be a blowover accident.

What they do have today does not take the impacts of gusts working like a child on a swing but only deals with constant wind speeds.
These charts show when it is most likely that there will be a crash for semi-trucks. (5% deflection for sliding)



These numbers are not exact and they are not gospel but just hints based on what is known today. If you look at the chart <35,000 pounds according to a study by Nevada is a risk at 60 MPH which is when Wyoming issues the warning.

If you are the type of driver that is willing to slow down as much as needed and who remembers to keep some RPM available when going down a grade to recover from a trailer slide you will fair better. If you ignore cyclic increases in trailer deflection, or drive as fast as you can to satisfy your get-there-itus you will be at a much higher risk.

Here is how grim the stats are. (0.60 == 60%)



Note that overturning are far more likely to shut the road, which is why they wait until 60 MPH today to provide a warning. But even at 30 MPH winds slick roads gives a 50:50 chance that someone will overturn somewhere in the state. Remember that 30 mph to 60 mph is eight times as much force.

We are our own worst enemies here, only slowing down and/or stopping will really make this safer and help reduce the number of closures to clear.