Slopes and tractor tilt

[nebraskasparks]

Here's some documents that came from a discussion labeled How to Kill Yourself without Knowing

We have data that says we can flip a tractor to a point of no return in 3/4 of a second on dry level ground doing things we shouldn't be doing. We'll be on our back in another 3/4 of a second which means the total maneuver takes 1.5 seconds and can be "much quicker" provided the surface conditions are not dry, the ground is not level etc.

We've documented that it can take up to 5 seconds to react to a startling situation that we have not anticipated.

Isaac Newton and Albert Einstein's theories apply to tractors and aircraft in many of the same ways.

Documentation is as follows:

CONTRIBUTIONS TO THE STUDY OF THE DYNAMICS OF AGRICULTURAL
TRACTORS EQUIPPED WITH FRONT-END LOADER AND REAR FORKLIFT LOADER
Simion Popescu, Nastase Sutru
Transilvania University of Brasov/Romania, Faculty of Alimentation and Tourism
simipop38@yahoo.com, sutru_nastase@yahoo.com

www.harristechnical.com/articles/human.pdf

Driver Reaction Time by Dr. Marc Green

Personal experience with F-4 accident from 250 feet

Jerry Miculek - S&W Demo - Parte 1 - Bing Videos

National Ag Safety Database - Tractor Overturn Hazards

Visual Expert Human Factors: Driver Reaction Time
__________________
Safety first!
Proverbs 1:32
"For the waywardness of the naive will kill them,And the complacency of fools will destroy them.
Keep your ROPS up, your bucket low and plenty of weight to counter your FEL...
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Old 11-07-2010, 11:41 AM

 

[MoreCowbell]

A FEL is always to your detriment on a sideslope. All of its weight is forward and some of it overhangs the front axle. All stability comes from the rear. The more and further weight is shifted forward the worse it is for stability. At least remove your bucket if its QA. Most effect for least effort. :thumbsup:
larry

I know that this thread has morphed a littel since Spyderlk's post, but I want to say that he is 100% right IMO. If we are talking about something rolling over, we need to look at the axis around which it is rolling. When your CG is over the roll axis, that is when you start rolling. So its not just the height of the CG that is important, but where it is in relation to the roll axis.

Since the front axle on the tractor pivots around its center, the roll axis is a line drawn from the bottom of the downhill rear wheel and up through the front axle pivot bolt (picture a tractor starting to roll and you'll see what I mean). It proceeds forward on that same angle, which is toward the uphill side.

Hanging any weight off the front would move the CG forward. Since the roll axis moves toward the uphill side as you move towards the front of the tractor, simply moving the CG forward brings the CG more and more over the top of the roll axis and closer to the tipping point.

 

[dennis52]

I know that this thread has morphed a littel since Spyderlk's post, but I want to say that he is 100% right IMO. If we are talking about something rolling over, we need to look at the axis around which it is rolling. When your CG is over the roll axis, that is when you start rolling. So its not just the height of the CG that is important, but where it is in relation to the roll axis.

Since the front axle on the tractor pivots around its center, the roll axis is a line drawn from the bottom of the downhill rear wheel and up through the front axle pivot bolt (picture a tractor starting to roll and you'll see what I mean). It proceeds forward on that same angle, which is toward the uphill side.

Hanging any weight off the front would move the CG forward. Since the roll axis moves toward the uphill side as you move towards the front of the tractor, simply moving the CG forward brings the CG more and more over the top of the roll axis and closer to the tipping point.

And having a 600lb brushog mounted low and well rear of the tractor (with fel), should act as a counterweight and move the CG back to the rear.

 

[Boeing]

Thanks for all this input and thought. One last....well, maybe not...question. If the front end loader is just inches above the ground....wouldn't it contact the ground at the earliest roll tendancy? Thereby acting as an "outrigger" Another idea is ADDING weight to the rear impliment? (or stay off the dam hill) thanks:ashamed:

 

[RoyJackson]

Thanks for all this input and thought. One last....well, maybe not...question. If the front end loader is just inches above the ground....wouldn't it contact the ground at the earliest roll tendancy? Thereby acting as an "outrigger" Another idea is ADDING weight to the rear impliment? (or stay off the dam hill) thanks:ashamed:

Maybe it would act as an "outrigger", but I wouldn't bet my life on it...

 

[North Country]

Maybe it would act as an "outrigger", but I wouldn't bet my life on it...

I wouldn't even bet my tractor on it.

 

[TripleR]

Thanks for all this input and thought. One last....well, maybe not...question. If the front end loader is just inches above the ground....wouldn't it contact the ground at the earliest roll tendency? Thereby acting as an "outrigger" Another idea is ADDING weight to the rear implement? (or stay off the dam hill) thanks:ashamed:

I was thinking of that the other day as I was working on some slopes repairing wash outs and like the others, there are just so many variables that I prefer not to count on it. It may very well do so, but you have to pick it up to get out of there anyway. I was moving material and had to have the FEL on and used it to "steady" the tractor a couple of times, but it sure is nerve wracking.

 

[Reg]

Thanks for all this input and thought. One last....well, maybe not...question. If the front end loader is just inches above the ground....wouldn't it contact the ground at the earliest roll tendancy? Thereby acting as an "outrigger" Another idea is ADDING weight to the rear impliment? (or stay off the dam hill) thanks:ashamed:

This is the 4-point landing HOPE (prayer ?).
I really do think that it(the FEL and bucket) would be getting you out of a situation that it had (helped to) get you into.
Having landed the bucket, you still need to recover the tractor, but you now have the time for a few deep breaths and some careful planning.
The tractor IS more tippey with a FEL and bucket on, so you are faced with a better chance of recovery at an earlier stage.

I could argue it either way - - and from time to time DO argue it BOTH ways (-:

One thing that keeps running through this thread is that we deal only with known single dimension slopes, known C of G, known tipping points, etc. and that we can calculate and predict it all.
The reality is that these things CHANGE with different implements, different ground contours, different rocks, roots, gopher holes, etc. as we move.
Every FOOT of ground covered can be different, knowing that you are on an n% slope and your C of G is x inches above your axle center line is pretty much useless knowledge.

 

[SPYDERLK]

Thanks for all this input and thought. One last....well, maybe not...question. If the front end loader is just inches above the ground....wouldn't it contact the ground at the earliest roll tendancy? Thereby acting as an "outrigger" Another idea is ADDING weight to the rear impliment? (or stay off the dam hill) thanks:ashamed:

Yes, but less promptly than you might think. The bucket rises some during a tip owing to the FEL attachment point on the tractor well rearward of the front pivot. Also, there is some play in the FEL before the slop between supporting weight and applying downforce is taken up. Skimming the ground is good -- an inch is ok -- a few inches will likely scare you real bad but would still probably save you.
larry

 

[kday64]

So I have often joked with my friends that "surely can't be the dumbest person ever to try this".

It appears that amongst those there on TBN "I am." I am a believer that following the manual will save me $250 and the time associated with an insurance claim.

Straight up and straight down steep inclines always facing down.

If you want to add stability put several hundred pounds under you tractor on a rail and pulley system such that you can move the weight from 24-36" outboard on either side of the tractor. (Place the weight on the up hill side.) Assuming you are transversing along the side of the hill.

~Kevin