Fatal tractor rollover

[Mace Canute]

Safest method I've seen for pulling is attaching from the back, under the tractor to the front of the tractor. Impossible to flip it over backwards pulling that way. (at least the best method to prevent back flip)


Not to mention it continues to load down the tractor the harder you pull.

Joel

Let's consider this method compared to hooking onto the drawbar. What causes a tractor to go over backwards? The front end comes up and rotates around the rear axle before the tires lose traction. Pulling from a high point increases the mechanical advantage that tends to cause the tractor to go over backwards. If you have hooked to the drawbar, the attachment point lowers farther the higher the front end rises. If you have a chain or cable ran under the tractor, it won't lower the attachment point as the front end rises. It remains where ever it touches the tractor frame. Which situation is safer? I'd have to say attaching to the drawbar.

 

[soulasphil]

It's a great pity accidents like that still happen. The load must be attached as low as possible and preferably with a real hook designed for the job. Old automatic hook from my Massey 35 and more recent JD 3520 automatic hook.

 

[k0ua]

I have seen hundreds of tractors at 45deg up in the air or better by pulling a very heavy load from the drawbar. the only thing that kept them from going over was the guy blowing the whistle and the operator pushed in the clutch or the engine stalled: Think Tractor pull. Again Hundreds of tractors. the only reason it is not thousands is because I quit going to tractor pulls. Don't doubt for a second that pulling against an imoveable object will not put your front end up in the air from the drawbar which is well below the axle line. of course pulling from the top link will put your front end up a whole lot sooner! And now that I have loaded tires and a big counterweight on the back I bet I can pull my front end up pretty easy too! Come to think of it maybe that is why somedealers send out tractors without fluid in the tires and no ballast box. Maybe they are counting on wheel spin to save people from killing themselves with back-flips. Who knows?
James
K0UA

 

[Duffster]

I have seen hundreds of tractors at 45deg up in the air or better by pulling a very heavy load from the drawbar. the only thing that kept them from going over was the guy blowing the whistle and the operator pushed in the clutch or the engine stalled: Think Tractor pull. Again Hundreds of tractors. the only reason it is not thousands is because I quit going to tractor pulls. Don't doubt for a second that pulling against an imoveable object will not put your front end up in the air from the drawbar which is well below the axle line. of course pulling from the top link will put your front end up a whole lot sooner! And now that I have loaded tires and a big counterweight on the back I bet I can pull my front end up pretty easy too! Come to think of it maybe that is why somedealers send out tractors without fluid in the tires and no ballast box. Maybe they are counting on wheel spin to save people from killing themselves with back-flips. Who knows?
James
K0UA

The short length of the chain makes the difference in a tractor pull not to mention they pull from a fairly high point on purpose.

 

[horse7]

Theres been long discussions about "how can you flip a tractor if the load attach point is below the axle...".

It boils down to if the rear tires slip but still have some traction-- which applies torque to the axle-- then the tractor can slip backwards (if the object is immovable) while flipping over (if the object is mobile, the object moves further than the tractor, i.e., the distance between the load and tractor decreases as the tractor pulls the load under and the tractor nose goes up). People think only of the tractor going frontwards but in this case that doesn't necessarily happen, and it doesn't have to go far to go over backwards. If the tires just slip without having enough force to lift the front, you sit there, same if the engine stalls.

I like that automatic hook thingie, seems like a good idea, better than a long drawbar tongue on the tractor that slams into the ground to slow or stop a flip.

 

[1950T]

hitch height for farmstock is 21in. pro & super stock run a bit higher hitches but they allso have wheelie bars/skid bars and cages.

 

[k0ua]

hitch height for farmstock is 21in. pro & super stock run a bit higher hitches but they allso have wheelie bars/skid bars and cages.

Ok on 21 inches, but wouldn't that still be well below the axle line of the tractors involved,? and cannot they still flip over? My point was that some seemed to think it was "impossible" to raise the front end when hooked to the drawbar because it was well below the axle line. It is not. My drawbar is 13 inches, while I havent tried to do it, I bet I could raise the front end. I have also pulled some heavy loads uphill without lifting the front end, but they did move, they were not im-mobile. That was all I was trying to say about the tractor pulls, I am no expert by any means, but they are an example of raising the front end easily. Of course they dont have a loader on the front either.
James
K0UA

 

[Duffster]

Ok on 21 inches, but wouldn't that still be well below the axle line of the tractors involved,? and cannot they still flip over? My point was that some seemed to think it was "impossible" to raise the front end when hooked to the drawbar because it was well below the axle line. It is not. My drawbar is 13 inches, while I havent tried to do it, I bet I could raise the front end. I have also pulled some heavy loads uphill without lifting the front end, but they did move, they were not im-mobile. That was all I was trying to say about the tractor pulls, I am no expert by any means, but they are an example of raising the front end easily. Of course they dont have a loader on the front either.
James
K0UA

Just because you can raise the front end doesn't mean you can flip it over.

 

[1950T]

Ok on 21 inches, but wouldn't that still be well below the axle line of the tractors involved,? and cannot they still flip over? My point was that some seemed to think it was "impossible" to raise the front end when hooked to the drawbar because it was well below the axle line. It is not. My drawbar is 13 inches, while I havent tried to do it, I bet I could raise the front end. I have also pulled some heavy loads uphill without lifting the front end, but they did move, they were not im-mobile. That was all I was trying to say about the tractor pulls, I am no expert by any means, but they are an example of raising the front end easily. Of course they dont have a loader on the front either.
James
K0UA

no loader but most of the guys that are hardcore do weigh the front end for the reason that when that front end comes up all that weigh transfers to the rear. most weight bars on pro's and supers are from 24-30in front of the grill. my 9000 comes in light. i hang 1000lbs on the front and still manage to get the front end up. what does a loader weigh? i notice most here are of the compact/sub compact size id guisimate those loaders weigh between 650-750lbs.

even hooked to the drawbar pulling a 2000lb+ silage wagon ive never had a front end come up.

 

[RoyJackson]

The short length of the chain makes the difference in a tractor pull not to mention they pull from a fairly high point on purpose.

Also, when we pull, it starts at a low RPM. We're not popping the clutch as they do at tractor pulls.

k0ua, that probably wasn't a really accurate comparison...

Rigging to a tractor's drawbar results in preventing the axle from rotating around the (unmoving) tires. I'm sure, with enough torque and traction, this "opposite movement" can be overcome which would result in a rear rollover even with the load rigged to the drawbar. I doubt if it's very common...most tractors wouldn't have the torque or traction to do this. But I do suggest it's possible, espcially if the clutch was rapidly engaged (popping the clutch).

I'd read about this one years ago, but found it interesting: Farmer in the Midwest (I want to say Nebraska) parked his machine in a field overnight during the winter. Went out the next morning, started it and shifted into gear. The tires had frozen to the ground and the axle rotated about the tires....a rear rollover. Killed him, IIRC. This one had been posted or linked to a post on TBN withinthe first year of my TBN membership, so it had to been 2001.