Stuck in the pond

   / Stuck in the pond #101  
Lol. Yeah, I've got the shorts comment before. It's the cab's fault.... It makes you forget that you're working a tractor like my youth. Gotta love air conditioning when it's 105° outside, and the heat when it's in the 20s. I do forget some days that I'm actually doing work. 🙂
Heated cab or not, you're a braver man than I am if you wear shorts when it's 20 out!! :cool:
 
   / Stuck in the pond #102  
Did some research a while back on forces exerted on Anchors and required force needed to extract a mired vehicle. I want to say pulling a vehicle on level smooth ground requires about 10% of the GVW (so an 8K lb vehicle would require 800 lbs of pull to move it.). If mired, it requires more:
Mire resistance:
  • Wheel depth = 1x load
  • Fender depth 2x load
  • Cab depth 3X load
  • Pulling opposite direction of travel can reduce the load by 10% (traveling in ruts)
  • Moving wheels during extraction breaks suction and can reduce load but not in a dependable manner (40% for tracked vehicles)
  • Example: 10 Ton tracked load mired to fenders, = 20T adjusted load. By moving wheels and pulling in opposite direction, this is reduced to 10 Tons

I also found the attached Army field manual for vehicle recovery. I found this very very helpful and easy to understand.

Be aware if you are using snatch blocks - you can end up putting double the load on an anchor in some situations. Combine a snatch block with a deeply mired load and you can accidently destroy your anchor which if it is your bumper could be costly and dangerous!

View attachment 828430
Using the diagram above I ran some numbers (I think I am correct but there are folks smarter than I am on this forum who I am sure will weigh in if I am not)
Variables:
Load 4 Tons (8,000 lbs)
Tackle resistance (10% of load per snatch block sheave)
Max Winch pull (6 tons, 12,000 lbs)
Pull per line = total load with resistance / # of lines
Load per anchor = load per line * # of lines to anchor


Situation 1: Single Line:
Mechanical Advantage = 1:1
Load on Winch: 8,000 lbs
Load on Anchor: 8,000 lbs


Situation 2: Double Line:
Mechanical Advantage = 2:1
# of snatch blocks: 1
Total load: 8,000 +800 {10% tackle resistance} = 8,800 lbs
Load per line: 4,400 lbs
Load on the Anchor: 8,800 lbs
Load on the winch: 4,400
Load on the truck anchor shackle: 4,400
Total load on the truck itself across all anchor points: 8,800



Situation 3 Triple Line:
# of snatch blocks: 2
Total load 8,000+1,600 {20% tackle resistance} = 9600
Load per line: 9,600/3=3,200


Load on Winch: 3,200 lbs
Load on Anchor 1: 6,400 lbs
Load on Anchor 2: 3,200 lbs
Load on Anchor 3: 6,400 lbs
Total load on vehicle (3,200+6,400)=9,600



Consequently, if you move anchors 1 and 2 to the same tree, the tree will see 9,600 lbs of pull (3,200 of the pull being felt by Anchor 2 and 6,400 being felt by anchor 1)


____________________________________________

I was actually quite surprised to find that the layers of rope (wire or synthetic) on the winch when pulling reduces the power of the winch.

Example with a 12K lb winch
Layer 1: 12,000 (100%)
Layer 2: 9,517 (79%)
Layer 3: 7,885 (66%)
Layer 4: 6,732 (56%)
All good information BUT.... Is just single vehicle information using solid anchor point to pull against (self rescue) ... IF stuck tractor and pulling with 4WD or "other" rescue vehicle, both vehicles lack a solid anchor to pull from (assisted rescue) ..... Which vehicle moves first is how much weight or tire friction the "pulling" vehicle has, to wit, 4,500 pound Jeep pulling out a 2,600 pound SCUT stuck up to chassis in muddy creek bottom.... Guess which vehicle was first to move..... Yep it was the JEEP!....

Then there is scenario of how many tractors have "recovery " winches and convent tree nearby...
 
   / Stuck in the pond #103  
Not my quote, but when my tractor got stuck I was told, "No one with a front end loader should ever get stuck...". So, I went out and got it unstuck manipulating the loader. It was 2 days later and 2 days dryer, thought.
/oo
 
   / Stuck in the pond #104  
I was told, "No one with a front end loader should ever get stuck...".
Anybody who says this has never been stuck. 😉

As the OP found, sometimes there isn't anything for the loader to push against. If the rears are so buried that the implement is hung up, the loader is useless.I've gotten into snow, and dug a hole with the tires so that I was high centered. An old fashioned snow shovel works fir that... and a strong back. I have run a chain from the bucket hook to a tree and pulled it out that way, but won't do it again. (maybe) If the chain fails it is aimed right at your face.
 
   / Stuck in the pond #105  
All good information BUT.... Is just single vehicle information using solid anchor point to pull against (self rescue) ... IF stuck tractor and pulling with 4WD or "other" rescue vehicle, both vehicles lack a solid anchor to pull from (assisted rescue) ..... Which vehicle moves first is how much weight or tire friction the "pulling" vehicle has, to wit, 4,500 pound Jeep pulling out a 2,600 pound SCUT stuck up to chassis in muddy creek bottom.... Guess which vehicle was first to move..... Yep it was the JEEP!....

Then there is scenario of how many tractors have "recovery " winches and convent tree nearby...
I've always wondered what a 100lb delta boat anchor would do for a winch point. Even if it was used on the hitch of the recovery vehicle just aft of the vehicle then the winch did the work.
 
   / Stuck in the pond #106  
All good information BUT.... Is just single vehicle information using solid anchor point to pull against (self rescue) ... IF stuck tractor and pulling with 4WD or "other" rescue vehicle, both vehicles lack a solid anchor to pull from (assisted rescue) ..... Which vehicle moves first is how much weight or tire friction the "pulling" vehicle has, to wit, 4,500 pound Jeep pulling out a 2,600 pound SCUT stuck up to chassis in muddy creek bottom.... Guess which vehicle was first to move..... Yep it was the JEEP!....

Then there is scenario of how many tractors have "recovery " winches and convent tree nearby...

You can pull out a somewhat heavier stuck vehicle with a lighter Jeep /winch combo even with Jeep in the same mud. Just grab a couple firewood rounds and stuff them at 45* angle against the tires.

They make amazing blocks or wedges to add resistance to the Jeep. I have done this before and it worked. The blocks dug in and stopped the Jeep from sliding and the winch did the rest.
 
   / Stuck in the pond #107  
:ROFLMAO: :ROFLMAO: :ROFLMAO: Just a wild guess that you don't farm. Back in the day we would turn them around on purpose. No difference.
I ran them backwards on my JCB back in the day Helped with high speed road noise.
 
   / Stuck in the pond #108  
Ours would get turned around to get different wheel spacing. You did what you had to do back then. Row crop to 8' for 2 row tobacco cultivating.
 
   / Stuck in the pond #109  
Ours would get turned around to get different wheel spacing. You did what you had to do back then. Row crop to 8' for 2 row tobacco cultivating.
We always swapped sides when doing so to keep the forward rotation the same direction.
 
   / Stuck in the pond #110  
Granddaddy never went to the trouble. I personally think tread direction and traction is a myth just like ag tires mash grass down worse than turf and industrial tires do.
 
 
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