Sling Load Angle is the angle the legs of the sling form against the direction of the applied force.
Many people assume that as soon as an ES or Bridle is introduced then the applied force is halved and transmitted equally to the attachment points IE 1000 KG from the Snatch Strap will be seen as 500 Kg at the left attachment point and 500 Kg at the right attachment point of the ES.
If the angle formed between the front of the vehicle and the legs of the strap is 60 degrees or more (as in the piccy above) this is true and a 1,000 Kg force will appear as 500 Kg's at each attachment point.
If the ES was shorter and the angle formed decreases to 45 degrees the the 1,000 Kg force will be seen as approx 700 Kg's at each attachment point... as the angle decreases the load increases and past 60 degrees is as much as 90 % or 900 Kg's
Now, this is all pretty heavy sh1t that is the life blood of riggers etc and hats off to 'em but I prefer a simpler life so I look at it this way...
Pretty much only two things can go wrong, either a) the sling angle goes pear shaped OR b) one leg lets go and everything else stays attached. In either case the Max Load on an attachment point is now the recovery force (1,000 Kg in our example) so I rig it that way and pretend the bridle is of no assistance in sharing the load whatever
Remember the original definition and purpose of the Recovery Bridle
"allows for relative movement on the winch wire, tow rope or snatch strap to deflect from side to side allowing the towing vehicle and the vehicle being towed independence of movement"
The fact that it also has the side effect of reducing the load at the attachment points should not necessarily be relied upon
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