Calculations: why tie-down strap tension and angle impacts load stability
A strap tensioned to 150 lbs. in position B results in a lateral force of 63 lbs. A strap tensioned to 150 lbs. in position c results in a lateral force of 106 lbs. This creates an imbalance of 43 lbs. (106 lbs. –63 lbs.)
In order to equalize the lateral forces you can either increase the tension in B or decrease the tension in C.
If you choose to increase the tension in B you will need to increase the resulting lateral force by 43 lbs. to 106 lbs.
You will need the increase the strap tension from 150 lbs. to 251 lbs. This would also increase the down force to 227 lbs. (251 lbs. x sin 65 deg. = 227 lbs.)
If you choose to decrease the tension in C you will need to decrease the resulting lateral force by 43 lbs. to 63 lbs.
You will need the decrease the strap tension from 150 lbs. to 89 lbs. This would also decrease the down force to 63 lbs. (89 lbs. x sin 45 deg. = 63 lbs.)