DJ, this is a British invention,perfected by ourselves at a secret airbase in the 19%%`s and is being flagrantly flaunted by you N.Americans.In order to t/o at high gross weights in underpowered piston helo`s such as the Whirlwind 3/7(H-19) , in a restricted area, a technique was developed whereby a stout pole was inserted into the ground, in the middle of the t/off area and the winch hook was put over the pole. As the a/c could not hover,it was accelerated,a la running t/o.As it got faster,the winch /op. paid out more cable and the a/c would accelerate more! Upon reaching translational lift,the a/c would become airborne,and the hook would slide off the pole-voila,airborne in a very limited area! As the a/c was /had CCW rotor rotation,you went around to the right,as it reduced the added t/rotor effect,giving slightly more power available to accelerate.
Landings at heavy weight were slightly more difficult, as the winch cable had to be paid out fully as you approached the pole,and a man had to hook over the pole as one flew around at a speed of 20-30 kts, gradually reducing the height,and then the w/man would start to wind-in the cable and allow one to do a circular running landing,dizzy,but intact!!
