These photos were taken in the USA with the US Marine Corps. They show me just after take-off practising an infiltration and extraction technique called SPIE Rigging. (SPIE being Special Insertion and Extraction). Pairs of soldiers are connected to a rope under a helicopter so that they can be picked up or dropped off in dense jungle. Both hands are free to hold and (if necessary) fire weapons if there are enemy present. This is quite a thrill as the heli flies at around 400 feet.
Oh, by the way, I am one of the pair second from the bottom.