My ex chief pilot many years ago was transporting a body in a BN2 from somewhere in the Kabwum valley for Nadzab, they didn't have a coffin and the deceased had died just hours previously. It was agreed that the body be wrapped in plastic and then strapped into one of the seats. The family then occupied the other seats. Somewhere around the 20 mile gap the body groaned and one of the legs lifted creating havoc amongst the family members who promptly did everything they could to distance themselves from the body, this created quite a change in CofG that he was able to compensate for fortunately. I would have loved to have been a fly on the wall for that one. Apparently their screams were clearly audible above the aircrafts engines