Strange thing about aircraft is that they do still tend to fly, even hanging below a helicopter. The RAF learned this many years ago when lifting a Harrier wing.....
Not only aircraft. I once had part of an army “medium girder bridge” in a net decide it wanted to take over the flight.....closest I got to jettisoning an underslung load. It was classified as a stable load, seeing that it consisted of heavy aluminium box sections, but the damned thing suddenly moved in the net, changed its mind and appeared just outside my window!