With a neck so scrawny she'll no doubt snap it like a twig. Shouldn't have skipped those neck muscle exercises.
Although, she is probably a highly trained soldier(assuming) and if we apply real life physics...she'll probably be fine. Necks are pretty hard to snap, turns out. She should be more worried about being dragged off with the parachute cause that'll be what will kill her.
Well, jumping out of a plane, no matter if you are a paratrooper or not, is always a gory way to die, if not done properly. She might be fine, but it will sure as hell give her some painful experience.