The area under the passenger cabin is pretty constrained. 737 operators pretty much just chuck luggage into the hold. And because it’s a manual operation, nob

The area under the passenger cabin is pretty constrained. 737 operators pretty much just chuck luggage into the hold. And because it’s a manual operation, nobody is going to sneak a huge chunk of tungsten or DU onto the plane, at least not in quantities that would throw off weight and balance on a 737.