No, not all people are buoyant. Some people sink. I used to be able to float even with my lungs empty, but after losing 30kg I can now walk on the bottom of the

No, not all people are buoyant. Some people sink. I used to be able to float even with my lungs empty, but after losing 30kg I can now walk on the bottom of the pool will my lungs full of air. Also, even if you are buoyant, it does not follow that being strapped to some device means you can't drown.