Catching a free flight sounds nice, but not when you risk your life to do so. Stowing away on an airplane involves hiding in the wheel well of the craft. It has not only has serious implications for air safety, but also typically results in death. Of the 113 people who stowed away in the United States between 1947 and June 2015, 76% died. Flying unprotected leads to death from hypothermia or oxygen depravation. Many died when they were crushed by the landing mechanism that retracts into the wheel well or when they fell from the plane after takeoff.
Many people die mid-flight, but at least their deaths are accounted for. According to the Federal Aviation Association, the number of stowaways is likely higher than records show because so many bodies fall into the ocean.