Cargo holds generally have no heat or air conditioning, so they can reach extreme temperatures quickly. In one case, five dogs were loaded onto a flight that was delayed for nearly three hours in sweltering heat. Passengers heard the dogs' frantic barks, but the airline refused to do anything. Most cargo compartments are also unventilated to help prevent fires. When the oxygen is gone, so is the animal.
Tragedies also occur because of improperly trained or uncaring airline personnel.
Sometimes cats and dogs escape from carriers damaged in transit and become lost inside airplanes or airplane hangars, never to be found. Ask for the airline's rules for animal transport to avoid problems. If you are traveling abroad, or to Hawaii, check with the relevant embassy for quarantine laws. A lengthy quarantine can be a stressful ordeal for an animal. Be sure to use a sturdy, escape-proof carrying kennel, as cats can easily squeeze through small openings.