They say that long flights are a killer. Well, for one frequent flyer, it was just that.A woman was found dead in her seat just hours into a 16-hour trip home to Australia after a Las Vegas vacation.Cabin crew on the Qantas flight from California to Melbourne had to quickly move several other passengers afterAleisha Tracy, 33, died about three hours after takeoff Sunday. Luckily for the airline, there were two doctors on board that were able to assist the flight crew in moving the body and determining what had happened. Friends and family say she had no medical problems and was never sick. Victoria Police in Australia are awaiting the results of an autopsy to determine Tracy’s cause of death.