An average of 1.2 aircraft go missing each year, according to an illustrated map released last week by Bloomberg News that pinpoints the last known position of 83 aircraft that have gone missing since 1948. The Douglas DC-3 is the aircraft lost more often than any other in the past 65 years. The fact that the number of aircraft lost in the past 20 years has declined dramatically reflects the continual improvements in aviation safety over the past seven decades.