DOESN'T ADD UP Published March 3, 2011 By Retired Gunnery Sgt. "Hank" Haase Via e-mail -- Entertaining and informative articles in the November/December 2010 issue of Torch. I especially liked the cover story ("A Slippery Slope," page 8), the article on the kid who had the fork go through his nose ("That's Gotta Hurt!" page 6) and the story on the plane that landed itself ("Plane Lands Itself after Pilot Ejects, page 16). I did have a question though. The caption on page 20 of the plane article says that the aircraft is number 58-0787. But in the picture the tail flash reads 0-80787. Why the difference? Great question! Air Education and Training Command's flight safety experts did a little research and found out that in the 1950s, many airplanes left over from the World War II era were still in service, exceeding their expected service lives of less than 10 years. To avoid potential confusion with later aircraft given the same tail number, these older aircraft had the number zero and a dash added in front of the tail number to indicate that they were more than 10 years old. It was hoped that this would avoid confusion caused by duplication of tail numbers between two aircraft built over 10 years apart. However, this was not always done, and it was not always possible uniquely to identify an aircraft by a knowledge of its tail number. This practice was eventually discontinued when people started referring to the number "0" as being a letter "O," standing for obsolete. The requirement for the 0 prefix was officially dropped April 24, 1972.