Nose art on aircraft has been around since about 1913. WW1 fighter pilots painted their a/c with art, sometimes painting designs on the entire aircraft. During WW2 nose art really bloomed. For bombers, usually the entire crew would decide on a name and the artwork to be put on their a/c, however, in some cases the pilot made the decision. On some, a crew member would do the actual artwork and painting, and some squadrons or groups had their own "resident" artists that would do the work for everyone. Some of the artists were very talented. I'm not sure what (if any) regulations existed then regarding positioning or subject matter, but whatever regs there may have been, they were not followed or enforced very closely. Most commanders at the time knew that the art was a morale-booster for the crews. Scantily clothed or nude female figures were very popular. Most art was painted on the nose section of an aircraft, but some was put on other parts (such as the engines or fuselage). There was one famous example of a B-24 named "The Dragon And His Tail", on which the artwork stretched from the nose to the tail of the a/c. After the war, the Air Force came out with some restrictions on subject matter (ie-nudity), so nose art nowadays is a lot tamer and more regulated than it was during WW2.
Here are a couple of interesting articles about military nose art (the second is about the RAF): http://parentseyes.arizon...ynoseart/overview3.htm http://www.dailymail.co.u...end-women-Muslims.html