and another case of Irimi tenkan outside the dojo:
"Ueshiba Sensei's techniques are genuine, you know. They can be applied to anything, including financial, political or military matters. For example, the air strike against Pearl Harbor was a method of irimi tenkan. Because the Japanese bombers flew there in front of the American Air Force, the men at Pearl Harbor thought that they were American troops. That was irimi tenkan. I heard that the Japanese headquarters talked about applying this irimi tenkan in their tactics. "
Aikido Journal, http://www.aikidojournal.com/article?articleID=394