On the morning of 7 December 1941 the SCR-270 radar at the Opana Radar Site on northern Oahu detected a large number of aircraft approaching from the north. This information was conveyed to Fort Shafter’s Intercept Center. The report was dismissed by Lieutenant Kermit Tyler who assumed that it was a scheduled flight of aircraft from the continental United States. The radar had in fact detected the first wave of Imperial Japanese Navy Air Service aircraft about to launch the Attack on Pearl Harbor.