[2] On December 7, 1941, Tyler was a first lieutenant in the Army Air Corps serving as the Executive Officer of the 78th Pursuit Squadron, based at Pearl Harbor.

That morning he was assigned duty as the Officer In Charge of the partly activated Pearl Harbor Intercept Center.

His duties were to assist the controller in ordering American planes to intercept unknown aircraft approaching Pearl Harbor.

However the operator, working in training mode, failed to make clear the size of the formation even though it was larger than anything they had ever seen, and he did not pass on an alarm of "attack imminent”.

Following an investigation by a Naval Board of Inquiry in August 1942,[3] it was determined that Tyler had been assigned to the Information Center with little or no training, no supervision, and no staff with which to work.