Which U.S. military base detected the Japanese aircraft approaching Pearl Harbor before the attack?

The Opana Radar Station detected Japanese aircraft approaching Pearl Harbor before the attack. Two U.S. Army privates operating a mobile radar set at Opana Point noticed a large group of aircraft on the morning of December 7, 1941.

The operators reported the contact to an Army information center. Lieutenant Kermit Tyler, who was on duty there, mistakenly assumed the aircraft were a scheduled flight of American B-17 bombers and did not issue an effective warning.

The incident did not mean the attack could have been easily stopped. The radar operators had limited experience, and the system was still being tested and used only during certain hours. Opana Point is now associated with one of the most famous missed warnings in military history.