Spy Chart - Found in Downed Japanese Attack Plane

Takeo Yoshikawa provided detailed charts to the Japanese Imperial High Command, as depicted in this recovered document. The U.S. Navy Historical Center provides more information on this official U.S. Navy photograph:

Recovered from a Japanese Navy aircraft downed during the attack on Pearl Harbor, 7 December 1941.

The chart identifies ship mooring locations and is entitled (at upper left): "Report on positions of enemy fleet at anchorage A". Code at left represents ship types (Letter figures are written in katakana: "A" - battleship; "I" - aircraft carrier; "E" - cruiser; "U" - special service ship; "O" - light cruiser. Mooring locations are coded with paired katakana figures or with katakana plus an arabic numeral, but do not specifically identify the ship types moored there.

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