Lieutenant Commander Takahashi, Kakuichi
The dive-bombers of the First Attack Wave were under the command of Lieutenant Commander Takahashi who also led the 15th Attack Unit of Aichi D3A1 Vals from Shokaku. The signal to attack was to be given by Lieutenant Commander Mitsuo Fuchida (Fuchida, Mitsuo), flying with 1st Attack Unit. At 0740 on 7 December, as they closed with Oahu, Fuchida concluded that they had not been observed by the Americans and fired the single flare that indicated that the torpedo bombers should go in first. It soon became clear that the fighters had not seen the signal, so he fired a second flare. Takahashi saw both and took this to mean that the dive-bombers he led were to hit the airfields at once. The confusion made little difference to the outcome.
You can find out more about Japanese airmen in World War II in the following Osprey books: