Lieutenant Walter Carl Simon (1890–1971) was a World War I flying ace credited with eight aerial victories.

Flying a Bristol F.2 Fighter for the British, he and his observer scored five victories on the single day of 30 July 1918; he thus became the first American "ace in a day".

When the war ended, he went to Lima, Peru, where he was promoted to the rank of 1st Lieutenant and became Vice-director of the Naval Flying School at Ancon, headed by Captain Juan Swayne Leguia, former RAF pilot in World War I and son of Augusto B. Leguia, president of Peru.

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