Robert-Richard Zapp (3 April 1904 – 17 July 1964) was a German U-boat commander in World War II. As commander of the Type IXC U-boat U-66, he sank sixteen ships on five patrols, for a total of 106,200 tons of Allied shipping, to become the 27th highest scoring U-Boat ace of World War II. He was also a recipient of the Knight's Cross of the Iron Cross (German: Ritterkreuz des Eisernen Kreuzes). The Knight's Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership.