As commenter DougN pointed out earlier, Ferdiand Porsche's design for the Tiger tank was passed over for a design by Henschel. However, an armor-hungry Wehrmacht did end up with a retooled version of Porsche's Tiger in tank-killer guise. The Ferdinand had its air-cooled Porsche powerplants yanked and replaced with a pair of 300hp Maybach engines used to power electric motors. Fuel economy was an astonishing 1/4mpg. Fitted with a Krupp 88mm gun, the Ferdinands fared poorly at Kursk, where nearly half the force was lost.
The surviving vehicles were brought back to Germany, upgraded and by Hitlerian decree, took on the name Elefant. Only two examples survive today. One captured at Kursk by the Russians and one taken by the Americans at Anzio. We assume the Cayenne hybrid will be more efficient, even if it may be a white Elefant.
Elefant [Wikipedia]
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