I just read an interview from 1975 with Kurt Tank. He stated that a radial engine was the choice from the beginning, but the original radial had problems with two of the back row pistons overheating. The radial was chosen because being air cooled, it could be hit and not lose the entire engine.

Other indications of the foresight used in its design; from the beginning, they realized that the overall weight would climb drastically, so they designed the landing gear for twice the original loading.

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Lord, let me be the person my dog thinks I am.