What's the name of this bird?
Hmmmm... the only one I can think of fitting at least in part your description would be the golden oriole (Oriolus oriolus). 

I say partly because it definitely is not 2-3 times a blackbird, could be slightly bigger, but on average it is the same size. Also it sounds extremely unlikely that you have spotted it in early March in Zurich, as they should be in Southern Africa right now.

Image, from Wikipedia:



I could not find anything else fitting your description in my field guide (Mullarney &amp; Svensson - Birds of Europe)