Meet a Bücker Bü 181 Bestmann. “Bestmann” is the German for Best Man. Funny, that, especially as a Bestmann isn’t what you think, but rather a crew member on board ship.
Also funny is that this particular one isn’t actually a 181 at all but a licence built variant made in Sweden by Hägglunds, now part of defence contractor BAE.
Interesting how small single engined planes haven’t changed much in appearance in the past eighty years.
Also interesting is that the engine is mounted inverted, with the crankcase on top.