Unique observation aircraft with crew nacelle mounted to one side of the fuselage and tractor engine on the centre-section of the monoplane wing. Small number operated on the Eastern Front from late 1941.
No the BMW 801 engine gave this bird unpleasant vibrations, original it used BMW 132 engine (with 132 engine it flew well) but the RLM (German Air Ministry) wanted more power so Blohm & Voss gave it the BMW 801 engine wich didn't go well. Since the had the Fw 189 they stoped production of the Bv 141.
It could be that its weird shape was meant to baffle and confuse its enemies, giving it time to snoop before vanishing over the horizon! Seriously, though, its performance specs are quite superior those of its competition, the FW189. It was more than 40 mph faster, could fly 10,000 feet higher, and had a range about twice that of its rival. Like de Jong, I've also read that it was the need for the BMW801A-0 engine, used by higher priority combat aircraft, that held it back.
It shouldn't be criticized for its looks. It was intended to be asymmetrical as an observation plane. If it flies well, then the Germans have achieved another engineering marvel in the field of aviation during the war years.
It was a great airplane, in spite of its weird looks it flew great, the torque of the propellor offsetting the asymmetric configuration (some feat of engineering). It had an even larger field of view than its rival, the Focke-Wulf FW189.
The main reason it lost the competition with the FW is that the twin-engined twin-boom FW189 could use 2 relatively weak (French-built) engines, while the single-engined BV141 required a much more powerful engine, and those were reserved for the single-engine fighters like the Me109 and the FW190.