opter ▁was ▁initially ▁power ed ▁by ▁a ▁ ▁engine ▁( V 1 ) ▁and ▁then ▁a ▁ ▁engine ▁( V 2 ) — both ▁by ▁Walter ▁Mik ron . ▁ ▁It ▁first ▁fle w ▁in ▁ 1 9 4 3 , ▁and ▁was ▁captured ▁with ▁V 4 ▁at ▁Z ell ▁am ▁See . ▁ ▁V 3 : ▁ ▁The ▁second ▁W NF ▁ 3 4 2 ▁had ▁a ▁larger ▁rot or ▁and ▁was ▁destroyed ▁during ▁testing . V 4 : ▁ ▁The ▁last ▁unit ▁produced ▁was ▁a ▁two - se at ▁variant ▁with ▁new ▁collect ive ▁and ▁cy clic ▁controls . ▁ ▁After ▁ 2 5 ▁flight ▁hours ▁it ▁was ▁captured ▁by ▁United ▁States ▁forces ▁and ▁on ▁July ▁ 1 9 , ▁ 1 9 4 5 , ▁sh ipped ▁to ▁the ▁US ▁under ▁Operation ▁L ust y ▁on ▁HMS ▁Re aper ▁( D 8 2 ). ▁ ▁Spec ifications ▁( V 4 ) ▁ ▁See ▁also ▁ ▁References ▁ ▁Vert ical ▁R ew ind : ▁Spo ils ▁of ▁War ▁ ▁External ▁links ▁Dob l hoff ▁W NF ▁ 3 4 2 ▁V 4 ▁in ▁scale ▁of ▁ 1 ▁: ▁ 1 1 ▁as ▁shown ▁in ▁the ▁Hel ic opter ▁Museum ▁of ▁B ück eb urg ▁ ▁Category : 1 9 4 0 s ▁Aust rian ▁experimental ▁aircraft ▁Category : 1 9 4 0 s ▁Aust rian ▁hel ic op ters ▁Category : A ircraft ▁first ▁flow n ▁in ▁ 1 9 4 3 ▁W NF ▁ 3 4 2 ▁Category : T