▁at ▁the ▁University ▁of ▁Berlin . ▁However , ▁he ▁was ▁ex mat ric ulated ▁for ▁not ▁undert aking ▁his ▁studies . ▁ ▁After ▁ 1 8 8 0 ▁he ▁developed ▁concepts ▁for ▁a ▁space ▁vehicle ▁based ▁on ▁the ▁principle ▁of ▁rep ulsion . ▁His ▁two - stage ▁vehicle ▁was ▁designed ▁to ▁be ▁driven ▁by ▁a ▁series ▁of ▁dynam ite ▁explos ions . ▁Since ▁it ▁was ▁to ▁be ▁taken ▁al o ft ▁by ▁way ▁of ▁a ▁car rier ▁vehicle , ▁he ▁designed ▁a ▁hel ic opter ▁as ▁early ▁as ▁ 1 8 8 4 . ▁ ▁On ▁ 2 7 ▁May ▁ 1 8 9 1 , ▁he ▁gave ▁a ▁public ▁speech ▁at ▁the ▁Berlin ▁Phil harm ony ▁in ▁which ▁he ▁introduced ▁his ▁concept ▁of ▁a ▁gal actic ▁vehicle ▁( Wel ten fahr zeug ). ▁In ▁July ▁ 1 9 0 1 ▁the ▁ma iden ▁flight ▁of ▁his ▁hel ic opter ▁took ▁place ▁in ▁Berlin - Sch ö ne berg , ▁which ▁probably ▁was ▁the ▁first ▁heav ier - than - air ▁motor - dri ven ▁flight ▁carrying ▁humans . ▁A ▁movie ▁covering ▁the ▁event ▁was ▁taken ▁by ▁Max ▁Sk lad an ow sky , ▁but ▁it ▁remains ▁lost . ▁ ▁In ▁ 1 9 0 2 , ▁G ans wind t ▁was ▁accused ▁of ▁fra ud ▁and ▁arrested ▁because ▁he ▁had ▁added ▁a ▁safety ▁bar ▁to ▁his ▁vehicle ▁to ▁prevent ▁it ▁from ▁rolling . ▁After ▁sp ending ▁eight ▁weeks ▁in ▁pre - tri al ▁cust ody ▁he ▁was ▁released ▁after ▁a ▁flight ▁demonstr