iled ▁by ▁am ateurs . ▁The ▁outcome ▁was ▁the ▁ ▁OK ▁d ing hy , ▁which ▁went ▁on ▁to ▁be ▁a ▁classic ▁design , ▁became ▁an ▁IS AF ▁International ▁Class ▁in ▁ 1 9 7 4 ▁and ▁is ▁still ▁used ▁in ▁international ▁competition . ▁The ▁ 5 0 th ▁anni versary ▁of ▁the ▁design ▁of ▁the ▁OK ▁d ing hy ▁was ▁marked ▁by ▁the ▁largest ▁ever ▁OK ▁D ing hy ▁World ▁Championships ▁held ▁at ▁Ł eb a ▁on ▁the ▁Polish ▁coast ▁in ▁July ▁ 2 0 0 7 . ▁ ▁Kn ud ▁O ls en ▁died ▁aged ▁ 9 0 ▁on ▁ 3 1 ▁August ▁ 2 0 1 0 ▁in ▁his ▁h omet own ▁Band holm . ▁ ▁References ▁ ▁S ources ▁Ok dia : ▁Kn ud ▁O ls en ▁OK ▁D ing hy ▁World ▁Championships , ▁Leb a , ▁Poland ▁S ail world . com : ▁L arg est ▁ever ▁OK ▁D ing hy ▁World ▁Championships ▁Welcome ▁to ▁the ▁OK ▁cor al , ▁Dans k ▁Ok j ol le ▁Kl ub ▁ ▁See ▁also ▁OK ▁D ing hy ▁ ▁Category : Bo at ▁and ▁ship ▁design ers ▁Category : 1 9 1 9 ▁birth s ▁Category : 2 0 1 0 ▁death s ▁Category : Dan ish ▁y acht ▁design ers <0x0A> </s> ▁Na um ▁Alexand rov ich ▁Bab ae v ▁( , ▁IP A : ▁n ɐ ′ um ▁ ɐ l ʲ ɪ k ′ s andr ɐ v it ɕ ▁b ɐ ′ ba ʲ ef ) ▁is