This paper presents a computational fluid dynamics approach to study the forces and moments generated on the parent body due to attached fins in marine vehicles and also the velocity profile behind the fins. The conservation equations of mass and momentum are solved with Finite Volume Method by use of the software FLUENT. The turbulence closure model used is k-ω SST (shear stress transport). The study is carried out for single fin at various angles of attack and four fins attached to a cylinder.