The longer hulls suffer increased skin friction,and have frontal area-based Cd 0.07.
The short,'Tin Bubble' at bottom is optimized for pressure/friction drag,with Cd 0.04.
The reason 'short' hulls aren't produced is do to limited payload,directional stability issues,and air-sickness for the crews.And as a camera or weapons platform it would be virtually impossible to hit a target with the ship listing,yawing, and pitching all over the place.
