How to throw a spinning card

[Leptyx]

EDIT : solved, thanks :)

 

[CWatters]

Depending on the shape of the object the lift on the front and rear halves isn't the same and this would cause it to pitch up/down if it wasn't spinning. As I understand it the spinning converts this pitch effect into a roll effect.

I believe this effect is worse for flat plate like objects and less for frissbees like shapes that are designed to balance the lift in the fore/aft plane... but I'm no expert!

Perhaps read up on the physics of the frissbee?