I was reading the most recent Model Aviation about how to trim your plane for down thrust. I think I have the opposite and need up thrust. Has anyone ever had this?

The plane (GP Super Skybolt, OS FS 91, 13X8 prop, 10 lbs, cg is good) requires up trim to fly level (haven't measured it, but I would say 3/16" to 1/4" deflection up). Does this mean that the engine is always pulling down and therefore need up trim? Being a bi-wing, I know there are incidences interacting, but when the throttle is cut it immidiately heads down, very little float.

Thanks,