What was found
(CAN) AFTER 7 DAYS OF SITTING OUTSIDE IN THE RAIN THE ACFT WAS STARTED UP FOR REPOSITIONING. ONCE THE ACFT WAS AT FLIGHT IDLE, A AIRFRAME VIBRATION WAS FELT & THE TAKEOFF WAS ABORTED & THE ENG WAS SHUT DOWN. UPON INSPECTION THE TAIL ROTOR BLADE WAS INSPECTED & DETERMINED TO BE THE CAUSE OF THE VIBRATION. THERE WAS EVIDENCE THAT WATER HAD PENETRATED THE TAIL ROTOR BLADE ASSEMBLY & WAS CAUSING THE SUDDEN OUT OF BALANCE. THE WATER THAT TRAVELED THROUGH THE INSIDE OF THE BLADE STARTED TO EXIT THE BLADE BY WAY OF FORMING A BUBBLE UNDER THE SURFACE PAINT. THE BLADE WAS REMOVED FROM SERVICE & IS BEING SENT TO THE MFG FOR FURTHER INSPECTION.