What was found
(CAN) DURING MAINT WALK AROUND, COMPLETE PROP BLADE DE-ICE BOOT HAD DEPARTED AC. AIRFRAME, ENG WAS INSPECTED FOR FOD DAMAGE FROM DE-ICE BOOT. DETERMINED THAT BOOT HAD SEPERATED FROM AC DAY BEFORE DURING TAKE-OFF. PILOT FELT VIBRATION FROM LT ENG DURING RUN-UP, DURING TAKE-OFF FLUCTUATION OF TORQUE INDICATION FOR ENG, THEN SETTLED OUT FOR REST OF FLIGHT BECAUSE VIBRATION WENT AWAY. FURTHER INVESTIGATION SHOWS DE-ICE BOOT WAS THROWN ALONG LENGTH OF BLADE THEN DEPARTED AC (RUBBER STREAKS OUT TO BLADE TIP). GLUE ON BLADE LOOKED TO BE IN NORMAL CONDITION, NO DETERIORATION OF GLUE BED. DETERMINED 2 BOOTS ON THAT PROP WERE CHANGED, CANNOT DETERMINE IF IT WAS ONE OF REPLACED BOOTS.