A CL65 IN CLB AT 3500 FT DECLARED AN EMER AND DIVERTED DUE TO L ENG FAN BLADE DAMAGE FROM ICE INGESTION.

Narrative

WE DEPARTED ZZZ AT XA00 ON JAN/SUN/04; AFTER ENCOUNTERING 2 PREVIOUS CANCELLATIONS DUE TO FREEZING DRIZZLE AND ICE PELLETS. THE ACFT WAS EXPOSED TO THIS WX ON THE RAMP AREA FOR ABOUT 4 HRS PRIOR TO OUR DEP. THE ACFT WAS COVERED WITH ICE. WE TAXIED OUT FOR DEP DURING ALMOST VFR CONDITIONS. ZZZ WAS 800 FT OVCST; VISIBILITY 6 MI AND MIST. WE REQUESTED A 'THOROUGH' DEICING WITH TYPE 1 FLUID AND THEN DEPARTED. UPON ENTERING IMC CONDITIONS; WE TURNED ON WING ANTI-ICE. AFTER FLAP RETRACTION; WE HEARD A LOUD BANG OR POP; FOLLOWED BY A HVY BUZZING OR VIBRATION. WE COULD NOT POSITIVELY DETERMINE THE NATURE OF THE PROB; BUT SUSPECTED AN ENG MALFUNCTION. WE DECLARED AN EMER AND LANDED WITHOUT FURTHER INCIDENT ON RWY 36R. AFTER LNDG; WE SAW 3 HEAVILY DAMAGED FAN BLADES IN THE #1 OR L ENG. WE SUSPECT THAT ICE WAS STILL ADHERING TO THE ACFT OR POSSIBLY INSIDE THE ENG COWLING AND WENT UNDETECTED BY THE DEICING CREW. THIS ICE DISLODGED IN FLT AND WAS INGESTED. WE DON'T KNOW FOR SURE SINCE THE ENGS ARE TAIL MOUNTED AND YOU CAN'T SEE THE BOTTOM OF THE INLET DURING WALKAROUND -- ASSUMING OF COURSE THE DAMAGE WAS FROM ICE AND NOT SOMETHING ELSE.