What was found
(CAN) HELICOPTER WAS FLYING WITH EXTERNAL LOAD WHEN THE PILOT FELT A (BUMP) IN THE CONTROLS. THE WEATHER WAS DETERIOATING WHERE HE WAS OPERATING SO HE RETURNED TO THE STAGING AREA. THE PILOT INSPECTED THE BLADES AFTER SHUTDOWN AND FOUND A 4.5 INCH CRACK 19 INCHES OUTBOARD FROM THE ROOT END, ONE BLADE ON THE BOTTOM STARTING FROM THE TRAILING EDGE. THE BLADE WAS REMOVED AND REPLACED WITH A SERVICEABLE UNIT AND THE AIRCRAFT RETURNED TO SERVICE. THE SAFETY BOARD WAS NOTIFIED AND THE UNSERVICEABLE BLADE WAS SENT TO THEM FOR INSPECTION.