What was found
WHEN THE MECHANIC REMOVED THE COWLS OVER THE TAIL ROTOR DRIVE SHAFT AND OIL COOLER, HE DISCOVERED A CRACK, ABOUT 5 INCHES LONG, ON THE FUSELAGE DECK BELOW THE OIL COOLER BLOWER MOUNT. THE ACFT WAS GROUNDED AND IS AWAITING A TRAILER TO TAKE IT FOR REPAIRS. AFTER REMOVING OIL COOLER COWLING FOR MX, A CRACK ABOUT 5 INCHES LONG,ON THE LT SIDE OF THE DECK SKIN AT THE AFT OIL TANK MOUNT WAS NOTICED. ACFT WAS GROUNDED AT THAT TIME. STAGE OF OPERATION CRACK DISCOVERED- ACFT ON GROUND FOR MX.