A CANADAIR CL65 IN CRUISE AT FL200 EXPERIENCED THE R ENG OIL PRESSURE DECREASE AND OIL LEVEL WARNING. DECLARED AN EMER AND SHUT DOWN R ENG. ON EMER DSCNT OVERSHOT INTXN CLRNC.

Narrative

DURING PREFLT WALKAROUND; THE FO DISCOVERED OIL LEAKING FROM THE AFT EQUIP BAY. MAINT FOUND THE SOURCE OF THE OIL LEAK TO BE IN THE OIL SVCING LINE FOR THE #2 (R) ENG. THE ENG OIL SVCING SYS WAS THEN DEFERRED. THE R ENG OIL QUANTITY WAS FOUND TO BE ADEQUATE. THE MAINT SIGNOFF WAS COMPLETED AND THE FLT DEPARTED FOR CVG 2 HRS LATE. TKOF; CLB AND CRUISE TO CVG WERE UNEVENTFUL. SOME MI W OF INDIANAPOLIS; WE DISCOVERED THE R ENG OIL PRESSURE FLUCTUATING BTWN 40-60 PSI. AT FL200 WE RECORDED THE #2 OIL PRESSURE BTWN 30-40 PSI AND I RADIOED MAINT CTL TO ADVISE OF THE PROB. DURING DISCUSSION WITH MAINT; THE R OIL PRESSURE WARNING MESSAGE CAME ON BRIEFLY. I ADVISED MAINT AND SAID I WOULD CALL THEM BACK AS IT LOOKED LIKE WE MIGHT HAVE TO SHUT DOWN THE ENG. THE OIL PRESSURE WARNING CLRED AND WE ASKED CINCINNATI APCH CTL FOR PRIORITY HANDLING TO THE ARPT; DESCRIBED OUR SIT AND SAID THAT WE WOULD PREFER TO LAND WITH BOTH ENGS OPERATING. WHILE ON THE VISUAL APCH; 5 MI L BASE FOR RWY 36L; GEAR DOWN; FLAPS 45 DEGS AND LNDG CHK COMPLETE; I STARTED THE TURN TO FINAL WHEN #2 OIL PRESSURE DROPPED TO 19 PSI AND WE GOT THE 'ENG OIL' AURAL WARNING. WE DECIDED TO SHUT DOWN THE #2 ENG. AT THIS TIME WE DECLARED AN EMER. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THE OIL LEAK THAT WAS DISCOVERED BY THE FO AND WAS DEFERRED PRIOR TO DEP WAS IN THE REMOTE OIL SVC SYS FOR THE R ENG. THE RPTR SAID THE R ENG OIL SVC VALVE FAILED TO OPEN AND FORCED ENG OIL BACK DOWN THE DEFERRED OIL SVC LINE WHICH WAS CRACKED; CAUSING THE LOSS OF ENG OIL.