Narrative:

We were in cruise flight at FL310 approximately 50 miles north of ZZZ when we received an idg caution message. After approximately 5 seconds the message disappeared. We then selected the electrical page on the mfd and noted that the #2 idg icon was rapidly changing color back and forth between green and yellow. Since we were not currently receiving an idg caution message; we elected to contact maintenance via radio. While we were waiting for maintenance; the idg 2 caution message reappeared. We immediately executed the idg 2 abnormal procedures checklist; which called for disconnecting the idg and descending to FL300 and starting the APU. We then elected to descend to FL240 to provide for improved APU cooling. We informed maintenance and had dispatch amend our flight release to reflect our new fuel consumption at FL240. Approximately 20 minutes later we received an APU oil temperature caution message. We performed the abnormal procedures checklist and because the APU generator was essential; we declared an emergency and diverted to ZZZ1; which at that point was 40 miles behind us. The diversion occurred without incident. Contract maintenance at ZZZ1 informed us that the APU was 2 1/2 quarts low on oil. The APU oil was serviced; the idg was deferred; and we continued to destination without incident. On the return flight; we once again received an APU oil temperature caution message. Because the APU generator was essential; we once again declared an emergency as required by the abnormal procedures checklist and diverted to ZZZ2; which was directly below us. While we were in ZZZ2; it was determined that I would time out and so I was released to rest. The remainder of the crew continued the flight with a new first officer and a new aircraft. The next day; I ferried that same aircraft with a different captain to ZZZ3 without incident.

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Original NASA ASRS Text

Title: CRJ-200 FLT CREW HAS FAILURE OF THE IDG AND APU; DECLARES EMER AND DIVERTS FOR LNDG.

Narrative: WE WERE IN CRUISE FLIGHT AT FL310 APPROXIMATELY 50 MILES NORTH OF ZZZ WHEN WE RECEIVED AN IDG CAUTION MESSAGE. AFTER APPROXIMATELY 5 SECONDS THE MESSAGE DISAPPEARED. WE THEN SELECTED THE ELECTRICAL PAGE ON THE MFD AND NOTED THAT THE #2 IDG ICON WAS RAPIDLY CHANGING COLOR BACK AND FORTH BETWEEN GREEN AND YELLOW. SINCE WE WERE NOT CURRENTLY RECEIVING AN IDG CAUTION MESSAGE; WE ELECTED TO CONTACT MAINTENANCE VIA RADIO. WHILE WE WERE WAITING FOR MAINTENANCE; THE IDG 2 CAUTION MESSAGE REAPPEARED. WE IMMEDIATELY EXECUTED THE IDG 2 ABNORMAL PROCEDURES CHECKLIST; WHICH CALLED FOR DISCONNECTING THE IDG AND DESCENDING TO FL300 AND STARTING THE APU. WE THEN ELECTED TO DESCEND TO FL240 TO PROVIDE FOR IMPROVED APU COOLING. WE INFORMED MAINTENANCE AND HAD DISPATCH AMEND OUR FLIGHT RELEASE TO REFLECT OUR NEW FUEL CONSUMPTION AT FL240. APPROXIMATELY 20 MINUTES LATER WE RECEIVED AN APU OIL TEMP CAUTION MESSAGE. WE PERFORMED THE ABNORMAL PROCEDURES CHECKLIST AND BECAUSE THE APU GENERATOR WAS ESSENTIAL; WE DECLARED AN EMERGENCY AND DIVERTED TO ZZZ1; WHICH AT THAT POINT WAS 40 MILES BEHIND US. THE DIVERSION OCCURRED WITHOUT INCIDENT. CONTRACT MAINTENANCE AT ZZZ1 INFORMED US THAT THE APU WAS 2 1/2 QUARTS LOW ON OIL. THE APU OIL WAS SERVICED; THE IDG WAS DEFERRED; AND WE CONTINUED TO DEST WITHOUT INCIDENT. ON THE RETURN FLIGHT; WE ONCE AGAIN RECEIVED AN APU OIL TEMP CAUTION MESSAGE. BECAUSE THE APU GENERATOR WAS ESSENTIAL; WE ONCE AGAIN DECLARED AN EMERGENCY AS REQUIRED BY THE ABNORMAL PROCEDURES CHECKLIST AND DIVERTED TO ZZZ2; WHICH WAS DIRECTLY BELOW US. WHILE WE WERE IN ZZZ2; IT WAS DETERMINED THAT I WOULD TIME OUT AND SO I WAS RELEASED TO REST. THE REMAINDER OF THE CREW CONTINUED THE FLIGHT WITH A NEW FIRST OFFICER AND A NEW AIRCRAFT. THE NEXT DAY; I FERRIED THAT SAME AIRCRAFT WITH A DIFFERENT CAPTAIN TO ZZZ3 WITHOUT INCIDENT.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.