Narrative:

Departed cvg with hydraulic pump 1B deferred. In climb, hydraulic fluid quantity indication was fluctuating +/-100%. Spoke with maintenance controller. They indicated it was probably a bad indication. The pressure indication and temperature remained normal. Because we thought it was only an indication problem, we continued to acy and agreed to have maintenance look at the system on the ground. At cruise, approximately 10 mins later, we received a hydraulic #1 low pressure caution message. We ran the QRH (calling for a diversion to the nearest suitable airport), briefed the flight attendant, briefed the passenger, and again conferred with dispatch and maintenance. We were all in agreement to the diversion. Descent, approach and landing were uneventful.

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Original NASA ASRS Text

Title: CRJ200 CREW HAD AN EICAS CAUTION MESSAGE 'HYD #1 LOW PRESSURE.' THEY DIVERTED TO THE NEAREST SUITABLE ARPT, AS INDICATED IN THE QRH CHKLIST.

Narrative: DEPARTED CVG WITH HYD PUMP 1B DEFERRED. IN CLB, HYD FLUID QUANTITY INDICATION WAS FLUCTUATING +/-100%. SPOKE WITH MAINT CTLR. THEY INDICATED IT WAS PROBABLY A BAD INDICATION. THE PRESSURE INDICATION AND TEMP REMAINED NORMAL. BECAUSE WE THOUGHT IT WAS ONLY AN INDICATION PROB, WE CONTINUED TO ACY AND AGREED TO HAVE MAINT LOOK AT THE SYS ON THE GND. AT CRUISE, APPROX 10 MINS LATER, WE RECEIVED A HYD #1 LOW PRESSURE CAUTION MESSAGE. WE RAN THE QRH (CALLING FOR A DIVERSION TO THE NEAREST SUITABLE ARPT), BRIEFED THE FLT ATTENDANT, BRIEFED THE PAX, AND AGAIN CONFERRED WITH DISPATCH AND MAINT. WE WERE ALL IN AGREEMENT TO THE DIVERSION. DSCNT, APCH AND LNDG WERE UNEVENTFUL.

Data retrieved from NASA's ASRS site as of July 2007 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.