Narrative:

We arrived from ZZZ and had an aircraft change to go to ZZZ1. As the arriving captain was getting off the aircraft; he told me that the #1 hydraulic quantity indicating system had been deferred. I checked the synoptic page and saw the reservoir icon was black; not yellow as the fcom says an inoperative system is. I checked the MEL and called maintenance to have a mechanic check the actual reservoir level. The mechanic discovered that the reservoir was in fact empty. He found the leak in the vicinity of the #1 engine-driven hydraulic pump. The indicating system was working correctly. Over-the-phone deferrals may not be in the best interest of safety.

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Original NASA ASRS Text

Title: A CRJ-200 OUTBOUND CAPTAIN NOTICES THE DEFERRED # 1 HYDRAULIC QUANTITY INDICATING SYSTEM IS NOT INOP; THE HYD RESERVOIR WAS ACTUALLY EMPTY.

Narrative: WE ARRIVED FROM ZZZ AND HAD AN ACFT CHANGE TO GO TO ZZZ1. AS THE ARRIVING CAPT WAS GETTING OFF THE ACFT; HE TOLD ME THAT THE #1 HYD QUANTITY INDICATING SYS HAD BEEN DEFERRED. I CHKED THE SYNOPTIC PAGE AND SAW THE RESERVOIR ICON WAS BLACK; NOT YELLOW AS THE FCOM SAYS AN INOP SYS IS. I CHKED THE MEL AND CALLED MAINT TO HAVE A MECH CHK THE ACTUAL RESERVOIR LEVEL. THE MECH DISCOVERED THAT THE RESERVOIR WAS IN FACT EMPTY. HE FOUND THE LEAK IN THE VICINITY OF THE #1 ENG-DRIVEN HYD PUMP. THE INDICATING SYS WAS WORKING CORRECTLY. OVER-THE-PHONE DEFERRALS MAY NOT BE IN THE BEST INTEREST OF SAFETY.

Data retrieved from NASA's ASRS site as of May 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.