Narrative:

Flight was operations normal until approximately 20 mins out of yyz. I noticed the system #2 hydraulic quantity was at 39. We both watched the quantity intently from that point on. We discussed possible required checklists if the quantity were to continue to drop to an annunciated low hydraulic quantity condition. The quantity slowly dropped to 35. We then were given an efc for yyz, which would have delayed our arrival at yyz by 30 mins. We also were given holding instructions at waypoint 'linning' 26 mi from yyz on the arrival. As we entered holding, the quantity dropped quickly from 35 to 31. I decided to inform ATC of our situation and I declared an emergency. Yyz ATC cleared us direct to the field for approach runway 6R. We did all normal checklists and landing was uneventful. We canceled crash fire rescue equipment after clearing runway and taxied to the gate. Total time from declaration of the emergency to landing was approximately 10 mins. Yyz and approach control were very helpful in handling our aircraft with priority. Though we never got a system #2 hydraulic quantity indication of the MFDU panel, I believe it was necessary to get our aircraft on the ground as soon as possible, not knowing whether we had an actual hydraulic leak or not.

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Original NASA ASRS Text

Title: AN ACR F100 FLC HAD A LOSS OF HYD FLUID IN THE #2 SYS AND THEY DECLARED AN EMER.

Narrative: FLT WAS OPS NORMAL UNTIL APPROX 20 MINS OUT OF YYZ. I NOTICED THE SYS #2 HYD QUANTITY WAS AT 39. WE BOTH WATCHED THE QUANTITY INTENTLY FROM THAT POINT ON. WE DISCUSSED POSSIBLE REQUIRED CHKLISTS IF THE QUANTITY WERE TO CONTINUE TO DROP TO AN ANNUNCIATED LOW HYD QUANTITY CONDITION. THE QUANTITY SLOWLY DROPPED TO 35. WE THEN WERE GIVEN AN EFC FOR YYZ, WHICH WOULD HAVE DELAYED OUR ARR AT YYZ BY 30 MINS. WE ALSO WERE GIVEN HOLDING INSTRUCTIONS AT WAYPOINT 'LINNING' 26 MI FROM YYZ ON THE ARR. AS WE ENTERED HOLDING, THE QUANTITY DROPPED QUICKLY FROM 35 TO 31. I DECIDED TO INFORM ATC OF OUR SIT AND I DECLARED AN EMER. YYZ ATC CLRED US DIRECT TO THE FIELD FOR APCH RWY 6R. WE DID ALL NORMAL CHKLISTS AND LNDG WAS UNEVENTFUL. WE CANCELED CFR AFTER CLRING RWY AND TAXIED TO THE GATE. TOTAL TIME FROM DECLARATION OF THE EMER TO LNDG WAS APPROX 10 MINS. YYZ AND APCH CTL WERE VERY HELPFUL IN HANDLING OUR ACFT WITH PRIORITY. THOUGH WE NEVER GOT A SYS #2 HYD QUANTITY INDICATION OF THE MFDU PANEL, I BELIEVE IT WAS NECESSARY TO GET OUR ACFT ON THE GND ASAP, NOT KNOWING WHETHER WE HAD AN ACTUAL HYD LEAK OR NOT.

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.