Narrative:

After leveloff at FL280, noticed system 1 hydraulic quantity decreasing through 65%. 15 mins later, abeam cyyz, noted system 1 decreasing through 50%. Informed toronto center that we were going to divert into cyyz for a precautionary landing due hydraulic quantity decreasing. Descending through 8000 ft with toronto approach control, system 1 quantity low MFDU message and overhead panel light illuminated. Accomplished system 1 low quantity procedure, as well as alternate gear and flap extension. Was able to get gear doors closed. Declared emergency with approach control, landed runway 60R at cyyz and turned off on high speed taxiway and parked. Ground personnel informed us that unknown fluid was draining from #1 engine nacelle. Shut down both engines and was towed to gate.

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Original NASA ASRS Text

Title: AN ACR F100 FLC HAD THE SYS #1 HYD FLUID START LEAKING SO THEY DIVERTED AND LANDED.

Narrative: AFTER LEVELOFF AT FL280, NOTICED SYS 1 HYD QUANTITY DECREASING THROUGH 65%. 15 MINS LATER, ABEAM CYYZ, NOTED SYS 1 DECREASING THROUGH 50%. INFORMED TORONTO CTR THAT WE WERE GOING TO DIVERT INTO CYYZ FOR A PRECAUTIONARY LNDG DUE HYD QUANTITY DECREASING. DSNDING THROUGH 8000 FT WITH TORONTO APCH CTL, SYS 1 QUANTITY LOW MFDU MESSAGE AND OVERHEAD PANEL LIGHT ILLUMINATED. ACCOMPLISHED SYS 1 LOW QUANTITY PROC, AS WELL AS ALTERNATE GEAR AND FLAP EXTENSION. WAS ABLE TO GET GEAR DOORS CLOSED. DECLARED EMER WITH APCH CTL, LANDED RWY 60R AT CYYZ AND TURNED OFF ON HIGH SPD TXWY AND PARKED. GND PERSONNEL INFORMED US THAT UNKNOWN FLUID WAS DRAINING FROM #1 ENG NACELLE. SHUT DOWN BOTH ENGS AND WAS TOWED TO GATE.

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.