Narrative:

Hydraulic pressure gauge on #1 system went to '0' psi. Temperature and quantity were normal. Ran hydraulic pressure low light illuminated checklist in QRH. Had QRH out for further checklists if necessary. Reviewed hydraulic quantity leak or loss checklist. A short time later hydraulic system #1 quantity low lights came on and hydraulic quantity slowly started to decrease. Ran memory items for hydraulic quantity leak or loss. Ran and complied with hydraulic system #1 leak or loss checklist procedure. Departed rvsm due to no autoplt. After all checklist procedures had been accomplished and completed; we returned to mem with no further problems and uneventful landing.

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Original NASA ASRS Text

Title: DC-10 LOST #1 HYD QUANTITY AND PRESSURE. FLT CREW DSNDED TO DEPART RVSM AIRSPACE AND CONTINUED TO DEST.

Narrative: HYD PRESSURE GAUGE ON #1 SYS WENT TO '0' PSI. TEMP AND QUANTITY WERE NORMAL. RAN HYD PRESSURE LOW LIGHT ILLUMINATED CHKLIST IN QRH. HAD QRH OUT FOR FURTHER CHKLISTS IF NECESSARY. REVIEWED HYD QUANTITY LEAK OR LOSS CHKLIST. A SHORT TIME LATER HYD SYS #1 QUANTITY LOW LIGHTS CAME ON AND HYD QUANTITY SLOWLY STARTED TO DECREASE. RAN MEMORY ITEMS FOR HYD QUANTITY LEAK OR LOSS. RAN AND COMPLIED WITH HYD SYS #1 LEAK OR LOSS CHKLIST PROC. DEPARTED RVSM DUE TO NO AUTOPLT. AFTER ALL CHKLIST PROCS HAD BEEN ACCOMPLISHED AND COMPLETED; WE RETURNED TO MEM WITH NO FURTHER PROBS AND UNEVENTFUL LNDG.

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.