Narrative:

We got an ECAM yellow system low pressure. Sent message to maintenance controller via ACARS. During the descent, we lost yellow system. We informed ATC that we had a hydraulic problem and needed a little extra time in configuring the airplane. When we lost yellow system we were busy in the descent and looking up landing performance calculations regarding loss of yellow system. ATC asked us if we would like to have the equipment standing by and we said yes. However, a miscom took place between approach and tower. Tower had thought we lost total hydraulics when we only really lost 1 system. Hindsight, I should have sent a message to dispatch regarding the hydraulic failure and the request for equipment, but we were so busy talking to ATC, flight attendants and looking up performance, that it became a low priority since we were descending into ZZZ. I did do a cabin advisory and spoke to the passenger about our problem. Upon landing, called station operations and called dispatch to clear up the miscom.

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Original NASA ASRS Text

Title: AN AIRBUS 320 LOST YELLOW HYD SYS PRESSURE AND QUANTITY. ADVISED MAINT AND ATC. TWR BELIEVED ALL HYDS LOST WITH THE DECLARED EMER. ACFT ONLY LOST 1 OF 3 SYS.

Narrative: WE GOT AN ECAM YELLOW SYS LOW PRESSURE. SENT MESSAGE TO MAINT CTLR VIA ACARS. DURING THE DSCNT, WE LOST YELLOW SYS. WE INFORMED ATC THAT WE HAD A HYD PROB AND NEEDED A LITTLE EXTRA TIME IN CONFIGURING THE AIRPLANE. WHEN WE LOST YELLOW SYS WE WERE BUSY IN THE DSCNT AND LOOKING UP LNDG PERFORMANCE CALCULATIONS REGARDING LOSS OF YELLOW SYS. ATC ASKED US IF WE WOULD LIKE TO HAVE THE EQUIP STANDING BY AND WE SAID YES. HOWEVER, A MISCOM TOOK PLACE BTWN APCH AND TWR. TWR HAD THOUGHT WE LOST TOTAL HYDS WHEN WE ONLY REALLY LOST 1 SYS. HINDSIGHT, I SHOULD HAVE SENT A MESSAGE TO DISPATCH REGARDING THE HYD FAILURE AND THE REQUEST FOR EQUIP, BUT WE WERE SO BUSY TALKING TO ATC, FLT ATTENDANTS AND LOOKING UP PERFORMANCE, THAT IT BECAME A LOW PRIORITY SINCE WE WERE DSNDING INTO ZZZ. I DID DO A CABIN ADVISORY AND SPOKE TO THE PAX ABOUT OUR PROB. UPON LNDG, CALLED STATION OPS AND CALLED DISPATCH TO CLR UP THE MISCOM.

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.