Narrative:

Climbing out of FL180 the aircraft developed indications for loss of yellow system hydraulic pressure. As we had briefed; the first officer accomplished the ECAM action while I advised ATC and declared an emergency. We discussed all the ramifications of an overweight landing with flight control problems and made an uneventful approach and landing. Airline personnel met the aircraft after exiting clear of the runway and checked the aircraft for hydraulic leaks and the brakes for damage. After receiving their clearance; we taxied to the gate without further incident. Supplemental information from acn 705263: climbing through FL180; in vicinity of intersection; ECAM displayed 'yellow hydraulic pressure low.' captain was flying and directed ECAM action. That was completed and followed by the QRH which directed the 'loss of yellow hydraulic' checklist. Since flight controls were involved; captain elected to return for overweight landing. He declared an emergency and requested crash fire rescue equipment to meet us. Normal checklists were accomplished and we were cleared. Captain executed a slightly flat approach which resulted in not exceeding 100 FPM upon touchdown. We taxied off and crash fire rescue equipment checked the exterior of aircraft and brakes. Maintenance arrived and cleared us to taxi back to the ramp.

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Original NASA ASRS Text

Title: A HVY COMMERCIAL TRANSPORT EXPERIENCED HYD SYS FAILURE DURING CLB. THEY DECLARED AN EMER AND RETURNED TO LAND AT DEP ARPT.

Narrative: CLBING OUT OF FL180 THE ACFT DEVELOPED INDICATIONS FOR LOSS OF YELLOW SYS HYD PRESSURE. AS WE HAD BRIEFED; THE FO ACCOMPLISHED THE ECAM ACTION WHILE I ADVISED ATC AND DECLARED AN EMER. WE DISCUSSED ALL THE RAMIFICATIONS OF AN OVERWT LNDG WITH FLT CTL PROBS AND MADE AN UNEVENTFUL APCH AND LNDG. AIRLINE PERSONNEL MET THE ACFT AFTER EXITING CLR OF THE RWY AND CHKED THE ACFT FOR HYD LEAKS AND THE BRAKES FOR DAMAGE. AFTER RECEIVING THEIR CLRNC; WE TAXIED TO THE GATE WITHOUT FURTHER INCIDENT. SUPPLEMENTAL INFO FROM ACN 705263: CLBING THROUGH FL180; IN VICINITY OF INTXN; ECAM DISPLAYED 'YELLOW HYD PRESSURE LOW.' CAPT WAS FLYING AND DIRECTED ECAM ACTION. THAT WAS COMPLETED AND FOLLOWED BY THE QRH WHICH DIRECTED THE 'LOSS OF YELLOW HYD' CHKLIST. SINCE FLT CTLS WERE INVOLVED; CAPT ELECTED TO RETURN FOR OVERWT LNDG. HE DECLARED AN EMER AND REQUESTED CFR TO MEET US. NORMAL CHKLISTS WERE ACCOMPLISHED AND WE WERE CLRED. CAPT EXECUTED A SLIGHTLY FLAT APCH WHICH RESULTED IN NOT EXCEEDING 100 FPM UPON TOUCHDOWN. WE TAXIED OFF AND CFR CHKED THE EXTERIOR OF ACFT AND BRAKES. MAINT ARRIVED AND CLRED US TO TAXI BACK TO THE RAMP.

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.