Date: 201203
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Climb
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Hydraulic System Lines; Connectors; Fittings
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Human-Machine Interface
Anomaly: Aircraft Equipment Problem Critical
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Flight Crew Returned To Departure Airport; Flight Crew Landed As Precaution; General Maintenance Action; General Declared Emergency
Contributing factors: Aircraft; Human Factors
Primary problem: Aircraft

Narrative: Preflight and takeoff were all normal. Since we were heavy; about 160;000 LBS. on a short runway; we needed TOGA power and I kept the flaps out a little longer to ensure we could meet the altitude restrictions in the SID. After a couple more minutes we received an ECAM message HYD Pump Low Pressure Green. I told the First Officer to take care of the ECAM; I had the aircraft and radios and put on autopilot 1. The First Officer turned off the Green Pump and it appeared that the PTU was taking care of Green Pressure. After a bit of discussion; we sent Dispatch a message to call us. Dispatcher called and talked with the First Officer. We went into a holding pattern at FL190. At this point we started getting some occasional ECAM's and it appeared as though the PTU was not keeping the Green System above 2;700 PSI. The Yellow System was also indicating an overheat. We determined that the PTU was cavitating because the Green quantity was gone. This was confirmed when a PTU low pressure ECAM illuminated and we turned off the PTU. The Yellow System overheat went away and the hydraulic system seemed stable. The First Officer had been trying to talk with Maintenance but never could get a clear frequency; and ended up just dropping the phone patch. Dispatch agreed that we should return. We declared an emergency called Flight Attendants; made PAs; and the First Officer started on the ECAM. We felt like we were not in a hurry at this point and it would help to go slow and burn off some gas. We worked our way down to 10;000 FT in the holding pattern while the First Officer ran through the ECAM. We told Company and ATC we would need to stop straight ahead as we had no nose wheel steering. We completed the ECAM. We made one PA to the passengers; reviewed all the failed systems and told Approach we were ready. Our weight was 154;000. The First Officer cranked the gear down [Landing Gear Gravity Extension] with the checklist and we slowed to 210 about 10 miles out. We started putting flaps out early and were fully configured prior to the marker. All checklists were completed and we landed with a sink rate of 300-400 FPM. Landing was uneventful. We stopped the aircraft just short of Runway 09 and Tower told us to make a right. We reminded them that we had no nose wheel steering and could not turn the aircraft. We started the APU and shutdown the engines. A tug did come out to tow us to the Terminal; but the tug driver thought the gear doors might scrap and we asked a mechanic to come out and check. After a while the mechanic made it out to the aircraft and felt it was OK to tow in and we went slowly to the gate. There were no human factors. Dispatch; the First Officer; and all the ATC members were helpful and supportive.




Synopsis: A320 Captain experiences an ECAM message HYD Pump Low Pressure Green. The pump is turned off and initially the PTU appears to be maintaining Green system pressure. While holding at FL190 a PTU low pressure ECAM is annunciated along with a Yellow system overheat. The PTU is turned of and the crew elects to return to the departure airport after the Yellow system cools.