Narrative:

ECAM message yellow system hydraulic level low plus rain/metal sound near door 2R. Declared emergency and advised dispatch. Diverted to mco and delayed approach 15 mins for WX. Used medium autobrakes due to #2 reverser inoperative. Uneventful landing and taxi. Emergency equipment secured. Callback conversation with reporter revealed the following information: the day of the event reporter had arrived at the aircraft when it was parked on the ramp. There was a noticeable hydraulic leak, as evidenced by fluid on the ramp. That leak was repaired. The aircraft developed another leak later while in-flight, in a totally different area. A hydraulic coupling failed and allowed fluid to leak into the power transfer unit inside the aircraft. This was in the 'yellow' system, driven by the #2 engine. Reporter commented that the A320 'appears to have a problem' with hydraulic leaks, and/or failures. The noise that the PIC had initially reported was from another source entirely. The pressure outflow valve has 2 vent ducts. One is from the cabin via the lavatory. The other is via the aft cargo compartment. The clamp holding the duct from the cabin came loose near the '2R' door. The loud clicking sound reported was this clamp vibrating against the airframe.

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Original NASA ASRS Text

Title: ACFT EQUIP PROB MALFUNCTION ON A320 CREATES NEED FOR DIVERSION TO ALTERNATE. EMER DECLARED.

Narrative: ECAM MESSAGE YELLOW SYS HYD LEVEL LOW PLUS RAIN/METAL SOUND NEAR DOOR 2R. DECLARED EMER AND ADVISED DISPATCH. DIVERTED TO MCO AND DELAYED APCH 15 MINS FOR WX. USED MEDIUM AUTOBRAKES DUE TO #2 REVERSER INOP. UNEVENTFUL LNDG AND TAXI. EMER EQUIP SECURED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE DAY OF THE EVENT RPTR HAD ARRIVED AT THE ACFT WHEN IT WAS PARKED ON THE RAMP. THERE WAS A NOTICEABLE HYD LEAK, AS EVIDENCED BY FLUID ON THE RAMP. THAT LEAK WAS REPAIRED. THE ACFT DEVELOPED ANOTHER LEAK LATER WHILE INFLT, IN A TOTALLY DIFFERENT AREA. A HYD COUPLING FAILED AND ALLOWED FLUID TO LEAK INTO THE PWR TRANSFER UNIT INSIDE THE ACFT. THIS WAS IN THE 'YELLOW' SYS, DRIVEN BY THE #2 ENG. RPTR COMMENTED THAT THE A320 'APPEARS TO HAVE A PROB' WITH HYD LEAKS, AND/OR FAILURES. THE NOISE THAT THE PIC HAD INITIALLY RPTED WAS FROM ANOTHER SOURCE ENTIRELY. THE PRESSURE OUTFLOW VALVE HAS 2 VENT DUCTS. ONE IS FROM THE CABIN VIA THE LAVATORY. THE OTHER IS VIA THE AFT CARGO COMPARTMENT. THE CLAMP HOLDING THE DUCT FROM THE CABIN CAME LOOSE NEAR THE '2R' DOOR. THE LOUD CLICKING SOUND RPTED WAS THIS CLAMP VIBRATING AGAINST THE AIRFRAME.

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.