Narrative:

The first officer completed the preflight and did not note any discrepancies with the aircraft. We departed a few minutes early. Forty- six minutes into the flight we received an ECAM hgd G rsvr lo lvl. We completed the appropriate check list. The check list had us shutdown the green system. At that point the green reservoir showed just above empty. We notified maintenance control and dispatch of the condition of the aircraft and asked them where they would like us to land as the aircraft was fine in flight; however performance of the aircraft was not sufficient to land at our destination. While we were awaiting the decision from dispatch; as to our alternate; I informed the a flight attendant that we had a mechanical condition which would require a precautionary landing. I asked her to review her procedures and told her I would get back to her when we had more information. Dispatch and maintenance suggested ZZZ2 as the alternate. I was against this as they had ninety degree cross winds gusting above twenty knots. With possibly no brakes and steering and loss of some flight controls I asked for a different airport. After going back and forth with dispatch and maintenance control; it was decided that we would make a precautionary landing in ZZZ. The first officer and I reviewed all of the procedures and decided; for performance; in case of a go around a flaps three landing was called for. Also; in reviewing flight operations manual (F.O.M.); we decided that the aircraft situation was 'urgent' and did not meet the definition of an emergency. Therefore; an emergency was not declared. Approaching the top of descent point I called the a flight attendant and once again briefed her that a precautionary landing was being made and told her I would be making the announcement to the passengers in five minutes. I waited five minutes and read the precautionary landing announcement from the F.O.M. To the passengers. The ECAM procedure for the aircraft condition allowed for us to try and restore the green system to lower the gear. We successfully attempted this procedure and lowered the gear. However; due to the small amount of hydraulic fluid remaining it was determined to not be safe to try and taxi to the gate. We landed on the runway and came to a stop. The fire crews inspected the aircraft and found a puddle of fluid under the left engine. The maintenance crew came to the aircraft they requested and we delivered through the first officer's window the gear pins. The maintenance crew secured the gear and we were towed to the gate. It was found that the hydraulic pressure valve had blown an 'O' ring and was leaking fluid when under pressure.

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Original NASA ASRS Text

Title: After suffering the loss of the Green Hydraulic System an A320 flight crew opted to divert to an airport more suitable for landing with possibly compromised braking and or steering.

Narrative: The First Officer completed the preflight and did not note any discrepancies with the aircraft. We departed a few minutes early. Forty- six minutes into the flight we received an ECAM HGD G RSVR LO LVL. We completed the appropriate check list. The check list had us shutdown the Green System. At that point the green reservoir showed just above empty. We notified Maintenance Control and Dispatch of the condition of the aircraft and asked them where they would like us to land as the aircraft was fine in flight; however performance of the aircraft was not sufficient to land at our destination. While we were awaiting the decision from Dispatch; as to our alternate; I informed the A Flight Attendant that we had a mechanical condition which would require a precautionary landing. I asked her to review her procedures and told her I would get back to her when we had more information. Dispatch and Maintenance suggested ZZZ2 as the alternate. I was against this as they had ninety degree cross winds gusting above twenty knots. With possibly no brakes and steering and loss of some flight controls I asked for a different airport. After going back and forth with Dispatch and Maintenance Control; it was decided that we would make a precautionary landing in ZZZ. The First Officer and I reviewed all of the procedures and decided; for performance; in case of a go around a flaps three landing was called for. Also; in reviewing Flight Operations Manual (F.O.M.); we decided that the aircraft situation was 'Urgent' and did not meet the definition of an Emergency. Therefore; an emergency was not declared. Approaching the top of descent point I called the A Flight Attendant and once again briefed her that a precautionary landing was being made and told her I would be making the announcement to the passengers in five minutes. I waited five minutes and read the precautionary landing announcement from the F.O.M. to the passengers. The ECAM procedure for the aircraft condition allowed for us to try and restore the Green System to lower the gear. We successfully attempted this procedure and lowered the gear. However; due to the small amount of hydraulic fluid remaining it was determined to not be safe to try and taxi to the gate. We landed on the runway and came to a stop. The fire crews inspected the aircraft and found a puddle of fluid under the left engine. The Maintenance crew came to the aircraft they requested and we delivered through the First Officer's window the gear pins. The Maintenance crew secured the gear and we were towed to the gate. It was found that the hydraulic pressure valve had blown an 'O' ring and was leaking fluid when under pressure.

Data retrieved from NASA's ASRS site as of April 2012 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.