Narrative:

We lost the 'a' system hydraulic engine pump and 'a' system fluid down to the standpipe. We still had good system 'a' pressure. We declared an emergency and did the QRH. Approach and landing uneventful. The equipment followed us to the gate. Callback conversation with reporter revealed the following information: the reporter stated the 'a' system engine driven hydraulic pump low pressure warning illuminated and the pump was feathered. The reporter said 'a' pressure was normal as the 'a' electric pump was operating and the hydraulic quantity was dropping slowly and was not depleted until parking at the gate. The reporter said when the cowling was opened the pump case was found to be cracked.

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Original NASA ASRS Text

Title: A B737-300 ON APCH AT 12000 FT DECLARED AN EMER DUE TO 'A' HYD ENG DRIVEN PUMP FAILURE CAUSED BY A CRACKED PUMP CASE.

Narrative: WE LOST THE 'A' SYS HYD ENG PUMP AND 'A' SYS FLUID DOWN TO THE STANDPIPE. WE STILL HAD GOOD SYS 'A' PRESSURE. WE DECLARED AN EMER AND DID THE QRH. APCH AND LNDG UNEVENTFUL. THE EQUIP FOLLOWED US TO THE GATE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE 'A' SYS ENG DRIVEN HYD PUMP LOW PRESSURE WARNING ILLUMINATED AND THE PUMP WAS FEATHERED. THE RPTR SAID 'A' PRESSURE WAS NORMAL AS THE 'A' ELECTRIC PUMP WAS OPERATING AND THE HYD QUANTITY WAS DROPPING SLOWLY AND WAS NOT DEPLETED UNTIL PARKING AT THE GATE. THE RPTR SAID WHEN THE COWLING WAS OPENED THE PUMP CASE WAS FOUND TO BE CRACKED.

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.