Narrative:

While on a flight from iah to tpa, 75 NM north of tpa we noted a #1 'a' system hydraulic pump low pressure light. We elected to continue into tpa using the remaining pump to provide pressure. While on approach vectors within 10 NM of the field, as flaps were extended, the remaining hydraulic pump low pressure light came on and quantity in the 'a' system dropped to near zero. We declared an emergency with ATC and initiated the emergency hydraulic leak or loss checklist. As this was being accomplished, pressure again climbed to the normal range. We used this pressure to extend gear and flaps for landing and advised ATC that the emergency was terminated, reasoning that pressure remaining in the 'a' system would allow a safe landing and taxi in. After parking at the gate, our maintenance personnel informed us that this aircraft had experienced similar problems twice before within the preceding month; facts which we were unaware of since the appropriate log book pages had been removed, including the previous days which showed the same hydraulic pump had failed. Supplemental information from acn 81554. Callback conversation with reporter revealed the following: flight crew never had any problem and had realized gear and flaps would operate slow with only one pump. For that reason they had declared an emergency in case they lost the other pump. This is a recently merged line and the surviving handles the maintenance log in an odd fashion. All log sheets are removed daily and placed in a pouch at back of log book so they are difficult to find and utilize. Reporter felt like it might be done to make it hard for crew to check past maintenance history. On follow up flight crew found that maintenance after this repeat problem finally did some trouble shooting and found a leak in the upper rudder which was being sucked off by airflow leaving no telltale hydraulic stains. Reporter feels maintenance on merged airline isn't that good and not near what they had on former airline.

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Original NASA ASRS Text

Title: ACR LGT INCURRED LOSS OF HYDRUALIC PRESSURE AND FLUID CAUSED BY LEAK AND LOSS OF ONE PUMP.

Narrative: WHILE ON A FLT FROM IAH TO TPA, 75 NM N OF TPA WE NOTED A #1 'A' SYS HYDRAULIC PUMP LOW PRESSURE LIGHT. WE ELECTED TO CONTINUE INTO TPA USING THE REMAINING PUMP TO PROVIDE PRESSURE. WHILE ON APCH VECTORS WITHIN 10 NM OF THE FIELD, AS FLAPS WERE EXTENDED, THE REMAINING HYDRAULIC PUMP LOW PRESSURE LIGHT CAME ON AND QUANTITY IN THE 'A' SYS DROPPED TO NEAR ZERO. WE DECLARED AN EMER WITH ATC AND INITIATED THE EMER HYDRAULIC LEAK OR LOSS CHKLIST. AS THIS WAS BEING ACCOMPLISHED, PRESSURE AGAIN CLBED TO THE NORMAL RANGE. WE USED THIS PRESSURE TO EXTEND GEAR AND FLAPS FOR LNDG AND ADVISED ATC THAT THE EMER WAS TERMINATED, REASONING THAT PRESSURE REMAINING IN THE 'A' SYS WOULD ALLOW A SAFE LNDG AND TAXI IN. AFTER PARKING AT THE GATE, OUR MAINT PERSONNEL INFORMED US THAT THIS ACFT HAD EXPERIENCED SIMILAR PROBS TWICE BEFORE WITHIN THE PRECEDING MONTH; FACTS WHICH WE WERE UNAWARE OF SINCE THE APPROPRIATE LOG BOOK PAGES HAD BEEN REMOVED, INCLUDING THE PREVIOUS DAYS WHICH SHOWED THE SAME HYDRAULIC PUMP HAD FAILED. SUPPLEMENTAL INFO FROM ACN 81554. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: FLT CREW NEVER HAD ANY PROB AND HAD REALIZED GEAR AND FLAPS WOULD OPERATE SLOW WITH ONLY ONE PUMP. FOR THAT REASON THEY HAD DECLARED AN EMER IN CASE THEY LOST THE OTHER PUMP. THIS IS A RECENTLY MERGED LINE AND THE SURVIVING HANDLES THE MAINT LOG IN AN ODD FASHION. ALL LOG SHEETS ARE REMOVED DAILY AND PLACED IN A POUCH AT BACK OF LOG BOOK SO THEY ARE DIFFICULT TO FIND AND UTILIZE. RPTR FELT LIKE IT MIGHT BE DONE TO MAKE IT HARD FOR CREW TO CHK PAST MAINT HISTORY. ON FOLLOW UP FLT CREW FOUND THAT MAINT AFTER THIS REPEAT PROB FINALLY DID SOME TROUBLE SHOOTING AND FOUND A LEAK IN THE UPPER RUDDER WHICH WAS BEING SUCKED OFF BY AIRFLOW LEAVING NO TELLTALE HYDRAULIC STAINS. RPTR FEELS MAINT ON MERGED AIRLINE ISN'T THAT GOOD AND NOT NEAR WHAT THEY HAD ON FORMER AIRLINE.

Data retrieved from NASA's ASRS site as of August 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.