Narrative:

During an ILS runway 1L approach at airport at approximately 2500 ft MSL, I noticed a flicker of the elevator low pressure light. About 30 seconds later, I noticed another flicker of the same light. I pressed-to-test the warning light, received a valid test, and crosschecked the hydraulic system 'a' quantity gauge on the so's panel. The 'a' system hydraulic quantity read less than .5 gallons. At this point, I commanded a missed approach to take time to run the appropriate checklists, and evaluate the situation. We retracted flaps to 15 degrees from 30 degrees, left the gear down, and coordinated with ATC to fly a pattern while we completed our duties. We still had system 'a' hydraulic pressure and quantity, so we ran the company 'hydraulic leak or loss checklist.' after determining that the leak was not in the spoiler system, we complied with the checklist and shut off the 'a' system hydraulic pumps. The #1 'a pump was operating with normal pressure. The #2 'a' pump experienced fluctuations in pressure, and was off. We completed the normal in-range and before landing checklist, and told ATC we were ready for the ILS runway 1L. After initiating the approach, the first officer as PF called for flaps 30 degrees. I positioned the handle to 30 degrees, but with quantity so low, we had pressure fluctuations on the remaining pump. I had the so switch off the #1 a pump, and positioned the flaps to 30 degrees using the alternate flap extension system. Because of the length of time required to extend the flaps via the alternate flap master switch, by the time the flaps were in landing position, we were near 1000 ft AGL, and I felt it necessary to go back forward to monitor the approach. This is where I may have made a mistake in procedure. If pressure was not normal, the appropriate landing flap confign would have been flaps 15 degrees. After landing the aft, I could not move the tiller and did not have nosewheel steering. The bottom line is that I may have landed the aircraft in the wrong flap position, but can't say positively one way or the other. In hindsight, we were in an unusual position. We had an operable 'a' system, but not enough so to drive the flaps to 30 degrees hydraulically. After completing the hydraulic leak or loss checklist, we thought we were back to a normal sequence of in-range and before landing checklists. This affected my decision to land with flaps 30 degrees. In the future, I think one more circuit in a delay pattern would have been appropriate after attempting to lower the flaps to 30 degrees hydraulically.

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Original NASA ASRS Text

Title: A B727-200 EXPERIENCED AN 'A' SYS HYD LEAK. THE CAPT ELECTED TO LAND WITH 30 DEGS FLAPS EXTENDED ELECTRICALLY EVEN THOUGH FLAPS 15 DEGS WOULD HAVE BEEN PROCEDURALLY CORRECT.

Narrative: DURING AN ILS RWY 1L APCH AT ARPT AT APPROX 2500 FT MSL, I NOTICED A FLICKER OF THE ELEVATOR LOW PRESSURE LIGHT. ABOUT 30 SECONDS LATER, I NOTICED ANOTHER FLICKER OF THE SAME LIGHT. I PRESSED-TO-TEST THE WARNING LIGHT, RECEIVED A VALID TEST, AND XCHKED THE HYD SYS 'A' QUANTITY GAUGE ON THE SO'S PANEL. THE 'A' SYS HYD QUANTITY READ LESS THAN .5 GALLONS. AT THIS POINT, I COMMANDED A MISSED APCH TO TAKE TIME TO RUN THE APPROPRIATE CHKLISTS, AND EVALUATE THE SIT. WE RETRACTED FLAPS TO 15 DEGS FROM 30 DEGS, LEFT THE GEAR DOWN, AND COORDINATED WITH ATC TO FLY A PATTERN WHILE WE COMPLETED OUR DUTIES. WE STILL HAD SYS 'A' HYD PRESSURE AND QUANTITY, SO WE RAN THE COMPANY 'HYD LEAK OR LOSS CHKLIST.' AFTER DETERMINING THAT THE LEAK WAS NOT IN THE SPOILER SYS, WE COMPLIED WITH THE CHKLIST AND SHUT OFF THE 'A' SYS HYD PUMPS. THE #1 'A PUMP WAS OPERATING WITH NORMAL PRESSURE. THE #2 'A' PUMP EXPERIENCED FLUCTUATIONS IN PRESSURE, AND WAS OFF. WE COMPLETED THE NORMAL IN-RANGE AND BEFORE LNDG CHKLIST, AND TOLD ATC WE WERE READY FOR THE ILS RWY 1L. AFTER INITIATING THE APCH, THE FO AS PF CALLED FOR FLAPS 30 DEGS. I POSITIONED THE HANDLE TO 30 DEGS, BUT WITH QUANTITY SO LOW, WE HAD PRESSURE FLUCTUATIONS ON THE REMAINING PUMP. I HAD THE SO SWITCH OFF THE #1 A PUMP, AND POSITIONED THE FLAPS TO 30 DEGS USING THE ALTERNATE FLAP EXTENSION SYS. BECAUSE OF THE LENGTH OF TIME REQUIRED TO EXTEND THE FLAPS VIA THE ALTERNATE FLAP MASTER SWITCH, BY THE TIME THE FLAPS WERE IN LNDG POS, WE WERE NEAR 1000 FT AGL, AND I FELT IT NECESSARY TO GO BACK FORWARD TO MONITOR THE APCH. THIS IS WHERE I MAY HAVE MADE A MISTAKE IN PROC. IF PRESSURE WAS NOT NORMAL, THE APPROPRIATE LNDG FLAP CONFIGN WOULD HAVE BEEN FLAPS 15 DEGS. AFTER LNDG THE AFT, I COULD NOT MOVE THE TILLER AND DID NOT HAVE NOSEWHEEL STEERING. THE BOTTOM LINE IS THAT I MAY HAVE LANDED THE ACFT IN THE WRONG FLAP POS, BUT CAN'T SAY POSITIVELY ONE WAY OR THE OTHER. IN HINDSIGHT, WE WERE IN AN UNUSUAL POS. WE HAD AN OPERABLE 'A' SYS, BUT NOT ENOUGH SO TO DRIVE THE FLAPS TO 30 DEGS HYDRAULICALLY. AFTER COMPLETING THE HYD LEAK OR LOSS CHKLIST, WE THOUGHT WE WERE BACK TO A NORMAL SEQUENCE OF IN-RANGE AND BEFORE LNDG CHKLISTS. THIS AFFECTED MY DECISION TO LAND WITH FLAPS 30 DEGS. IN THE FUTURE, I THINK ONE MORE CIRCUIT IN A DELAY PATTERN WOULD HAVE BEEN APPROPRIATE AFTER ATTEMPTING TO LOWER THE FLAPS TO 30 DEGS HYDRAULICALLY.

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.