B737-300 CREW HAD AN 'A' HYD SYS FAILURE ON APCH TO ORD.

Narrative

DURING DSCNT INTO ORD ON BRADFORD ARR; FO NOTICED 'A' HYD QUANTITY DECREASING -- SETTLED AT APPROX 1/8 QUART. SHORTLY THEREAFTER; ENG #1 'A' HYD SYS 'LOW PRESSURE' LIGHT ILLUMINATED. ACCOMPLISHED 'A' HYD SYS QUANTITY OR PRESSURE LOSS IRREGULAR CHKLIST. DECLARED AN EMER WITH ATC. ACCOMPLISHED PHONE PATCH WITH DISPATCH AND MAINT CTLR TO REVIEW INDICATIONS/ACTIONS TAKEN AND TO ENSURE TOW EQUIP AVAILABLE UPON LNDG. BRIEFED WITH FLT ATTENDANTS AND ADVISED THEM OF SIT AND THAT THIS WAS A 'CABIN ADVISORY' -- THAT WE PLANNED TO STOP ON THE RWY AND BE TOWED TO THE GATE IF ALL OTHER INDICATIONS WERE NORMAL. ACCOMPLISHED ILS TO RWY 14R AT ORD TO FULL STOP. ALL FIRE EQUIP AND MAINT PERSONNEL WERE STANDING BY. AFTER A VISUAL CHK OF ACFT EXTERIOR BY EMER AND MAINT PERSONNEL; WE WERE TOWED TO THE GATE WHERE WE WERE MET BY MAINT AND INFLT PERSONNEL. DEBRIEFED WITH FLT ATTENDANTS AND CONTACTED DISPATCH TO DEBRIEF EVENT. DISPATCH AND MAINT CTLR SUPPORT WAS EXCELLENT. ORD ATC FROM CTR TO APCH TO TWR AND GND WERE VERY HELPFUL. ALSO; CREW COORD AND SUPPORT WAS EXCELLENT; INCLUDING A DEADHEADING B737-300 PLT WHO ASSISTED IN ACCOMPLISHING CHKLISTS; AND ANOTHER WHO VERIFIED GEAR WAS DOWN AND LOCKED USING CABIN VIEW PORTS.