B737-300 crew had an 'a' hydraulic system failure on approach to ord.

Attributes
ACN	608374
Time
Date	200402
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : bdf.vortac
State Reference	IL
Altitude	msl single value : 23000
Aircraft 1
Controlling Facilities	artcc : zau.artcc
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	descent : approach descent : intermediate altitude
Route In Use	arrival star : bradford
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	608374
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 130 flight time total : 10000 flight time type : 900
ASRS Report	608375
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : hyd qty indicator other flight crewa other flight crewb
Resolutory Action	flight crew : landed in emergency condition flight crew : declared emergency
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

During descent into ord on bradford arrival, first officer noticed 'a' hydraulic quantity decreasing -- settled at approximately 1/8 quart. Shortly thereafter, engine #1 'a' hydraulic system 'low pressure' light illuminated. Accomplished 'a' hydraulic system quantity or pressure loss irregular checklist. Declared an emergency with ATC. Accomplished phone patch with dispatch and maintenance controller to review indications/actions taken and to ensure tow equipment available upon landing. Briefed with flight attendants and advised them of situation and that this was a 'cabin advisory' -- that we planned to stop on the runway and be towed to the gate if all other indications were normal. Accomplished ILS to runway 14R at ord to full stop. All fire equipment and maintenance personnel were standing by. After a visual check of aircraft exterior by emergency and maintenance personnel, we were towed to the gate where we were met by maintenance and in-flight personnel. Debriefed with flight attendants and contacted dispatch to debrief event. Dispatch and maintenance controller support was excellent. Ord ATC from center to approach to tower and ground were very helpful. Also, crew coordination and support was excellent, including a deadheading B737-300 pilot who assisted in accomplishing checklists, and another who verified gear was down and locked using cabin view ports.

Original NASA ASRS Text

Title: 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.

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.