B727 crew had an 'a' system hydraulic failure.

Attributes
ACN	478017
Time
Date	200006
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : den.airport
State Reference	CO
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : d01.tracon tower : cle.tower
Operator	common carrier : air carrier
Make Model Name	B727-200
Operating Under FAR Part	Part 121
Flight Phase	descent : vacating altitude
Route In Use	arrival star : ns
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 140 flight time total : 9500 flight time type : 3000
ASRS Report	478017
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : multi engine
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment : tcas aircraft equipment other aircraft equipment : 1 other flight crewb
Resolutory Action	other
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

About 1 hour and 20 mins into our flight the flight engineer advised me that the 'a' system hydraulic volume was indicating zero. 'A' system pressure indicated normal. I asked the flight engineer to call maintenance control and advise them while I looked at the a system leak/loss checklist. Maintenance control told us they felt that we had an indication problem, but to watch for other indications. After a short time #1 system 'a' hydraulic low pressure light began to flicker on. I declared an emergency and we completed the 'a' system leak/loss checklist. We advised the flight attendants and briefed our passenger of our situation and our intentions. Landing was uneventful, but we had to be towed to the gate.

Original NASA ASRS Text

Title: B727 CREW HAD AN 'A' SYS HYD FAILURE.

Narrative: ABOUT 1 HR AND 20 MINS INTO OUR FLT THE FE ADVISED ME THAT THE 'A' SYS HYD VOLUME WAS INDICATING ZERO. 'A' SYS PRESSURE INDICATED NORMAL. I ASKED THE FE TO CALL MAINT CTL AND ADVISE THEM WHILE I LOOKED AT THE A SYS LEAK/LOSS CHKLIST. MAINT CTL TOLD US THEY FELT THAT WE HAD AN INDICATION PROB, BUT TO WATCH FOR OTHER INDICATIONS. AFTER A SHORT TIME #1 SYS 'A' HYD LOW PRESSURE LIGHT BEGAN TO FLICKER ON. I DECLARED AN EMER AND WE COMPLETED THE 'A' SYS LEAK/LOSS CHKLIST. WE ADVISED THE FLT ATTENDANTS AND BRIEFED OUR PAX OF OUR SIT AND OUR INTENTIONS. LNDG WAS UNEVENTFUL, BUT WE HAD TO BE TOWED TO THE GATE.

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.