Narrative:

At cruise altitude FL350, we experienced a gradual loss of 'a' system hydraulics. Approximately el paso VOR, the third in command announced a loss of 'a' system hydraulic compared to block out quantity from iah. We blocked out with approximately 4 gals on the gauge and at the point of discovery was down to 1 1/2 gals. With the loss not getting any worse, or still at a gradual decrease, we reviewed procedures for total loss, which included manual gear extension. At approximately 3/4 gal of 'a' system hydraulic and on the arrival into phx, we declared an emergency and received priority into phx. After slowing to minimum gear and flap speeds, we lowered landing gear normally. Flaps also lowered to 15 degrees (normal landing flaps for loss or leak checklist). Landing was uneventful, with a normal taxi to ramp. We did not experience a total loss of 'a' system. Supplemental information from acn 345806: on post flight inspection hydraulic fluid was found on the starboard wing. Solid knowledge of aircraft system prevented the situation from degrading any further.

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Original NASA ASRS Text

Title: B727 FREIGHTER SUFFERS A SLOW LOSS OF FLUID IN 'A' HYD SYS ENRTE TO PHX. EMER DECLARED IN LNDG PROC PHX. COMPLETED SAFELY WITH MINIMUM FLUID LEFT.

Narrative: AT CRUISE ALT FL350, WE EXPERIENCED A GRADUAL LOSS OF 'A' SYS HYDS. APPROX EL PASO VOR, THE THIRD IN COMMAND ANNOUNCED A LOSS OF 'A' SYS HYD COMPARED TO BLOCK OUT QUANTITY FROM IAH. WE BLOCKED OUT WITH APPROX 4 GALS ON THE GAUGE AND AT THE POINT OF DISCOVERY WAS DOWN TO 1 1/2 GALS. WITH THE LOSS NOT GETTING ANY WORSE, OR STILL AT A GRADUAL DECREASE, WE REVIEWED PROCS FOR TOTAL LOSS, WHICH INCLUDED MANUAL GEAR EXTENSION. AT APPROX 3/4 GAL OF 'A' SYS HYD AND ON THE ARR INTO PHX, WE DECLARED AN EMER AND RECEIVED PRIORITY INTO PHX. AFTER SLOWING TO MINIMUM GEAR AND FLAP SPDS, WE LOWERED LNDG GEAR NORMALLY. FLAPS ALSO LOWERED TO 15 DEGS (NORMAL LNDG FLAPS FOR LOSS OR LEAK CHKLIST). LNDG WAS UNEVENTFUL, WITH A NORMAL TAXI TO RAMP. WE DID NOT EXPERIENCE A TOTAL LOSS OF 'A' SYS. SUPPLEMENTAL INFO FROM ACN 345806: ON POST FLT INSPECTION HYD FLUID WAS FOUND ON THE STARBOARD WING. SOLID KNOWLEDGE OF ACFT SYS PREVENTED THE SIT FROM DEGRADING ANY FURTHER.

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.