Narrative:

During a flight from mco to bos, on descent on the orw arrival, we had a standby hydraulic low quantity light come on. We followed boeing's procedures. Shortly thereafter, we noted the 'a' system hydraulic quantity had dropped to 1 gallon (normal capacity is 4 gallons). It was at this time that we, again, conferred with dispatch/maintenance, and they informed us that we might lose total 'a' system hydraulics, and that nosewheel steering might not be available, as well as limited reverse thrust, and braking. It was at this point that we opted to declare an emergency with bos approach control. The approach and landing were uneventful. We were able to taxi to the gate under our own power, with some minimal loss of nosewheel steering as we approached the gate area.

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Original NASA ASRS Text

Title: A B737-200 CAPT RPTED THE LOSS OF 'A' HYD SYS WHILE ON THE NORWICH 2 ARR INTO BOS. AN EMER WAS DECLARED AND THE FLT LANDED UNEVENTFULLY.

Narrative: DURING A FLT FROM MCO TO BOS, ON DSCNT ON THE ORW ARR, WE HAD A STANDBY HYD LOW QUANTITY LIGHT COME ON. WE FOLLOWED BOEING'S PROCS. SHORTLY THEREAFTER, WE NOTED THE 'A' SYS HYD QUANTITY HAD DROPPED TO 1 GALLON (NORMAL CAPACITY IS 4 GALLONS). IT WAS AT THIS TIME THAT WE, AGAIN, CONFERRED WITH DISPATCH/MAINT, AND THEY INFORMED US THAT WE MIGHT LOSE TOTAL 'A' SYS HYDS, AND THAT NOSEWHEEL STEERING MIGHT NOT BE AVAILABLE, AS WELL AS LIMITED REVERSE THRUST, AND BRAKING. IT WAS AT THIS POINT THAT WE OPTED TO DECLARE AN EMER WITH BOS APCH CTL. THE APCH AND LNDG WERE UNEVENTFUL. WE WERE ABLE TO TAXI TO THE GATE UNDER OUR OWN PWR, WITH SOME MINIMAL LOSS OF NOSEWHEEL STEERING AS WE APCHED THE GATE AREA.

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.