Narrative:

On departure from bdl. Hydraulic fluid quantity gauge read just above the RF line. After takeoff, the usual decrease in quantity was noted for gear up and flaps retracted. During cruise, the quantity continued to slowly decrease and flight control and maintenance control were contacted via radio. As we continued to monitor the hydraulic quantity, we reviewed checklists we might have to use. We were overhead FL310 when the hydraulic fluid decreased below the balance line level of 1.8 gallons. We coordinated with flight control and maintenance to divert to atlanta. We initiated our descent into atlanta as a precautionary landing, but later declared an emergency with atl approach and requested runway 27R for runway length. While configuring with flaps 5 degrees (speed brakes retracted) and speed less than 200 KTS, the aircraft experienced a significant shuddering that lasted until the gear was extended. No asymmetry was noted and flaps 15 degrees was selected as a final flap setting. The landing was 500 pounds overweight (103.5) with a 50 FPM descent. We stopped on the runway to determine hydraulic quantity and brake pressure and then taxied clear. We saw the hydraulic quantity was now approximately 2.0 with good brake pressure and canceled the emergency. With extreme vigilance, we taxied to the gate and were met by maintenance and passenger service. Logbook write-ups were made for the hydraulic malfunction and the overweight landing.

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Original NASA ASRS Text

Title: A B737 CREW EXPERIENCED DECREASING HYD QUANTITY DURING FLT, LANDED AT ATL.

Narrative: ON DEP FROM BDL. HYD FLUID QUANTITY GAUGE READ JUST ABOVE THE RF LINE. AFTER TKOF, THE USUAL DECREASE IN QUANTITY WAS NOTED FOR GEAR UP AND FLAPS RETRACTED. DURING CRUISE, THE QUANTITY CONTINUED TO SLOWLY DECREASE AND FLT CTL AND MAINT CTL WERE CONTACTED VIA RADIO. AS WE CONTINUED TO MONITOR THE HYD QUANTITY, WE REVIEWED CHKLISTS WE MIGHT HAVE TO USE. WE WERE OVERHEAD FL310 WHEN THE HYD FLUID DECREASED BELOW THE BAL LINE LEVEL OF 1.8 GALLONS. WE COORDINATED WITH FLT CTL AND MAINT TO DIVERT TO ATLANTA. WE INITIATED OUR DSCNT INTO ATLANTA AS A PRECAUTIONARY LNDG, BUT LATER DECLARED AN EMER WITH ATL APCH AND REQUESTED RWY 27R FOR RWY LENGTH. WHILE CONFIGURING WITH FLAPS 5 DEGS (SPD BRAKES RETRACTED) AND SPD LESS THAN 200 KTS, THE ACFT EXPERIENCED A SIGNIFICANT SHUDDERING THAT LASTED UNTIL THE GEAR WAS EXTENDED. NO ASYMMETRY WAS NOTED AND FLAPS 15 DEGS WAS SELECTED AS A FINAL FLAP SETTING. THE LNDG WAS 500 LBS OVERWT (103.5) WITH A 50 FPM DSCNT. WE STOPPED ON THE RWY TO DETERMINE HYD QUANTITY AND BRAKE PRESSURE AND THEN TAXIED CLR. WE SAW THE HYD QUANTITY WAS NOW APPROX 2.0 WITH GOOD BRAKE PRESSURE AND CANCELED THE EMER. WITH EXTREME VIGILANCE, WE TAXIED TO THE GATE AND WERE MET BY MAINT AND PAX SVC. LOGBOOK WRITE-UPS WERE MADE FOR THE HYD MALFUNCTION AND THE OVERWT LNDG.

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.