Narrative:

System B hydraulic fluid level kept creeping down; we noticed it just before our final descent. As a precaution we asked center to tell our destination airport that we needed the long runway. We weren't sure if the fluid level was going to drain out as the flaps came out. Initially; we did not declare an emergency since nothing was wrong as of yet. Tower declared an emergency for us. We configured the jet early enough that we would have had enough time to declare an emergency and manually extend the flaps on a long final. Fluid level went to 60% at full flap extension; and held there. We landed uneventfully had airport rescue and fire fighters look over the jet for any leaks and we taxied to the gate.

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Original NASA ASRS Text

Title: A B737-800 crew did not declare an emergency after notifying ARTCC about a potential hydraulic fluid loss. The destination airport ATC declared the emergency for them when the longest runway was requested. An uneventful landing followed.

Narrative: System B Hydraulic fluid level kept creeping down; we noticed it just before our final descent. As a precaution we asked Center to tell our destination airport that we needed the long runway. We weren't sure if the fluid level was going to drain out as the flaps came out. Initially; we did not declare an emergency since nothing was wrong as of yet. Tower declared an emergency for us. We configured the jet early enough that we would have had enough time to declare an emergency and manually extend the flaps on a long final. Fluid level went to 60% at full flap extension; and held there. We landed uneventfully had Airport Rescue and Fire Fighters look over the jet for any leaks and we taxied to the gate.

Data retrieved from NASA's ASRS site as of April 2012 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.