Narrative:

We were flying at FL370 talking to center when we got a rsvr light on the left hydraulic system. We checked the status page and saw 0.48 and decreasing. I was the pilot flying so my co-pilot ran the 757 hydraulic qty checklist and the 757 hydraulic system press checklist to see what was affected. After completing the checklists I noticed the yoke deflected 2 units to the left. We were both very concerned with the deflection of the ailerons so we decided to declare an emergency and land. I proceeded to contact dispatch and maintenance to let them know what was happening. I then contacted the purser to fill her in. We landed without incident and taxied to the gate.

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Original NASA ASRS Text

Title: A B757-200 flight crew experienced loss of left hydraulic system; and after noticing the yoke was displaced 2 units they declared an emergency; contacted Dispatch and Maintenance; then diverted.

Narrative: We were flying at FL370 talking to Center when we got a RSVR light on the left HYD system. We checked the status page and saw 0.48 and decreasing. I was the pilot flying so my co-pilot ran the 757 HYD QTY checklist and the 757 HYD SYS PRESS checklist to see what was affected. After completing the checklists I noticed the yoke deflected 2 units to the left. We were both very concerned with the deflection of the ailerons so we decided to declare an emergency and land. I proceeded to contact Dispatch and Maintenance to let them know what was happening. I then contacted the purser to fill her in. We landed without incident and 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.