Narrative:

Had just leveled off about 200 NM east of ZZZ; EICAS left hydraulic quan amber message appeared. Status page showed .46 quantity in left system and RF displayed. Rsvr light on overhead panel was illuminated. We accomplished B757 QRH for hydraulic quantity for the left system. Nothing to do there; we began reviewing QRH for hydraulic system pressure (left only) in the event that this would occur. Aircraft was dispatched under an MEL for the center electric right press indication. This probably had nothing to do with our problem; although we did think that at this time our problem was only an indicator problem; as all other parameters; including left system hydraulic pressure were normal. About 10 minutes later we received a call from the number 2 flight attendant that numerous passengers were reporting fluid all over the right wing surface. This confirmed to us that we did indeed have a hydraulic leak. We declared an emergency with center and turned around to ZZZ. We were about 250 miles west of ZZZ at this time with about 33;000 pounds of fuel. When we were headed back to ZZZ; dispatch was informed via ACARS. Our previous review of QRH for system loss; confirmed that we would possibly be using alternate gear and flap extension if the normal and or ptu were ineffective. About 150 miles from ZZZ; the quantity had fallen to .21 system pressure was still good. I asked for a descent to FL180 in order to attempt to configure the aircraft for a normal landing before we lost all quantity and was down to depending on only the alternate methods. We were cleared to 16;000 ft. Slowed to about 235 KIAS and lowered the landing gear. It went down normally. Quantity and pressure remained as before. Slowed to 220 KIAS and lowered flaps 1. Normal operation; continued to slow as appropriate for flap speeds and attained flaps 20. We continued until about 100 miles from ZZZ and the quantity began falling; accompanied by an intermittent hydraulic engine pump indication. While the light was out; we configured to flaps 25 for a normal landing. After this; the engine pump light came on steady and then the sys press caution light illuminated. Accomplished QRH for the pump and for the pressure; only item remaining was to turn off l electric hydraulic pump. As stated in the checklist; some spoilers would not work and roll rate might be reduced. We were flying with center autopilot engaged; and when the system failed; it was unable to control the roll axis. Autopilot was disconnected and it required 5 units left rudder trim and left aileron trim to maintain level flight. Nice to discover while still 25 minutes from landing. Flight attendant coordination was accomplished and the passengers were informed and reassured that a normal landing would occur. Hand flew an ILS to ZZZ [and] landed as previously configured with flaps 25. Weight had been conveniently burned down to about 196;000 pounds. Rolled to the end; used differential braking to clear and had maintenance meet us to pin the gear and tow in. Manual spoiler was planned and accomplished. Left reverser was inoperative. Turns out the number 2 spoiler actuator on the right wing; according to a preliminary report from maintenance after parking; had sprung a leak. Open for comments on decision to configure early. As far as my research indicates it did nothing to compound the problem. Fuel needed to be burned down anyway. Why wait to see if the backup methods would work? Always do in the sim; but who knows when they were tested on the real thing?

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Original NASA ASRS Text

Title: B757 flight crew experiences loss of hydraulic fluid from the left hydraulic system at FL380. The crew elects to return to the departure airport and extend the gear and flaps before the fluid is depleted. An overweight landing ensues.

Narrative: Had just leveled off about 200 NM east of ZZZ; EICAS L HYD Quan amber message appeared. Status page showed .46 quantity in left system and RF displayed. RSVR light on overhead panel was illuminated. We accomplished B757 QRH for Hydraulic Quantity for the left system. Nothing to do there; we began reviewing QRH for Hydraulic System Pressure (L ONLY) in the event that this would occur. Aircraft was dispatched under an MEL for the center electric right press indication. This probably had nothing to do with our problem; although we did think that at this time our problem was only an indicator problem; as all other parameters; including left system hydraulic pressure were normal. About 10 minutes later we received a call from the Number 2 Flight Attendant that numerous passengers were reporting fluid all over the right wing surface. This confirmed to us that we did indeed have a hydraulic leak. We declared an emergency with Center and turned around to ZZZ. We were about 250 miles west of ZZZ at this time with about 33;000 LBS of fuel. When we were headed back to ZZZ; Dispatch was informed via ACARS. Our previous review of QRH for system loss; confirmed that we would possibly be using alternate gear and flap extension if the normal and or PTU were ineffective. About 150 miles from ZZZ; the quantity had fallen to .21 system pressure was still good. I asked for a descent to FL180 in order to attempt to configure the aircraft for a normal landing before we lost all quantity and was down to depending on only the alternate methods. We were cleared to 16;000 FT. Slowed to about 235 KIAS and lowered the landing gear. It went down normally. Quantity and pressure remained as before. Slowed to 220 KIAS and lowered flaps 1. Normal operation; continued to slow as appropriate for flap speeds and attained flaps 20. We continued until about 100 miles from ZZZ and the quantity began falling; accompanied by an intermittent Hydraulic Engine Pump indication. While the light was out; we configured to flaps 25 for a normal landing. After this; the engine pump light came on steady and then the sys press caution light illuminated. Accomplished QRH for the pump and for the pressure; only item remaining was to turn off l electric hydraulic pump. As stated in the checklist; some spoilers would not work and roll rate might be reduced. We were flying with center autopilot engaged; and when the system failed; it was unable to control the roll axis. Autopilot was disconnected and it required 5 units left rudder trim and left aileron trim to maintain level flight. Nice to discover while still 25 minutes from landing. Flight Attendant coordination was accomplished and the passengers were informed and reassured that a normal landing would occur. Hand flew an ILS to ZZZ [and] landed as previously configured with flaps 25. Weight had been conveniently burned down to about 196;000 LBS. Rolled to the end; used differential braking to clear and had Maintenance meet us to pin the gear and tow in. Manual spoiler was planned and accomplished. Left reverser was inoperative. Turns out the number 2 spoiler actuator on the right wing; according to a preliminary report from maintenance after parking; had sprung a leak. Open for comments on decision to configure early. As far as my research indicates it did nothing to compound the problem. Fuel needed to be burned down anyway. Why wait to see if the backup methods would work? Always do in the SIM; but who knows when they were tested on the real thing?

Data retrieved from NASA's ASRS site 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.