Narrative:

About half way to destination during cruise the left hydraulic pump pressure light illuminated. As we started the irregular procedure checklist the light flickered and went out and the associated EICAS message canceled. We checked the hydraulic quantity and found that it was above 1.12 gallons. Approximately 30 minutes later the left hydraulic pump pressure light came on again and remained on and we ran the irregular procedure for a left hydraulic pressure light illuminated. We shut the engine driven pump off and looked at the other hydraulic procedure problems. A code was sent to maintenance for notification. Just prior to the top of decent in cruise we now had a left rsvr/left system press light illuminated which we expected might happen. The first officer checked the quantity and it was about .03 gallons and he gave me the control of the aircraft and started the irregular procedures for hydraulic system pressure left and rudder ratio. We agreed that because we were at cruise the left pump system was not needed and that if there were a leak turning off the electric pump may leave enough fluid in the system for the electric pump or the pto when the time came for its use. The flight remained normal through the descent briefing and checklist until air traffic requested a speed of 210 KTS at 13;000 ft heading 260 degree. I turned on the electric hydraulic pump when I asked for flaps 1 and we then received multiple system EICAS messages as described in the checklist which the first officer began working (le slat disagree; power xfr unit). I handled the radios and the pilot flying duties and asked air traffic control for delay vectors that we were having hydraulic situations that required these delaying vectors. We were placed in a box pattern 30 miles on final approach and decided that because of the multiple system problems that an announcement to air traffic control was warranted. I declared an emergency with 190 souls on board and 1 hour 45 minutes remaining fuel. I sent a message to dispatch to call me and rang the purser and said this was a cabin advisory; that she could expect a normal approach to landing; and that the touchdown speed will be higher than normal and that we will stop on the runway and be required to be towed to the gate because we would not have ground steering. She would have about fifteen minutes before touchdown and asked was there anything else she needed and was this enough time for her to get everything done? Another ACARS to dispatch to call me and I received two frequencies which neither worked; so I called air traffic control to notify my dispatcher of the nature of our emergency and requested approach clearance. A visual approach to a full stop on the runway was conducted and was uneventful. We came to a stop where we held the brakes and shut down the engines. The fireman set nosewheel chocks and I made an announcement to the passengers to remain in their seats and also included a quick explanation of the landing and why I was unable to taxi to the gate. The airport fire department was very professional and knowledgeable of our aircraft and performed a visual inspection; chocked the aircraft and placed fans on our main gear brakes to cool them down. Thanks to my first officer for all that he did; his aircraft knowledge; crew resource management; advocating his ideas from the beginning; through the touchdown; engine shutdown and until arriving at the gate. He was nothing less than outstanding. Hindsight: I would want to have contacted dispatch before I had descended below their coverage for their input. Maybe then local maintenance would have been notified and arrived to inspect the aircraft and place the gear pins before towing was initiated. Sending ramp personal to tow an emergency aircraft is totally unacceptable and could have resulted in aircraft damage or worse; passengers injured. Also because of maintenance not being notified this took 40 minutes before the towing was started and 52minutes to arrive at our gate.

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Original NASA ASRS Text

Title: A B757 crew described the loss of the left hydraulic system fluid during flight. An emergency was declared followed by an emergency landing.

Narrative: About half way to destination during cruise the left hydraulic pump pressure light illuminated. As we started the Irregular Procedure checklist the light flickered and went out and the associated EICAS message canceled. We checked the hydraulic quantity and found that it was above 1.12 gallons. Approximately 30 minutes later the left hydraulic pump pressure light came on again and remained on and we ran the Irregular Procedure for a left hydraulic pressure light illuminated. We shut the engine driven pump off and looked at the other hydraulic procedure problems. A code was sent to maintenance for notification. Just prior to the top of decent in cruise we now had a Left RSVR/Left SYS PRESS light illuminated which we expected might happen. The First Officer checked the quantity and it was about .03 gallons and he gave me the control of the aircraft and started the irregular procedures for hydraulic system pressure L and rudder ratio. We agreed that because we were at cruise the left pump system was not needed and that if there were a leak turning off the electric pump may leave enough fluid in the system for the electric pump or the PTO when the time came for its use. The flight remained normal through the Descent Briefing and Checklist until Air Traffic requested a speed of 210 KTS at 13;000 FT heading 260 degree. I turned on the electric hydraulic pump when I asked for Flaps 1 and we then received multiple system EICAS Messages as described in the checklist which the First Officer began working (LE Slat Disagree; Power XFR Unit). I handled the radios and the pilot flying duties and asked Air Traffic Control for delay vectors that we were having Hydraulic situations that required these delaying vectors. We were placed in a box pattern 30 miles on final approach and decided that because of the multiple system problems that an announcement to Air Traffic Control was warranted. I Declared an Emergency with 190 souls on board and 1 hour 45 minutes remaining fuel. I sent a message to Dispatch to call me and rang the Purser and said this was a Cabin Advisory; that she could expect a normal approach to landing; and that the touchdown speed will be higher than normal and that we will stop on the runway and be required to be towed to the gate because we would not have ground steering. She would have about fifteen minutes before touchdown and asked was there anything else she needed and was this enough time for her to get everything done? Another ACARS to Dispatch to call me and I received two frequencies which neither worked; so I called Air Traffic Control to notify my Dispatcher of the nature of our Emergency and requested approach clearance. A Visual Approach to a full stop on the runway was conducted and was uneventful. We came to a stop where we held the brakes and shut down the engines. The Fireman set nosewheel chocks and I made an announcement to the passengers to remain in their seats and also included a quick explanation of the landing and why I was unable to taxi to the gate. The Airport Fire Department was very professional and knowledgeable of our aircraft and performed a visual inspection; chocked the aircraft and placed fans on our main gear brakes to cool them down. Thanks to my First Officer for all that he did; his aircraft knowledge; crew resource management; advocating his ideas from the beginning; through the touchdown; engine shutdown and until arriving at the gate. He was nothing less than outstanding. Hindsight: I would want to have contacted Dispatch before I had descended below their coverage for their input. Maybe then local Maintenance would have been notified and arrived to inspect the aircraft and place the gear pins before towing was initiated. Sending ramp personal to tow an emergency aircraft is totally unacceptable and could have resulted in aircraft damage or worse; passengers injured. Also because of Maintenance not being notified this took 40 minutes before the towing was started and 52minutes to arrive at our 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.