A B757 EICAS alerted lt hydraulic system press so the crew completed the QRH first securing the engi...

Narrative:

At cruise flight received EICAS warning of left engine hydraulic pressure. Procedure called for selecting left engine hydraulic pump off. Abnormal checklist completed; preceded on course to destination. Several hours into the flight; it became aware that left system hydraulic fluid was leaking down from normal; past RF limit of .75 and further. Talking to dispatch with relay to maintenance control; captain decided to turn off left hydraulic system electric pump also which slowed the reduction in quantity level. Approaching our destination in descent; system further reduced to .30 limit quantity and remained constant until gear down selection for approach and landing. Gear extension was delayed/not normal extension time; quantity reduced further past the .30 level; ptu engaged notice on EICAS. Flap extension was very slow and crew elected to land with 20 flaps in case a go around was necessary. Declared emergency with ATC; requested ground equipment be sent out; requested the opening of longest runway which was closed as per ATIS at the early hour time. Normal cabin crew and passenger PA notifications completed; landed normally; soft touchdown just past halfway down runway. Notified ground equipment that their further assistance was not required and taxied to gate.

Original NASA ASRS Text

Title: A B757 EICAS alerted LT HYD SYS PRESS so the crew completed the QRH first securing the engine driven pump; then as the fluid loss continued; secured the left electric hydraulic pump to slow fluid loss conserving it for the emergency landing.

Narrative: At cruise flight received EICAS warning of Left Engine Hydraulic Pressure. Procedure called for selecting Left Engine Hydraulic pump off. Abnormal checklist completed; preceded on course to destination. Several hours into the flight; it became aware that left system hydraulic fluid was leaking down from normal; past RF limit of .75 and further. Talking to Dispatch with relay to Maintenance Control; Captain decided to turn off left hydraulic system electric pump also which slowed the reduction in quantity level. Approaching our destination in descent; system further reduced to .30 limit quantity and remained constant until gear down selection for approach and landing. Gear extension was delayed/not normal extension time; quantity reduced further past the .30 level; PTU engaged notice on EICAS. Flap extension was very slow and crew elected to land with 20 flaps in case a go around was necessary. Declared emergency with ATC; requested ground equipment be sent out; requested the opening of longest runway which was closed as per ATIS at the early hour time. Normal cabin crew and passenger PA notifications completed; landed normally; soft touchdown just past halfway down runway. Notified ground equipment that their further assistance was not required and taxied to gate.

Data retrieved from NASA's ASRS site as of July 2013 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.

Attributes
ACN	1056134
Time
Date	201212
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Light	Night
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Hydraulic System
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical

A B757 EICAS alerted lt hydraulic system press so the crew completed the QRH first securing the engine driven pump; then as the fluid loss continued; secured the left electric hydraulic pump to slow fluid loss conserving it for the emergency landing.