A B757 captain reported losing his left main hydraulic system on an overwater flight. He coordinated...

Narrative:

One hour 40 minutes out of destination. The EICAS message and left engine hydraulic pump press light came on. We completed the irregular checklist and called dispatch and maintenance. We discussed the problem and continued. 10 minutes later the left hydraulic quantity began to decrease; so we completed the irregular checklist and again called dispatch and maintenance. We discussed this additional problem. I made the decision to divert. We declared an emergency with ATC and received clearance to land. I briefed the purser. Entering the pattern the flaps and landing gear were deployed using the alternate flap and gear extend irregular checklists. We then made an emergency landing; and after exiting the runway we shut down and were towed to the gate as nose wheel steering was inop. All irregular checklists were followed; and the outcome was a successful emergency landing.

Original NASA ASRS Text

Title: A B757 Captain reported losing his left main hydraulic system on an overwater flight. He coordinated with Dispatch and Maintenance; ran the procedure; declared an emergency; and diverted to the nearest suitable airport.

Narrative: One hour 40 minutes out of destination. The EICAS message and left engine hydraulic pump press light came on. We completed the irregular checklist and called Dispatch and Maintenance. We discussed the problem and continued. 10 minutes later the left hydraulic quantity began to decrease; so we completed the irregular checklist and again called Dispatch and Maintenance. We discussed this additional problem. I made the decision to divert. We declared an emergency with ATC and received clearance to land. I briefed the Purser. Entering the pattern the flaps and landing gear were deployed using the alternate flap and gear extend irregular checklists. We then made an emergency landing; and after exiting the runway we shut down and were towed to the gate as nose wheel steering was inop. All irregular checklists were followed; and the outcome was a successful emergency landing.

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.

Attributes
ACN	890381
Time
Date	201004
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Plan	IFR
Component
Aircraft Component	Hydraulic Main System
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 210 Flight Crew Total 25000 Flight Crew Type 10000
Events
Anomaly	Aircraft Equipment Problem Critical

A B757 captain reported losing his left main hydraulic system on an overwater flight. He coordinated with dispatch and maintenance; ran the procedure; declared an emergency; and diverted to the nearest suitable airport.