B777 first officer reported returning to departure airport following the loss of pressure and fluid ...

Narrative:

Shortly after takeoff; we received an alert for low pressure in the left hydraulic system; hydraulic pr left. A review of the system schematic indicated a complete loss of hydraulic fluid in that system. We delegated responsibilities and pulled up the corresponding applicable checklist. ATC was notified as the problem warranted a return to [departure airport]. The checklist was completed and we were instructed by ATC to hold at [an] intersection. Dispatch and [maintenance] were notified and agreed with our return decision as this was an ETOPS flight over extensive open ocean. We declared the need to dump fuel to ATC and requested a proper place to do so. We were cleared by ATC to dump fuel at 10;000 feet. We informed the flight attendants during the entire process. The passengers were kept informed as well. The diversion guide was followed and we dumped fuel so as to land below maximum landing weight. We evaluated landing performance data relative to our hydraulic problem and determined we were safe to land based on performance criteria and factors of the degraded condition. We also consulted dispatch and obtained landing data from them. We completed all applicable checklists and landed uneventfully and returned to the gate.

Original NASA ASRS Text

Title: B777 First Officer reported returning to departure airport following the loss of pressure and fluid in the left hydraulic system.

Narrative: Shortly after takeoff; we received an alert for low pressure in the left hydraulic system; HYD PR L. A review of the system schematic indicated a complete loss of hydraulic fluid in that system. We delegated responsibilities and pulled up the corresponding applicable checklist. ATC was notified as the problem warranted a return to [departure airport]. The checklist was completed and we were instructed by ATC to hold at [an] intersection. Dispatch and [Maintenance] were notified and agreed with our return decision as this was an ETOPS flight over extensive open ocean. We declared the need to dump fuel to ATC and requested a proper place to do so. We were cleared by ATC to dump fuel at 10;000 feet. We informed the flight attendants during the entire process. The passengers were kept informed as well. The diversion guide was followed and we dumped fuel so as to land below maximum landing weight. We evaluated landing performance data relative to our hydraulic problem and determined we were safe to land based on performance criteria and factors of the degraded condition. We also consulted Dispatch and obtained landing data from them. We completed all applicable checklists and landed uneventfully and returned to the gate.

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.

Attributes
ACN	1599079
Time
Date	201812
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Tower
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B777-200
Operating Under FAR Part	Part 121
Flight Phase	Climb
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine Flight Crew Instrument
Experience	Flight Crew Last 90 Days 200.3 Flight Crew Total 11828.83 Flight Crew Type 1479.38
Events
Anomaly	Aircraft Equipment Problem Less Severe Inflight Event / Encounter Fuel Issue

B777 first officer reported returning to departure airport following the loss of pressure and fluid in the left hydraulic system.