B777-200
Aircraft Equipment Problem Critical
Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport; General Declared Emergency
Aircraft
Just after passing ZZZ the EICAS message 'HYD QTY LOW R' came on and we checked the hydraulic quantity and the right hydraulic quantity was '0'. Just as we were checking the quantity the EICAS message 'HYD PRESS PRI R' came on. We ran and completed the QRH checklist for both EICAS messages. At approximately 100-150 miles east of ZZZ we declared an emergency with ATC and requested a turn back direct to [our departure airport]. We dumped approximately 50;000 LBS of fuel starting approximately 100 miles east of ZZZ at FL320 starting at approximately XA20Z. We executed an overweight landing at [our departure airport] at approximately 519;000 LBS with a sink rate of approximately 100 FPM and the landing was normal.
A B777-200 flight crew declared an emergency and returned to their departure airport after suffering the loss of fluid and pressure to the right hydraulic system.