Narrative:

While at cruise altitude we were alerted to the EICAS screen message C hydraulic qty. Opening the lower EICAS screen we noted the center hydraulic fluid level approximately .72 and declining. As the pilot monitoring I opened the QRH and performed the C hydraulic qty checklist. The fluid level continued to drop. Now; C hydraulic system press was shown on the EICAS and I performed that checklist as well. There was still .07 remaining on the center hydraulic system quantity indicator. I called for a phone patch to query maintenance control. This aircraft had suffered a center hydraulic system failure just four days earlier and I wanted to ascertain the fluid level remaining in that event and whether nose wheel steering was available to that crew. After a thorough briefing of the approach and what we could reasonably expect upon landing we declared an emergency with ZZZ center. Due to the remote chance of not having nose wheel steering we wanted give ATC as much heads up time to allow for other aircraft they could potentially sequence behind us to be rerouted to another runway. We alerted station operations as to our status and the possible need for a tow off the runway. With the many possibilities discussed and the many ahead of us we began to run out of time. Through the course of this event I had sent more than one ACARS message to flight control and at this time I am not positive I advised them of our emergency status. At top of descent I assumed the role of pilot flying. The arrival and landing were uneventful and we had full authority of nose wheel steering. We decided to use a tug to make the final turn into the parking spot to preclude the chance of losing nose wheel steering at perhaps the most inopportune time.

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Original NASA ASRS Text

Title: A B767-300 flight crew dealt successfully with a Center Hydraulic system failure and landed without incident at their destination.

Narrative: While at cruise altitude we were alerted to the EICAS screen message C HYD QTY. Opening the lower EICAS screen we noted the center hydraulic fluid level approximately .72 and declining. As the Pilot Monitoring I opened the QRH and performed the C HYD QTY checklist. The fluid level continued to drop. Now; C HYD SYS PRESS was shown on the EICAS and I performed that checklist as well. There was still .07 remaining on the center hydraulic system quantity indicator. I called for a phone patch to query Maintenance Control. This aircraft had suffered a center hydraulic system failure just four days earlier and I wanted to ascertain the fluid level remaining in that event and whether nose wheel steering was available to that crew. After a thorough briefing of the approach and what we could reasonably expect upon landing we declared an emergency with ZZZ Center. Due to the remote chance of not having nose wheel steering we wanted give ATC as much heads up time to allow for other aircraft they could potentially sequence behind us to be rerouted to another runway. We alerted station operations as to our status and the possible need for a tow off the runway. With the many possibilities discussed and the many ahead of us we began to run out of time. Through the course of this event I had sent more than one ACARS message to Flight Control and at this time I am not positive I advised them of our emergency status. At top of descent I assumed the role of Pilot Flying. The arrival and landing were uneventful and we had full authority of nose wheel steering. We decided to use a tug to make the final turn into the parking spot to preclude the chance of losing nose wheel steering at perhaps the most inopportune time.

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.