Narrative:

Oe (operational experience) instructor pm (pilot monitoring) in level in cruise at FL370. Student was PF (pilot flying). Noticed center hydraulic system qty light come on overhead and associated EICAS. (Approximately 250 nm north of ZZZ). Checked EICAS and saw center hydraulic fluid at .47 and dropping very slowly. Notified [operations] and ATC of possible center hydraulic system failure and divert. Hydraulic fluid qty slowly reduced but we didn't have system failure (center hydraulic sys press light) until within 20nm of ZZZ. We [advised ATC] and asked for delaying vectors while we worked the issue and checklist. While doing the center hydraulic sys pressure checklist and configuring the flaps; we also got a trailing edge flap disagree msg on EICAS. After going through that checklist I attempted to get a hold of an [engineer] in ZZZ1 just to confirm the proper flap procedure that the checklist was telling us to do. It took a very long time to get a [engineer]. He tried but wasn't really helpful and I don't think he was a [engineer]. We continued the checklist and proceeded to land at that point because fuel was starting to become an issue. We landed with flaps 1 (ILS xxr ZZZ) and ended up having nose wheel steering. We cleared the runway. Taxi to ramp was uneventful. Maintenance met us on ramp and said that we did indeed have a leak. Center hydraulic fluid on EICAS read .10 at engine shutdown. The [event] was complicated by the fact that we had a flap issue while working the hydraulic failure. I was sorely disappointed that it took at least 15 minutes or more to get a hold of what I thought was going to be a [engineer] and didn't get one. I wanted to be 100% certain that our actions were correct and I wanted [an engineer] to back us up on that. Never happened. Thankfully I had a very sharp student and jump seater as well that provided a lot of guidance and support so that we operated and landed safely without incident.

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Original NASA ASRS Text

Title: B767 flight crew reported multiple problems with the aircraft hydraulic system; and being unable to reach a company engineer for support.

Narrative: OE (Operational Experience) Instructor PM (Pilot Monitoring) in level in cruise at FL370. Student was PF (Pilot Flying). Noticed Center Hydraulic System QTY light come on overhead and associated EICAS. (Approximately 250 nm North of ZZZ). Checked EICAS and saw CTR HYD fluid at .47 and dropping very slowly. Notified [Operations] and ATC of possible CTR HYD system failure and divert. Hydraulic fluid QTY slowly reduced but we didn't have system failure (CTR HYD Sys Press light) until within 20nm of ZZZ. We [advised ATC] and asked for delaying vectors while we worked the issue and checklist. While doing the Center HYD Sys pressure checklist and configuring the flaps; we also got a Trailing Edge Flap disagree msg on EICAS. After going through that checklist I attempted to get a hold of an [Engineer] in ZZZ1 just to confirm the proper flap procedure that the checklist was telling us to do. It took a VERY long time to get a [Engineer]. He tried but wasn't really helpful and I don't think he was a [Engineer]. We continued the checklist and proceeded to land at that point because fuel was starting to become an issue. We landed with Flaps 1 (ILS XXR ZZZ) and ended up having nose wheel steering. We cleared the runway. Taxi to ramp was uneventful. Maintenance met us on ramp and said that we did indeed have a leak. Center HYD Fluid on EICAS read .10 at engine shutdown. The [event] was complicated by the fact that we had a flap issue while working the Hydraulic failure. I was sorely disappointed that it took at least 15 minutes or more to get a hold of what I thought was going to be a [Engineer] and didn't get one. I wanted to be 100% certain that our actions were correct and I wanted [an Engineer] to back us up on that. Never happened. Thankfully I had a very sharp student and jump seater as well that provided a lot of guidance and support so that we operated and landed safely without incident.

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.