Date: 202104
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: B767-300 and 300 ER
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Cargo / Freight / Delivery
Flight phase: Initial Approach
Airspace: Class D ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Hydraulic Main System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Communication Breakdown; Situational Awareness; Troubleshooting
Second reporter function: Pilot Flying; First Officer
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Unstabilized Approach
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Aircraft; Human Factors; Procedure
Primary problem: Procedure

Narrative: I was the PM (Pilot Monitoring) for the flight and first approach. It started with a C HYD QTY (Center Hydraulic Quantity) EICAS in the terminal area of ZZZ. The QRH was completed. A RNAV GPS approach was conducted with the autopilot and autothrottles off. Weather was day/VMC. Immediately after gear and flaps were extended there was a complete failure of the C hydraulic system with the associated EICAS messages. I announced to the PF (Pilot Flying) that we would have to abandon the approach and complete the QRH. I coordinated a go around with Tower. I explained our problem and our need to perform the QRH before another attempt to land. While talking to Tower; I failed to monitor our airspeed after the First Officer (FO) arrested the rate of descent. I had not given him any guidance as to maintaining a particular speed or altitude. The stick shaker got my attention. I called 'Speed' just as the PF added power and recovered quickly.Tower handed us over to Approach. I explained the need to perform the QRH; the time needed to complete the QRH; and that we would only have 2 of three hydraulic systems. A few minutes into working on the QRH procedure ATC advised us that they were [giving priority to] us. ATC asked for souls on board and fuel state. The QRH was completed. I elected to become the PF for the landing. The landing and rollout were successful. Emergency vehicles escorted us to parking.Of course I wish I could do it over. I'm not happy with my initial performance with the problem. The system failure happened at the most inconvenient time. Nonetheless the decision to not land and fix the problem was easy enough. However; my initial execution was poor.  After announcing the problem to the PF; I should have simply called Go Around. That would've put us back into the 'Aviate' phase and eliminated the stick shaker activation. Then I would've told Tower of the Go Around. Everything else would have sequenced properly for the remainder of the flight.


Second narrative: The Captain was PM and I; the First Officer was PF for our flight. Takeoff; climb and cruise were uneventful and no issues or indications were observed until descent into ZZZ. After obtaining the latest weather at ZZZ we decided Runway XX would be the most suitable based on the winds (270/3) and we would plan on and request the RNAV XX into ZZZ. We loaded the approach; requested landing performance via ACARS and briefed it as a normal flight.Descending into the area required the use of the speed brakes in order to keep the aircraft on the established VNAV path as well as slow down to 240 kts when passing 10;000 ft. Once reaching 9000 ft on a downwind position we first saw the C HYD QTY EICAS message appear. The PM checked the status page and noticed a magenta 'RF' and an indication of 0.45 for the center hydraulic quantity. The PM ran the C HYD QTY QRH and the only information listed was 'the hydraulic quantity is low'. We completed the checklist; called for recall review; cancelled it and discussed that we would write it up once on the ground in ZZZ and advise maintenance of the issue. We continued our descent for the RNAV XX approach; reducing speed and configuring for the landing. We were issued a heading and to maintain 3000 till established and we were cleared for the approach. I had setup for an approach as briefed; set 1200 in the altitude window and the aircraft began a shallow descent in VNAV PATH down to the minimums. After calling for 'gear down; flaps 20';  I set 160 kts in the speed window and the C HYD SYS PRESS EICAS message appeared. I called for 'flaps 25; landing checklist' when the PM alerted me of the EICAS message. After this a series of additional EICAS messages appeared and discrete lights illuminated. I noticed LEADING EDGE; TRAILING EDGE; and TE FLAP ASYM as the associated discrete lights had illuminated as well and got my attention. As the list of messages and indications appeared; the PM stated 'We can't land like this; we're going to need to find a place to go figure out what's happened'.As the PF; I had set 146 as the target speed for the approach and had just disengaged the autopilot and authrottle as briefed on the arrival briefing for automation intent. After the PM made that statement I hesitated to continue descending as I knew we could not land in this condition. The PM advised tower that we had an issue and would need to stay in the traffic pattern in order to troubleshoot the problem and would not be able to land at this time. At this moment I noticed the low speed awareness tape had not continued trending downward and minimum operating speed (red and black tape) was now very close to our current speed. Shortly after the stick shaker came on for roughly one second as the airspeed trended into the minimum operating airspeed range. I immediately added thrust and added forward pressure on the control column to increase airspeed and stop the stick shaker. The PM called out 'Airspeed' as I was taking corrective action. ZZZ tower informed us we could climb to 3000 ft. to abandon our approach and to run the necessary QRH. The PM set 3000 in the altitude window; we both verified it and I pressed the GA (Go Around) switch on the thrust levers. We conducted the GA profile; when bringing the flaps to 20 I could feel the asymmetric condition as the aircraft pitched up and the thrust increased. Continuing with the GA the PM raised the landing gear up; we maintained runway heading and set a speed of roughly 185 kts in the climb out. During the climb out the master caution light was intermittent as the gear doors and landing gear indications were intermittent as well. I remained PF with the autopilot disengaged and the auto throttle engaged. The PM attempted to engage Right Autopilot Command but we noticed this did not initially work so I continued flying manually with no autopilot. ZZZ approach advised us to proceed direct to the ZZZ1 VOR and stay within 10 DME while we ran the QRH and advised them of our intentions. At this time ATC asked for souls on board and fuel remaining and we advised them we had 2 souls on board and roughly 2 hours of fuel. The PM ran through the C HYD SYS PRESS QRH; noticing the center hydraulic quantity was down to 0.15 at one point. With no success completing the QRH; we completed the descent and approach checklist from the deferred items followed by the alternate flap extension and alternate gear extension checklists. The leading and trailing edge flaps successfully extended to 20 and the landing gear was down and 3 green lights were illuminated. At this time the PF and PM switched roles as the captain stated he felt more comfortable conducting the approach to landing. The captain stated the briefing remained the same and talked about the different Vref as a result of the new flap setting. After a positive transfer of controls; I advised ZZZ approach we would like to return to ZZZ and conduct the RNAV XX approach. We were vectored on a left downwind for the approach at which time the PF reduced speed to the target speed of 156 based on a flaps 20 Vref of 151; while I completed the landing checklist from the deferred items. We advised ATC we would be able to land the aircraft normally; they informed us that ARFF (Aircraft Rescue & Fire Fighting) would be standing by the runway just in case. We landed Runway XX and exited at taxiway 1 and told tower we could taxi to the international cargo ramp without any additional assistance. We left the flaps down at 20 after landing in order to prevent any further issued with the flight control movement. After blocking in on the ramp; maintenance came up and informed us that a substantial amount of hydraulic fluid had leaked onto the right main gear. We completed the necessary post flight paperwork; placed it in the trip envelope and then conducted a post flight inspection speaking to ARFF and maintenance about the exterior of the aircraft. At this time the captain and I grabbed our flight bags and headed to the Company transport to leave the airport.Looking back on the event I think there were a few things that could've been done differently. The initial indication of the C HYD QTY should have been a sign that something may have gone wrong; and after running the associated QRH we could've perhaps asked to slow and configure early to identify if there was an issue while at a higher altitude rather than on final approach. My role of PF on final approach. Despite the indications; discrete lights and overall confusion that was occurring at the time I should've had focused solely on flying the airplane and not getting distracted by the other things going on. This may have prevented the stick shaker event from occurring. There was no clear command to go around once we encountered the C HYD SYS PRESS EICAS message. Rather than wait for instructions or what the Captain was trying to diagnose; I should've called go around instead of remaining at 2500 ft with the airspeed trending downward in that configuration. As the other crew member I could have voiced my opinions in a more assertive way; stating what I believe may have happened as well as consulting the Captain if he felt we should identify as an emergency at the time.


Synopsis: Flight crew reported having a stick shaker activation during a go around; which was attributed to a hydraulic system failure.