DC-10 Undifferentiated or Other Model
Aircraft Equipment Problem Critical; Deviation - Altitude Excursion From Assigned Altitude
Air Traffic Control Provided Assistance; Flight Crew Landed As Precaution; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Regained Aircraft Control; Flight Crew Landed in Emergency Condition; General Declared Emergency
Aircraft
At FL380 we received a Level 1 alert of HYD 3 OFF. Hydraulic pressure was at 0 on System 3 with both pumps failed. The autopilot automatically disconnected and the aircraft pitched up with approximately a 700 foot gain prior to the Captain regaining altitude control. We referenced the level 1 checklist and continued toward destination. We asked for vectors and a slow descent to the landing runway; and left turn-off ability. During the descent the autopilot didn't want to stay engaged; forcing the Captain to hand fly much of the arrival. We also consulted total HYD system 3 FAIL checklist to prepare for that possibility. Upon extended vectors we began to configure and received a SLAT DISAG so we slowed down and re attempted with success (the NRMP powered HYD System 3 to full pressure as we anticipated.) We subsequently configured to 15 flaps (all of this occurred around 210 KIAS.) We then lowered the landing gear to verify that it would extend prior to commencing the approach. Both main gears lowered but the nose failed to lower and HYD 3 system pressure again went to 0 with both pumps failed. We entered holding and ran the checklist for HYD 3 system fail. We took advantage of an MD-11 F/O who was jumpseating to assist us in running checklists. We performed an alternate gear extension and the nose gear lowered and locked into place. As we continued the approach; we received HYD System 2 high temp alerts with first the left pump then the right pump overtemping and shutting off with associated alerts. Max temperature that I saw was 110C. We finished the configuration to 35 flaps and completed the approach and landing. Upon landing; both HYD system 2 and 3 came back to full pressure. We exited the runway and were inspected by the fire department who reported no leaks. We taxied to spot 15 but when we tried to turn into the gate (with all 3 systems indicating normal) the aircraft was slow to respond. The Captain stopped and we were towed the rest of the way into the gate.
An MD-10 aircraft suffered a Hydraulic System Number 3 failure and subsequent autopilots disconnect; resulting in a 700 feet altitude deviation before the Captain regained control. The autopilot would not stay engaged; requiring the Captain to hand-fly the airplane. A slat disagree indication was overcome; [and] then the nose wheel failed to extend normally and was extended with the alternate system. The next challenge was Hydraulic System Number 2 High Temp indications followed by both pumps shutting down. After landing both hydraulic systems Number 2 and Number 3 returned to full pressure; but during taxi-in the aircraft was reported as slow to respond.