A220 crew reported a DMC 2 failure followed thereafter by other system failures and communication problem during cruise. Crew returned to departure airport after executing appropriate checklists and landed safely.
Synopsis
A220 crew reported a DMC 2 failure followed thereafter by other system failures and communication problem during cruise. Crew returned to departure airport after executing appropriate checklists and landed safely.
Narrative
Just prior to leveling off at FL340 we encountered a significant number of system failures. It began with a DMC (Display Management Computer) 2 FAULT that quickly turned into a DMC 2 FAIL; and then other systems as well to include HYD 3 LO PRESS; R PACK FAIL; IPC (Intermediate Pressure Checkvalve) 2 FAIL; along with 3 EICAS pages full of other FAULTS. We were also down to a single radio and single FMS. As we were being inundated with messages we felt a change in cabin pressurization and noticed the cabin beginning to climb. Due to this (and the significant failures we were able to quickly ascertain); we assigned PF and PM roles; requested a descent; [requested priority handling]; and notified our intention to return to ZZZ. Initially I remained PF; while Person A began to execute the ECL's (Electronic Checklist) in priority order. Once completed; and the aircraft was in a stable/controllable condition we began to assess the totality of the situation realizing we had 2 issues that would/may affect landing performance. After running the HYD 3 LOW PRESS ECL we knew we lost the system (50 PSI; no green lines); and would have an OLD (Operational Landing Distance) of 1.15. Additionally we discussed the potential of a SLAT and/or FLAP failure (SLAT SLOW and FLAP FAULT msgs shown) and the additional performance penalties we may incur. At this point we switched PF and PM roles. I contacted the FAs (Flight Attendants) explaining our situation; intent to return to ZZZ. I then addressed the customers stating that we were experiencing a malfunction of certain systems to include a hydraulic system and that a return to ZZZ was necessary. I reiterated that we had redundant systems and that the aircraft was in full control. At this point we were approaching ZZZ and requested a 15nm final for early configuration of the aircraft. As we moved the flap lever to position 1 we received a SLAT FAIL caution as we anticipated. We broke off the approach; requested box patterns from ATC; and ran the ECL. Unable to recover the slats; facing an additional OLD of 1.40; and considering the potential for a flap failure as well I decided to reach out to Dispatch; and Mx (Maintenance) Control (while requesting the Chief Pilot be brought in as well). Because our SATCOM was deferred and we only had 1 radio I elected to step outside company policy and use my cellphone. In discussing the situation we wanted clarity as to whether it would be ok to select a further flap setting in an attempt to extend the flaps. Mx control said they were uncertain; but upon further review of the ECL we noted in the Deferred for Landing" portion it stated to select Flaps 4. Confident that we could now select this; and that if doing so was successful we would have the performance necessary for landing XXL. I spoke to the FAs conveying this information and stated we would begin the approach if successful. Fortunately the flaps extended normally and we made an uneventful landing. Upon landing we verified we had nose wheel steering (as we had a NOSE STEER FAULT); and advised ATC we would taxi to the gate under our own power. The flight was met by personnel; a ZZZ Asst. Chief Pilot; and Mx personnel. All customers deplaned and were put on a different aircraft to continue to ZZZ1. We had a discussion with Person B about the nature of things. He added that Mx was questioning our decision to return; which both Person A and I agreed was never a decision. I have to believe this was only because they did not have a full picture of the problem. We removed ourselves from the flight due to the fatiguing nature of the event and went home."
Second reporter narrative
[Report narrative contained no additional information]
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.