EMB-170 flight crew reported receiving multiple advisory messages on descent; then experienced nose wheel steering failure after landing; necessitating a tow into the gate.
Synopsis
EMB-170 flight crew reported receiving multiple advisory messages on descent; then experienced nose wheel steering failure after landing; necessitating a tow into the gate.
Narrative
After initiating descent we had 2 advisory messages display. The first advisory was SPDA FAIL the second was FUEL FEED 2 FAULT. After complying with the QRH; No action was required except to monitor fuel system. Clearing the runway EICAS messages ENG 1 REV PROT FAULT; ENG 2 REV PROT FAULT; CRG FWD VENT FAIL; ENG 1 & 2 NO DISPATCH. We cleared Runway XXR and assessed the messages. On Taxiway 1 I called for flaps up and my First Officer (FO) started the APU. After turning on [Taxiway] 2 we were told that our gate was occupied. We pulled into the scenic pad to wait for our gate. After sitting there for a few minutes I called to shut down engine number 2. We received a call from operations that our gate had opened around XA:30. We were given a taxi clearance 1; 3; cross Runway XYR; right turn 4; hold short XYC. After a few minutes we were cleared to cross XYC. I released the parking brake and started to cross. My FO noted the EICAS message STEER OFF had appeared. Which I thought was odd because I was still steering with the tiller. I let up on the tiller and reengaged it with success. Half way across the runway we got a STEER FAIL message and I lost all steering with the tiller. I tried steering with the rudder before coming to a full stop on the runway. My FO alerted Tower we had lost all steering on XYC. We set the parking brake and alerted operations and Maintenance. After that we ran the STEER FAIL check list and reset it. It did not work and we could not control with differential braking. We got towed back to the gate XX.Cause: STEER Fail on an active runway was the cause. We are not aware of what caused the Steering to fail on the aircraft. I imagine that it had to do with some sort of electrical connection problem. We deduced that it was not a hydraulic problem because we did have braking action with the rudder pedals and the system looked normal on the hydraulic systems page. We had multiple EICAS messages after landing that were associated with the SPDA FAIL. The other messages that popped up didn't seem to make any sense in terms of that failures we had.Suggestions: I don't have much of a suggestion. What happened was a mechanical failure of our steering function that was unfortunately on a runway. We did everything that we could think of to fix the situation. Nothing worked for us so our best solution was to get a team to tow us off of the runway to the gate. If we had gotten the notification earlier we wouldn't have entered the runway but there was no indication that our steering was going to fail at that time or before while we were taxiing.
Second reporter narrative
During descent; we received SPDA FAIL and FUEL FEED 2 FAIL EICAS messages. We ran the appropriate checklists and continued the flight. After landing; we received the ENG 1 and 2 NO DISPATCH; CRG FWD VENT FAIL; ENG 1 and 2 REV PROT FAULT EICAS messages immediately after clearing the runway. We contacted maintenance and simultaneously received an instruction to wait in the scenic pad by the ground controller. While waiting for our gate to open; we shutdown engine 2 and continued to assess the messages. A few minutes later; ground instructed us to taxi via 2; 3; cross XZL; and hold short of XYC on 4. Shortly after; we were cleared to cross XYC on 4. While crossing the runway; we received the STEER FAIL EICAS message and the Captain was unable to steer the aircraft. We were put in a position where the safest answer was to stop and immediately contact Tower. We ran the STEER FAIL checklist and contacted Maintenance. We were unable to fix the problem and coordinated with operations to have a tug bring us to [gate] XX.Cause: We are unaware of what specifically caused the steering to fail; however I believe it was a result of some sort of electrical malfunction. The list of EICAS messages after landing was very confusing and did not seem to isolate one particular system.Suggestions: I do not currently have a suggestion that relates to a mechanical failure; but I believe these situations require crew members to slow down and use all applicable resources to make the safest decision.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.