Date: 201810
Local time of day: 0601-1200
Location: IAH.Airport, TX
Light: Daylight
Aircraft: Regional Jet 900 (CRJ900)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
ATC / advisory: Ground IAH
Aircraft component: FMS/FMC
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Workload; Distraction; Situational Awareness
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Aircraft In Service At Gate
Result: Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: MEL; Aircraft; Human Factors
Primary problem: MEL

Narrative: We boarded the aircraft in Houston and were planned for a flight to ZZZ1. We noticed on the release that both FMS units were deferred so the flight plan had us essentially going from VOR to VOR. We did our due diligence and looked up the MEL and read thru the procedures. One of the procedures was to check and verify the waypoints and route. The First Officer (FO) was uncomfortable with how we could accomplish these tasks. I said I thought there were a couple different ways to do it; but he wasn't satisfied and said he was going to call dispatch. I really didn't think that was necessary but in trying to keep a happy cockpit; I didn't say anything and he proceeded to call and talk to dispatch. Initially they didn't have an answer to satisfy him; but eventually we agreed that the magnetic course on the flight plan was enough to satisfy the requirement. ATC wanted us to do a SID even though our flight plan from Dispatch was done without a SID. Clearance finally said that was fine and we were on our way. Throughout the flight; the FO seemed uncomfortable with the situation; then when coming into ZZZ1; ATC wanted us to do a STAR. I was the non-flying pilot and was running the radios. I told them we were non RNAV equipped; and couldn't accept a STAR. We were asked multiple times to accept different STARS and I said that we couldn't verify one or two of the waypoints that weren't triangulated along the route. ATC was frustrated; but I told them we would gladly fly the route on the STAR but that didn't seem to satisfy them. With all the concerns that the FO was having; I was trying to stick up for his somewhat correct point of view that we were going to be on a STAR that we couldn't legally accept with the MEL. I believe that is why Dispatch did not have a STAR on our flight plan. ATC eventually vectored us to ZZZ1. Once at the gate; the FO wanted to call Maintenance to see if they would clear the MEL since FMS's appeared to work properly. I said that was a good idea. The FO left the cockpit; a maintenance guy came and eventually did put both FMS units back in service. I was given a call by scheduling; and they said I would be getting a reserve FO because my FO was uncomfortable taking the plane in its current condition. I told scheduling that Maintenance cleared the issue; then I thought my original FO was going to come back. But according to my original FO; he said he would have come back to continue flying but the change of FO's was already done. The cause of the problem was with the FMS units being deferred; my FO was possibly a little too conservative in interpreting the pilot duties from the MEL book. The issue was resolved but I don't think he was ever completely comfortable with the situation. Maybe the MEL could have a better description of how the pilots are to verify the waypoints and routes. I think that would help to calm the nerves of some flight crew looking for better clarification.




Synopsis: CRJ-900 Captain reported the First Officer was very uncomfortable flying the aircraft with both FMS's on MEL. The Captain would like to see a better description in the MEL regarding how to operate in this situation.