Narrative:

Climbing out from departure airport at 21;000 ft I noticed that the we had a red FMS indication and FD indication on the pfd. All associated information was missing including FD modes and the FD command bars; but the autopilot was maintaining attitude; so there was no noticeable bump or cavalry horn when FMS went off-line. We had just been given direct from center so we tuned the VOR and started green needle navigation. I turned controls over to the copilot and picked up the QRH; but couldn't find loss of FMS in either the messages or non messages section. Then I noticed that we lost the navigation 1 radio. At that point I didn't know why I had multiple failures; and seriously degraded navigation. I seriously hoped that I didn't have a fire in the electronics area. I took the controls back and made the decision to divert. Departure airport is not an option for diverting and ZZZ1 was closer with longer runways. I informed ATC of our condition; sob; fob and our intention to divert. I had no FMS and ATC informed me that we were about 60 NM from the field. I asked the copilot to inform dispatch; ZZZ1 operation and the flight attendant. As we approached ZZZ1 I noticed navigation 1 back online. I also decided to land overweight to get the passengers safely on the ground as quickly as possible. We rolled the trucks in ZZZ1 and made an uneventful landing. It took them about a 1/2 hour to get us ready to continue. On the ground the FMS was failed. The mechanics said they believed that as the FMS shut down it temporarily knocked navigation 1 off-line but it op checked good. It would be nice to have something in the QRH about FMS failures.

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Original NASA ASRS Text

Title: CRJ200 Captain discovers the FMC has failed climbing through FL210 and begins using green needle navigation. No QRH guidance can be found. NAV 1 then apparently failed; and the Captain elects to divert to the nearest suitable airport.

Narrative: Climbing out from departure airport at 21;000 FT I noticed that the we had a red FMS indication and FD indication on the PFD. All associated information was missing including FD modes and the FD command bars; but the autopilot was maintaining attitude; so there was no noticeable bump or cavalry horn when FMS went off-line. We had just been given direct from Center so we tuned the VOR and started green needle NAV. I turned controls over to the copilot and picked up the QRH; but couldn't find loss of FMS in either the messages or non messages section. Then I noticed that we lost the NAV 1 radio. At that point I didn't know why I had multiple failures; and seriously degraded navigation. I seriously hoped that I didn't have a fire in the electronics area. I took the controls back and made the decision to divert. Departure airport is not an option for diverting and ZZZ1 was closer with longer runways. I informed ATC of our condition; SOB; FOB and our intention to divert. I had no FMS and ATC informed me that we were about 60 NM from the field. I asked the copilot to inform Dispatch; ZZZ1 operation and the Flight Attendant. As we approached ZZZ1 I noticed NAV 1 back online. I also decided to land overweight to get the passengers safely on the ground as quickly as possible. We rolled the trucks in ZZZ1 and made an uneventful landing. It took them about a 1/2 hour to get us ready to continue. On the ground the FMS was failed. The mechanics said they believed that as the FMS shut down it temporarily knocked NAV 1 off-line but it op checked good. It would be nice to have something in the QRH about FMS failures.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.