Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Procedure; Aircraft
Aircraft was serviced by Maintenance before the flight and several electrical resets were performed. During preflight; First Officer noticed the position was in error; and reset it. No other anomalies were detected. After takeoff; we noticed that the FMS seemed to have jumped and gave us a fairly straight out turn.  But we noticed it didn't seem correct based on the RNAV departure.  ATC queried us and at the same time we noticed the discrepancy and we informed them of a GPS failure and requested a heading; so we could troubleshoot the problem to try and fix it.  Shortly thereafter we received a message FMS DR more than 5 minutes.  We determined at this point the GPS off substantially and flew the rest of the way using VORs and green needles. We tried several times to sync the GPS; but the position would not hold.  We contacted the Company to let them know of the situation via ACARS.  No other anomalies occurred.  We don't believe anything could have prevented this from our standpoint.  With a GPS failure of this nature; it was not recognizable until we noticed it didn't seem right as well as ATC discovering the issue.
CRJ-200 Captain experiences a GPS malfunction prior to taxi which is reset by the First Officer. After takeoff the crew and ATC both note the aircraft was not following the RNAV departure. VOR navigation is used to continue to destination.