Narrative:

Climbing through approximately 7;000 to 8;000 ft we noticed both navigation displays flickering between 5 and 20 miles off course. As we climbed through 10;000 ft the FMS airspeed was fluctuating between 250 and 310 KTS. I asked the first officer to call maintenance and let them know what was going on and see if they had a solution. While he was speaking with maintenance I asked ATC if he showed us on course. He said we were about on course and I advised that we were having some navigation problems and would like a heading while we spoke to maintenance; shortly after as we climbed through 16;500 I asked to maintain 17;000 or FL180 as I was starting to plan for a return. Maintenance advised to check for tripped circuit breakers which there were none. They advised to return and dispatch agreed under captain's emergency authority and to land at 110;000 pounds or less. We declared emergency and received delaying vectors back to the airport as we were at 111;600 pounds at this time. We landed without incident at 109;600 pounds. After completing the days flying I spoke to maintenance control and they said both vias [versatile integrated avionics] had failed.

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Original NASA ASRS Text

Title: B717 Captain experiences flickering NAV displays and fluctuating FMC airspeed indications. After consulting with Maintenance the Captain elects to return to the departure airport. Maintenance discovers both VIA's have failed.

Narrative: Climbing through approximately 7;000 to 8;000 FT we noticed both NAV Displays flickering between 5 and 20 miles off course. As we climbed through 10;000 FT the FMS airspeed was fluctuating between 250 and 310 KTS. I asked the First Officer to call Maintenance and let them know what was going on and see if they had a solution. While he was speaking with Maintenance I asked ATC if he showed us on course. He said we were about on course and I advised that we were having some navigation problems and would like a heading while we spoke to Maintenance; shortly after as we climbed through 16;500 I asked to maintain 17;000 or FL180 as I was starting to plan for a return. Maintenance advised to check for tripped circuit breakers which there were none. They advised to return and Dispatch agreed under Captain's emergency authority and to land at 110;000 LBS or less. We declared emergency and received delaying vectors back to the airport as we were at 111;600 LBS at this time. We landed without incident at 109;600 LBS. After completing the days flying I spoke to Maintenance Control and they said both VIAs [Versatile Integrated Avionics] had failed.

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.