Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Workload; Human-Machine Interface; Confusion; Distraction
Aircraft Equipment Problem Critical
Flight Crew FLC complied w / Automation / Advisory; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action; General Declared Emergency
Procedure; Aircraft; Chart Or Publication
Thirty five minutes after departure and level at FL330; observed numerous level 1 and 2 alerts as well as loss of all FMS navigation and way points. All system quantities and numeric values had X's displayed and all systems with L/R sides (not any engine indications) indicated that the Left side had failed. Advised ATC of our loss of primary navigation and continued our present heading via ATC instructions. We took the next several minutes to assess the alerts and figure out what had actually failed and what was a false indication. Having figured out that several indicated failures were incorrect and assessing that what had failed had a functioning back up system or wouldn't affect us either way with our airport/runway landing choice; with VMC conditions existing from our current position all the way to our destination and with several items to still address and communications to make. Our filed destination was the closest; safest airport in point of time. Given our current status we declared emergency and received clearance via radar vectors (while the #2 VOR was available for enroute navigation; given the task saturation we were experiencing; I elected to request vectors all the way in for the visual approach). We notified Dispatch via ACARS and spoke with Maintenance Control. We asked for any guidance for our given condition and was told to follow our VIA fail checklist (that doesn't exist). One piece of information Maintenance did provide when asked was that the landing gear console lights 'should' illuminate indicating a down and locked condition (they were right/had 3 green for landing). We felt that the flaps/slats and landing gear would operate normally but wouldn't have any indication (PSEU fault). With that in mind we requested a visual approach to 27R and to have the fire trucks standing by. In speaking with the flight attendants: I informed them of our status and that we would have the safety equipment standing by but to expect a normal landing and that I would let them know if anything changed. I made a PA to the passengers as well with the same message. We had to use the QRH performance section to figure Vref/app speeds as that function of the MS didn't work. Since the First Officer could manually tune the LOC/course we decided he would fly the approach and I would make the landing. Having made a visual approach to a landing and with no irregularities noted by us; Tower or the fire trucks; we taxied to the gate where we were met by maintenance personnel.It was determined that VIA 1 fail and according to the Mechanic another internal failure that had yet to be identified when I left the aircraft.
A B717 Via (Versatile Integrated Avionics) 1 failed in flight resulting in the loss of critical flight information so an emergency was declared and the flight continued to its filed destination.