A319 captain reported diverting to an alternate after loss of FMGC number 2.

Attributes
ACN	1314381
Time
Date	201512
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Make Model Name	A319
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Flight Plan	IFR
Component
Aircraft Component	FMS/FMC
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 162
Events
Anomaly	Aircraft Equipment Problem Less Severe Inflight Event / Encounter Fuel Issue

Narrative:

While en route; FL370; halfway; FMGC 2 failed. First officer (first officer) performed system reset with no luck. Captains FMGC displayed independent operation; while first officer had nothing. 1fd1 was displayed; so first officer was slaved to captain. First officer unable to use FMGC; ACARS was only available. Weather at time was 300 and 1. We continued and both captain and first officer had no concerns about completing the approach and normal landing. ATC vectored us to ILS 22; short turn 10 mile final. Went to arm the approach; approach button inop; unable to couple to the ILS. Only thing to do kick off autopilot; raw data hand flown. This was all by surprise. First officer had nothing on his instruments; looked to mine and helped to about 400 ft when my comfort level of safety was exceeded. Went around; needed VMC weather. [Diversion airport] was chosen for good weather and passenger care. Declared min fuel and asked for priority handling. We canceled min fuel as we approached. Landed without incident.

Original NASA ASRS Text

Title: A319 Captain reported diverting to an alternate after loss of FMGC Number 2.

Narrative: While en route; FL370; halfway; FMGC 2 failed. FO (First Officer) performed system reset with no luck. Captains FMGC displayed independent operation; while FO had nothing. 1FD1 was displayed; so FO was slaved to Captain. FO unable to use FMGC; ACARS was only available. Weather at time was 300 and 1. We continued and both Captain and FO had no concerns about completing the approach and normal landing. ATC vectored us to ILS 22; short turn 10 mile final. Went to arm the approach; approach button inop; unable to couple to the ILS. Only thing to do kick off autopilot; raw data hand flown. This was all by surprise. FO had nothing on his instruments; looked to mine and helped to about 400 ft when my comfort level of safety was exceeded. Went around; needed VMC weather. [Diversion airport] was chosen for good weather and passenger care. Declared min fuel and asked for priority handling. We canceled min fuel as we approached. Landed without incident.

Data retrieved from NASA's ASRS site 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.