A320 crew has dual FMGC glitch during yosem 1 arrival to sfo.

Attributes
ACN	733111
Time
Date	200703
Local Time Of Day	1201 To 1800
Place
Locale Reference	intersection : snora
State Reference	CA
Altitude	msl single value : 30000
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	artcc : zoa.artcc
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Route In Use	arrival star : yosem1
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 100 flight time total : 10000 flight time type : 400
ASRS Report	733111
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance none taken : insufficient time
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

FMGC 1 froze and we could not update SID. While trying to use mcdu 1 it froze for FMGC inputs. Tried mcdu 2 -- it all froze for inputs. When we got to snora aircraft went to heading mode and we overshot our turn. ZOA gave us a vector to correct. We told ATC we needed vectors for a visual approach into sfo. They gave us vectors to visual runway 28R. We landed without incident. Maintenance reset and fixed aircraft at the gate.

Original NASA ASRS Text

Title: A320 CREW HAS DUAL FMGC GLITCH DURING YOSEM 1 ARR TO SFO.

Narrative: FMGC 1 FROZE AND WE COULD NOT UPDATE SID. WHILE TRYING TO USE MCDU 1 IT FROZE FOR FMGC INPUTS. TRIED MCDU 2 -- IT ALL FROZE FOR INPUTS. WHEN WE GOT TO SNORA ACFT WENT TO HDG MODE AND WE OVERSHOT OUR TURN. ZOA GAVE US A VECTOR TO CORRECT. WE TOLD ATC WE NEEDED VECTORS FOR A VISUAL APCH INTO SFO. THEY GAVE US VECTORS TO VISUAL RWY 28R. WE LANDED WITHOUT INCIDENT. MAINT RESET AND FIXED ACFT AT THE GATE.

Data retrieved from NASA's ASRS site as of January 2009 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.