A320 flight crew experience a dual FMGC failure on initial climbout and return to their departure st...

Attributes
ACN	815163
Time
Date	200811
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 38000
Environment
Flight Conditions	IMC
Weather Elements	other
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zzz.artcc tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	815163
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : fmgc other flight crewa
Resolutory Action	flight crew : diverted to alternate
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

During initial climbout; FMGC #2 appeared to partially fail. First officer's map went away on his navigation display and had to match his range distance to captain's side. Attempted to reset FMGC #2 about 4 times per quick reference handbook procedures with no change. Sent an ACARS message to dispatcher as to legality of crossing gulf of mexico with only 1 FMGC. Maintenance told dispatcher to have us return to ZZZ (they remotely had queried the aircraft and determined that both fmgcs were not working correctly). Both fmgcs were replaced in ZZZ; tested; flight then completed. Note: quick reference handbook guidance is so confusing that it's of no operational value. Quick reference handbook addresses 'FMGC failure dual (2).' what is being addressed here? A dual FMGC failure? They why the '1' or '2' in parenthesis? Or do these address a single FMGC failure (1) or (2)? We need very specific guidance in our quick reference handbook to identify a single FMGC failure. How are we to proceed operationally; i.e.; can we continue into 'waters' airspace or conduct CAT ii/III approaches? We also need very specific guidance to address a dual FMGC failure; since the aircraft goes virtually 'nil automation' in such a situation. Our current quick reference handbook pages are so confusing that we weren't even sure if they applied to our situation.

Original NASA ASRS Text

Title: A320 flight crew experience a dual FMGC failure on initial climbout and return to their departure station for repairs.

Narrative: During initial climbout; FMGC #2 appeared to partially fail. First Officer's map went away on his Navigation Display and had to match his range distance to Captain's side. Attempted to reset FMGC #2 about 4 times per Quick Reference Handbook procedures with no change. Sent an ACARS message to Dispatcher as to legality of crossing Gulf of Mexico with only 1 FMGC. Maintenance told Dispatcher to have us return to ZZZ (they remotely had queried the aircraft and determined that both FMGCs were not working correctly). Both FMGCs were replaced in ZZZ; tested; flight then completed. Note: Quick Reference Handbook guidance is so confusing that it's of no operational value. Quick Reference Handbook addresses 'FMGC failure dual (2).' What is being addressed here? A Dual FMGC Failure? They why the '1' or '2' in parenthesis? Or do these address a single FMGC failure (1) or (2)? We need very specific guidance in our Quick Reference Handbook to identify a single FMGC failure. How are we to proceed operationally; i.e.; can we continue into 'waters' airspace or conduct CAT II/III approaches? We also need very specific guidance to address a dual FMGC Failure; since the aircraft goes virtually 'nil automation' in such a situation. Our current Quick Reference Handbook pages are so confusing that we weren't even sure if they applied to our situation.

Data retrieved from NASA's ASRS site as of May 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.