B737 captain reported temporary dual FMC failure.

Attributes
ACN	1506944
Time
Date	201712
Local Time Of Day	1801-2400
Environment
Light	Night
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Cruise
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 397 Flight Crew Type 14000
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

Dual FMC failure while at cruise for about 30 seconds. LNAV; VNAV; autothrottle disengaged; FMC's went blank then returned without the option to select the FMC mode. Everything returned before we could even select a checklist. Reengaged all modes and they worked properly for the rest of the flight. Dispatch and maintenance were both notified.

Original NASA ASRS Text

Title: B737 Captain reported temporary dual FMC failure.

Narrative: Dual FMC failure while at cruise for about 30 seconds. LNAV; VNAV; Autothrottle disengaged; FMC's went blank then returned without the option to select the FMC mode. Everything returned before we could even select a checklist. Reengaged all modes and they worked properly for the rest of the flight. Dispatch and Maintenance were both notified.

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.