ACR WDB TAXIING TO THE GATE INGESTED ENOUGH SNOW TO CAUSE AN AUTO SHUTDOWN.

Narrative

AFTER TURNING ONTO THE PARALLEL TAXIWAY OF RWY 11L AT MINNEAPOLIS ARPT AND TAXIING WBOUND; THE WDB'S #4 ENG INADVERTENTLY SHUTDOWN. IT WAS TOTALLY DARK OUTSIDE; BUT VISIBILITY WAS OK. THE CAPT WHO WAS TAXIING THE ACFT HAD JUST SHUT DOWN THE #3 ENG WHILE I (COPLT) WAS COMPLETING THE 'AFTER LNDG CHKLIST.' AT THIS TIME; WE NOTICED THE #4 ENG WAS ALSO SHUTDOWN; BUT WITH NO OTHER ABNORMAL INDICATIONS. ONCE AT THE GATE AND PARKED; THE CAPT WENT OUTSIDE TO LOOK AT THE #4 ENG. I WENT DOWN ALSO; AND THERE APPEARED TO BE A LIGHT COATING OF SNOW ON THE BOTTOM OF THE ENG INLET. WE BOTH THOUGHT THAT THE ENG; WHICH WAS OVERHANGING SNOW ON THE AIRFIELD WHILE TAXIING; HAD INGESTED A SMALL AMOUNT OF SNOW AND HAD AUTO-SHUTDOWN WHILE IT WAS AT IDLE. THE CAPT ELECTED NOT TO WRITE THIS UP IN THE LOGBOOK; BECAUSE HE DIDN'T BELIEVE THERE WAS ANY PROBLEM WITH THE ENG. THE NEXT DAY; I HEARD FROM MAINT THAT A LARGE AMOUNT OF SNOW HAD BEEN INGESTED AND THAT THERE WAS EXTENSIVE MAINT REQUIRED. AT THAT TIME; I WAS CERTAIN THAT THE ENG SHUTDOWN SHOULD HAVE BEEN WRITTEN UP THE NIGHT BEFORE; AND I SHOULD HAVE MORE VIGOROUSLY URGED THE CAPT TO DO SO. I ALSO REALIZED THAT THE #4 ENG HAD PROBABLY COME VERY CLOSE TO ONE OF THE SNOW BANKS ON THE TAXIWAY; EVEN THOUGH THE CAPT WAS ALWAYS ON THE YELLOW LINE. BEING DARK AND HAVING NO LIGHTS ON THE SNOW BANKS IT WAS IMPOSSIBLE TO TELL HOW HIGH THEY WERE OR EVEN THAT THERE WAS A PROBLEM.