Narrative:

Taxi in was treacherous. Blue lights were occasionally, sporadically obscured by snow and blowing snow and deep snow drifts. Airport signage was missing (per united states standards) or obscured, making taxi in a slow, tedious process. After servicing, the aircraft was pushed back from gate onto north end of ramp facing west for deicing. The process was slow due to WX, and during that time plowing operations were in progress on txwys. After engine start we were cleared to taxi to runway 36. We proceeded off the ramp taxiway west, left on taxiway H. Initially the txwys looked bare on taxiway west and taxiway H, but once established on taxiway H sbound, the pavement disappeared causing reliance on blue lights to maintain path. (Note all lights, wing and nosewheel were on as aids at this point). Snow was blowing at 20-30 mph from west. When south on taxiway H, the initial taxi check was run and we began looking for the dogleg on taxiway H to the southeast. I saw a 'clear' line of lights to the southeast and proceeded to keep them on my left. Many other lights were visible past this line and more visible before it. Just then the copilot noted a taxi light on his right. It appeared to be too close to the aircraft. He so remarked and I stopped. At that point the nosewheel and perhaps main gear had left the pavement. The problem was clear after we sat there several hours that all the lights on the left edge of the dogleg were buried under snow. As the plane came by and cleared the area they began to show up, but on taxi out they were 100 percent obscured at that point. So what appeared to be the left side of the taxiway was really the right side. In essence, I missed the turn and had continued straight ahead off the taxiway. The rest of the story was simply shut down engines and wait for busses to deplane the passenger. No injuries (very smooth taxiway departures), no known aircraft damage -- snow was soft. Just couldn't move any more after stopping.

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Original NASA ASRS Text

Title: EXCURSION FROM TXWY DURING A TAXI OP IN A SNOW STORM.

Narrative: TAXI IN WAS TREACHEROUS. BLUE LIGHTS WERE OCCASIONALLY, SPORADICALLY OBSCURED BY SNOW AND BLOWING SNOW AND DEEP SNOW DRIFTS. ARPT SIGNAGE WAS MISSING (PER UNITED STATES STANDARDS) OR OBSCURED, MAKING TAXI IN A SLOW, TEDIOUS PROCESS. AFTER SVCING, THE ACFT WAS PUSHED BACK FROM GATE ONTO N END OF RAMP FACING W FOR DEICING. THE PROCESS WAS SLOW DUE TO WX, AND DURING THAT TIME PLOWING OPS WERE IN PROGRESS ON TXWYS. AFTER ENG START WE WERE CLRED TO TAXI TO RWY 36. WE PROCEEDED OFF THE RAMP TXWY W, L ON TXWY H. INITIALLY THE TXWYS LOOKED BARE ON TXWY W AND TXWY H, BUT ONCE ESTABLISHED ON TXWY H SBOUND, THE PAVEMENT DISAPPEARED CAUSING RELIANCE ON BLUE LIGHTS TO MAINTAIN PATH. (NOTE ALL LIGHTS, WING AND NOSEWHEEL WERE ON AS AIDS AT THIS POINT). SNOW WAS BLOWING AT 20-30 MPH FROM W. WHEN S ON TXWY H, THE INITIAL TAXI CHK WAS RUN AND WE BEGAN LOOKING FOR THE DOGLEG ON TXWY H TO THE SE. I SAW A 'CLR' LINE OF LIGHTS TO THE SE AND PROCEEDED TO KEEP THEM ON MY L. MANY OTHER LIGHTS WERE VISIBLE PAST THIS LINE AND MORE VISIBLE BEFORE IT. JUST THEN THE COPLT NOTED A TAXI LIGHT ON HIS R. IT APPEARED TO BE TOO CLOSE TO THE ACFT. HE SO REMARKED AND I STOPPED. AT THAT POINT THE NOSEWHEEL AND PERHAPS MAIN GEAR HAD LEFT THE PAVEMENT. THE PROB WAS CLR AFTER WE SAT THERE SEVERAL HRS THAT ALL THE LIGHTS ON THE L EDGE OF THE DOGLEG WERE BURIED UNDER SNOW. AS THE PLANE CAME BY AND CLRED THE AREA THEY BEGAN TO SHOW UP, BUT ON TAXI OUT THEY WERE 100 PERCENT OBSCURED AT THAT POINT. SO WHAT APPEARED TO BE THE L SIDE OF THE TXWY WAS REALLY THE R SIDE. IN ESSENCE, I MISSED THE TURN AND HAD CONTINUED STRAIGHT AHEAD OFF THE TXWY. THE REST OF THE STORY WAS SIMPLY SHUT DOWN ENGS AND WAIT FOR BUSSES TO DEPLANE THE PAX. NO INJURIES (VERY SMOOTH TXWY DEPS), NO KNOWN ACFT DAMAGE -- SNOW WAS SOFT. JUST COULDN'T MOVE ANY MORE AFTER STOPPING.

Data retrieved from NASA's ASRS site as of July 2007 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.