Narrative:

Taxi route to runway was blocked by snow. Taxied to a midfield intersecting taxiway for taxi back. Stuck to left side of runway on taxi back because it's easier to judge position of left main relative to snow banks on left. Snow banks blocked 15-25 ft of runway width. Made right 180 degree to position for takeoff. This also would allow nosewheel to use extra pavement width of entrance taxiway to right front. Edge of runway I was turning towards was obscured by shallow snow with more snow banks just beyond. Turn radius of nosewheel was 1-2 ft wider than available pavement. This was my first 180 degree turn on a runway in an medium large transport since transitioning from large transport. Should have waited for a better time to try it.

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Original NASA ASRS Text

Title: CAPT OF ACR MLG ACFT INADVERTENTLY TAXIED OFF RWY EDGE DUE TO SNOW ON RWY DURING TAXI FOR TKOF.

Narrative: TAXI RTE TO RWY WAS BLOCKED BY SNOW. TAXIED TO A MIDFIELD INTERSECTING TXWY FOR TAXI BACK. STUCK TO L SIDE OF RWY ON TAXI BACK BECAUSE IT'S EASIER TO JUDGE POS OF L MAIN RELATIVE TO SNOW BANKS ON L. SNOW BANKS BLOCKED 15-25 FT OF RWY WIDTH. MADE R 180 DEG TO POS FOR TKOF. THIS ALSO WOULD ALLOW NOSEWHEEL TO USE EXTRA PAVEMENT WIDTH OF ENTRANCE TXWY TO R FRONT. EDGE OF RWY I WAS TURNING TOWARDS WAS OBSCURED BY SHALLOW SNOW WITH MORE SNOW BANKS JUST BEYOND. TURN RADIUS OF NOSEWHEEL WAS 1-2 FT WIDER THAN AVAILABLE PAVEMENT. THIS WAS MY FIRST 180 DEG TURN ON A RWY IN AN MLG SINCE TRANSITIONING FROM LGT. SHOULD HAVE WAITED FOR A BETTER TIME TO TRY IT.

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.