Narrative:

I was flying a citation excel to iad. I was captain with a new hire first officer, we had a full written route briefing from our company dispatcher, had contacted the AFSS in florida and leesburg, va, and had called the control tower prior to departure and had been uniformly and consistently given the same runway conditions at iad, 1 inch packed snow on the runway with braking action fair. At approximately XA00E (XA00Z) we were on final approach, and again were told the braking action was fair. When we landed on runway 1R, it was dark, and we found that on top of the 1 inch of packed snow there was 3-4 inches of loose snow. Further, airliners that had landed before us had left ruts, grooves, and ridges in the snow, some ridges being 6 inches deep or so. After touchdown, our main gear felt as if it caught a rut or ridge on one side or the other, and the nose started moving to the left. I straightened out the nose, but the mains broke traction, and the airplane slid off the left edge of the runway. The left wing came to rest on top of 4-5 inches of snow, with the right main gear still on the pavement. We shut down the engines, left the APU running until help arrived, at which time, we evacuate/evacuationed through the emergency exit over the right wing. We had 2 passenger on board, no one was injured at all. I took photographs of the runway condition, and the people who drove out to us were amazed that aircraft were being cleared to land on a runway with so much snow on it. I believe the cause of the accident was the continued inaccurate runway condition reports we received. We had plenty of fuel on board for holding, and had we known the true conditions, we would have held while the runway was plowed, used runway 1L or diverted. In the future, more accurate runway conditions should be disseminated.

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Original NASA ASRS Text

Title: EXPECTING THE RPTED 1 INCH OF PACKED SNOW ON RWY 1R AT KIAD, A CITATION PLT IS SURPRISED BY RUTTED CONDITIONS AND UP TO 4 INCHES OF LOOSE SNOW ON TOP OF THAT. ACFT CTL IS LOST ON LNDG, AND THE END OF THE FLT IS OFF THE RWY IN 4-5 FT OF SNOW.

Narrative: I WAS FLYING A CITATION EXCEL TO IAD. I WAS CAPT WITH A NEW HIRE FO, WE HAD A FULL WRITTEN RTE BRIEFING FROM OUR COMPANY DISPATCHER, HAD CONTACTED THE AFSS IN FLORIDA AND LEESBURG, VA, AND HAD CALLED THE CTL TWR PRIOR TO DEP AND HAD BEEN UNIFORMLY AND CONSISTENTLY GIVEN THE SAME RWY CONDITIONS AT IAD, 1 INCH PACKED SNOW ON THE RWY WITH BRAKING ACTION FAIR. AT APPROX XA00E (XA00Z) WE WERE ON FINAL APCH, AND AGAIN WERE TOLD THE BRAKING ACTION WAS FAIR. WHEN WE LANDED ON RWY 1R, IT WAS DARK, AND WE FOUND THAT ON TOP OF THE 1 INCH OF PACKED SNOW THERE WAS 3-4 INCHES OF LOOSE SNOW. FURTHER, AIRLINERS THAT HAD LANDED BEFORE US HAD LEFT RUTS, GROOVES, AND RIDGES IN THE SNOW, SOME RIDGES BEING 6 INCHES DEEP OR SO. AFTER TOUCHDOWN, OUR MAIN GEAR FELT AS IF IT CAUGHT A RUT OR RIDGE ON ONE SIDE OR THE OTHER, AND THE NOSE STARTED MOVING TO THE L. I STRAIGHTENED OUT THE NOSE, BUT THE MAINS BROKE TRACTION, AND THE AIRPLANE SLID OFF THE L EDGE OF THE RWY. THE L WING CAME TO REST ON TOP OF 4-5 INCHES OF SNOW, WITH THE R MAIN GEAR STILL ON THE PAVEMENT. WE SHUT DOWN THE ENGS, LEFT THE APU RUNNING UNTIL HELP ARRIVED, AT WHICH TIME, WE EVACED THROUGH THE EMER EXIT OVER THE R WING. WE HAD 2 PAX ON BOARD, NO ONE WAS INJURED AT ALL. I TOOK PHOTOGRAPHS OF THE RWY CONDITION, AND THE PEOPLE WHO DROVE OUT TO US WERE AMAZED THAT ACFT WERE BEING CLRED TO LAND ON A RWY WITH SO MUCH SNOW ON IT. I BELIEVE THE CAUSE OF THE ACCIDENT WAS THE CONTINUED INACCURATE RWY CONDITION RPTS WE RECEIVED. WE HAD PLENTY OF FUEL ON BOARD FOR HOLDING, AND HAD WE KNOWN THE TRUE CONDITIONS, WE WOULD HAVE HELD WHILE THE RWY WAS PLOWED, USED RWY 1L OR DIVERTED. IN THE FUTURE, MORE ACCURATE RWY CONDITIONS SHOULD BE DISSEMINATED.

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.