Narrative:

We had departed 9g0 for a VFR training flight 10 mi to the southwest. Upon returning to 9g0, the bright afternoon sun, which had partially melted some of the packed snow and ice on the runway, was now much lower in the sky, and temperatures had dropped by several degrees. Upon touchdown on runway 24, the aircraft slid to the left side of the runway, apparently pushed by a sudden crosswind. All efforts by me and my student to straighten out and remain on the runway were in vain, and the aircraft continued through the snow bank at the left side of the runway and came to rest in the snow covered grass. As a result of the sudden deceleration while passing through the snow bank, the aircraft nosed down and sustained a bent propeller. There was also minor damage to its right wingtip fairing due to the gust upset. I believe the root cause of this incident was the refreezing of previously melted snow and ice on the runway combined with an unexpected crosswind at touchdown. (Winds had been light and variable for most of the afternoon). I would also theorize that we might have unknowingly had a frozen brake in-flight, which would account for the aircraft resisting our efforts at keeping it on the runway after touchdown.

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Original NASA ASRS Text

Title: A C172 ON A TRAINING FLT SLIDES SIDEWAYS OFF RWY 24. ICE HAD FORMED ON THE MELTED SNOW AT 9G0, NY.

Narrative: WE HAD DEPARTED 9G0 FOR A VFR TRAINING FLT 10 MI TO THE SW. UPON RETURNING TO 9G0, THE BRIGHT AFTERNOON SUN, WHICH HAD PARTIALLY MELTED SOME OF THE PACKED SNOW AND ICE ON THE RWY, WAS NOW MUCH LOWER IN THE SKY, AND TEMPS HAD DROPPED BY SEVERAL DEGS. UPON TOUCHDOWN ON RWY 24, THE ACFT SLID TO THE L SIDE OF THE RWY, APPARENTLY PUSHED BY A SUDDEN XWIND. ALL EFFORTS BY ME AND MY STUDENT TO STRAIGHTEN OUT AND REMAIN ON THE RWY WERE IN VAIN, AND THE ACFT CONTINUED THROUGH THE SNOW BANK AT THE L SIDE OF THE RWY AND CAME TO REST IN THE SNOW COVERED GRASS. AS A RESULT OF THE SUDDEN DECELERATION WHILE PASSING THROUGH THE SNOW BANK, THE ACFT NOSED DOWN AND SUSTAINED A BENT PROP. THERE WAS ALSO MINOR DAMAGE TO ITS R WINGTIP FAIRING DUE TO THE GUST UPSET. I BELIEVE THE ROOT CAUSE OF THIS INCIDENT WAS THE REFREEZING OF PREVIOUSLY MELTED SNOW AND ICE ON THE RWY COMBINED WITH AN UNEXPECTED XWIND AT TOUCHDOWN. (WINDS HAD BEEN LIGHT AND VARIABLE FOR MOST OF THE AFTERNOON). I WOULD ALSO THEORIZE THAT WE MIGHT HAVE UNKNOWINGLY HAD A FROZEN BRAKE INFLT, WHICH WOULD ACCOUNT FOR THE ACFT RESISTING OUR EFFORTS AT KEEPING IT ON THE RWY AFTER TOUCHDOWN.

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.