Narrative:

Upon checking in with the control tower at cgf, the tower advised us that the runway had just been plowed, there was a thin layer of packed snow on the runway and mu readings for runway 5 were 65/60/55. We touched down 'on speed' and on the touchdown zone. Initial brake application indicated 'fair' braking action, but approximately 500 ft later, braking action became 'nil.' approximately 1/2 way down the runway, at about 70 KIAS, the captain shut both engines down to eliminate residual thrust being produced at idle. No thrust reversers are installed on this airplane. Nearing the end of the runway, the captain initiated a left turn to avoid impact with the runway end lights and approach lights beyond. A sideways slide resulted, somewhat under 'control.' the aircraft exited the runway to the side, onto a taxiway at the end, and off the taxiway. We ended up about 20 ft off the end of the runway. No injuries or damage resulted. No emergency vehicles responded. Captain started engines and taxied in.

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Original NASA ASRS Text

Title: CAPT OF A CPR MU300 LOST ACFT CTL WHEN ATTEMPTING TO TURN OFF AT THE END OF AN ICY RWY. THE ACFT SLID SIDEWAYS OFF THE END OF THE RWY AND ADJACENT TXWY.

Narrative: UPON CHKING IN WITH THE CTL TWR AT CGF, THE TWR ADVISED US THAT THE RWY HAD JUST BEEN PLOWED, THERE WAS A THIN LAYER OF PACKED SNOW ON THE RWY AND MU READINGS FOR RWY 5 WERE 65/60/55. WE TOUCHED DOWN 'ON SPD' AND ON THE TOUCHDOWN ZONE. INITIAL BRAKE APPLICATION INDICATED 'FAIR' BRAKING ACTION, BUT APPROX 500 FT LATER, BRAKING ACTION BECAME 'NIL.' APPROX 1/2 WAY DOWN THE RWY, AT ABOUT 70 KIAS, THE CAPT SHUT BOTH ENGS DOWN TO ELIMINATE RESIDUAL THRUST BEING PRODUCED AT IDLE. NO THRUST REVERSERS ARE INSTALLED ON THIS AIRPLANE. NEARING THE END OF THE RWY, THE CAPT INITIATED A L TURN TO AVOID IMPACT WITH THE RWY END LIGHTS AND APCH LIGHTS BEYOND. A SIDEWAYS SLIDE RESULTED, SOMEWHAT UNDER 'CTL.' THE ACFT EXITED THE RWY TO THE SIDE, ONTO A TXWY AT THE END, AND OFF THE TXWY. WE ENDED UP ABOUT 20 FT OFF THE END OF THE RWY. NO INJURIES OR DAMAGE RESULTED. NO EMER VEHICLES RESPONDED. CAPT STARTED ENGS AND TAXIED IN.

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.