LR24 ACFT LNDG ON SNOW COVERED PLOWED RWY WITH POOR BRAKING RAN OFF END OF RWY. NO DAMAGE.

Narrative

MEDICAL TRIP FROM APA TO CYS. A LAST MIN ACFT CHANGE DUE TO MECHANICAL WITH FIRST ACFT. THERE WAS A RUSH TO GET EVERYTHING ACCOMPLISHED. WX AT CYS WAS VFR; BUT A SNOWSTORM HAD JUST PASSED. THERE WAS NO BRAKING ACTION RPT FOR EITHER RWY. WE WERE UNABLE TO OBTAIN THE CURRENT WX ENRTE. OUR PLAN WAS TO LAND ON THE RWY WHICH FAVORED THE WIND FROM OUR LAST RPTED WX. THIS FAVORED RWY 30. CLRED FOR THE VISUAL WE MADE THE SWITCH TO CTAF (TWR CLOSED) AND ANNOUNCED OUR INTENTIONS. OVER CTAF CREWS WERE OUT PLOWING SNOW. THEY SAID BOTH RWYS WERE PLOWED. WE CONTINUED FOR RWY 30. TOUCHDOWN WAS NORMAL VREF +5; APPROX 125 KTS. ONCE ON THE RWY SPOILERS WERE DEPLOYED AND MAX BRAKING WAS USED. THRUST REVERSERS WERE NOT INSTALLED. ANTI-SKID WAS WORKING PROPERLY. BRAKING ACTION WAS POOR TO NIL. THE END RESULT WAS WE EXITED STRAIGHT OFF THE END OF THE RWY ABOUT 50 FT. SHUTDOWN AND A WALKAROUND BY THE CAPT WAS MADE. WE ELECTED TO START UP AND TAXI BACK TO THE RWY AND TXWY. NO VISIBLE DAMAGE TO THE ACFT. A THOROUGH WALKAROUND WAS MADE. THE CAPT DETERMINED THE ACFT TO BE AIRWORTHY AND CHOSE TO CONTINUE BACK TO APA. I SHOWED AND VOICED MY CONCERN ABOUT HIS DECISION. RETURN FLT UNEVENTFUL. CONTRIBUTING FACTORS: MY LACK OF EXPERIENCE IN JET ACFT ON SLICK RWYS. NOT OBTAINING UPDATED WX AND RWY CONDITIONS PRIOR TO DEP. CAPT WAS TALKING WITH ATC TO CHANGE THE TAIL NUMBER ON THE FLT PLAN HOME WHILE IN THE APCH PHASE. NO DISCUSSION ON HOW TO FLY THE APCH GIVEN THE CONDITIONS. TECHNIQUE USED IN THE FLARE NOT APPROPRIATE FOR SLICK RWY. MAKING RUSH DECISIONS BECAUSE WE WERE LATE ARRIVING AND NOT ELECTING TO GAR. A MAINT INSPECTION WAS DONE ON THE ACFT BACK AT APA. NO PROBS WERE FOUND. THERE WERE NO INJURIES WHATSOEVER TO ANY PERSON ONBOARD THE ACFT.