INSTRUCTOR WITH SPI HAS WINGTIP HIT PROP OF PARKED PLANE AS THEY SKID ON ICE TRYING TO STOP ACFT.

Narrative

A STUDENT PLT AND I WERE TAXIING AN SMA X BACK TO THE PARKING AREA AT THE END OF OUR FLT. THE TAXI (RAMP) AREA WAS ICY IN SPOTS AND SNOW COVERED IN OTHERS; HOWEVER; THE CONDITIONS WERE NOT SUCH TO PREVENT A STUDENT PLT FROM TAXIING THE ACFT INTO THE TIEDOWN AREA DESIGNATED TO OUR FLYING CLUB. THE TAXI LANE TO THIS PARTICULAR TIEDOWN AREA IS APPROX 45 FT WIDE WITH A CTRLINE PAINTED IN THE MIDDLE. THE ARPT AUTHORITY HAS A POLICY OF PLOWING SNOW INTO THE CTR OF THIS 45 FT WIDE TAXI LANE. AFTER THE LAST SNOWFALL; THE SNOW AS PLOWED WELL OFF-CTR OF THE MIDDLE OF THE TAXI LANE SO THAT 1 SIDE WAS APPROX 5 FT NARROWER THAN THE OTHER. THE SNOW PILE ON THIS MORNING WAS APPROX 5 FT WIDE AND 2 FT HIGH. MY STUDENT AND I WERE ON THE NARROW SIDE OF THE TAXI LANE BECAUSE OUR TIEDOWN SLOT WAS SITUATED THERE. THE ARPT AUTHORITY HAS REPEATEDLY CREATED A HAZARDOUS SIT BY PLOWING SNOW TO THE CTR OF THE TAXI LANES RATHER THAN CLR OF ACTIVE AREAS. ON THE MORNING OF THIS OCCURRENCE; THE POOR CONDITIONS WERE EXACERBATED BY THE FACT THAT THE PILE OF SNOW AS APPROX 5 FT OFF-CTR. MY STUDENT AND I TRAVELED APPROX 175 FT PAST 4 OTHER SMALL ACFT WITHOUT BEING UNSAFELY CLOSE TO THOSE ACFT. AS WE WERE TAXIING CLOSER TO OUR TIEDOWN SLOT; ANOTHER INSTRUCTOR WAS STANDING IN THE TIEDOWN AREA PREFLTING AN SMA Y; A MUCH LARGER ACFT THAN THE SMA Z WE HAD ALREADY PASSED. THE PROP BLADE OF THE SMA Y WAS TILTED IN AN UPWARD POS RATHER THAN HORIZ (PARALLEL TO THE GND). I NOTICED THAT THE BLADE OF THE LARGER ACFT COULD POSSIBLY COME INTO CONTACT WITH THE WINGTIP OF OUR ACFT DUE TO THE CLOSE QUARTERS CREATED BY THE OFF-CTR SNOW PILE; THEREFORE; I INSTRUCTED MY STUDENT TO STOP IMMEDIATELY. AS HE APPLIED THE BRAKES; THE PLANE SLID FORWARD AND TO THE R ON AN ICY SPOT. AS A RESULT OF NOT BEING ABLE TO STOP IN A SHORT ENOUGH DISTANCE DUE TO THE ICE AND THE TIGHT QUARTERS; THE SMA Y PROP BLADE CAUGHT THE UNDERSIDE OF OUR R WINGTIP AND CUT INTO THE WINGTIP SKIN CAUSING AN OPENING APPROX 6 INCHES LONG.