WHILE PRACTICING TOUCH-AND-GOES AT AN UNCTLED ARPT; C206 HAS NEAR MISS WITH C172 WHOSE PLT HAD MADE NO CTAF RPTS.

Narrative

I WAS FLYING A C206 AND CONDUCTING LNDG PRACTICE AND TFC PATTERN WORK AT THE ORCAS ISLAND; WA; EAST SOUND ARPT WITH ANOTHER PLT. DURING A GAR PROC ON RWY 16; I MADE THE GAR CALL ON THE CTAF AND BEGAN A CLB. WHILE STILL CLBING TO TFC PATTERN ALT AND APPROX 5 SECONDS AFTER LEVELING THE WINGS ON A XWIND LEG AT APPROX 700 FT WHEN THE PNF IN THE ACFT OBSERVED AN ACFT ENTERING THE TFC PATTERN; STRAIGHT-IN FROM AN EXTENDED DOWNWIND LEG AT THE SAME ALT. THIS ACFT HAD MADE NO RADIO CALLS ON THE CTAF PRIOR TO THE INCIDENT. THE PNF CALLED OUT; 'AIRPLANE; GO DOWN!' I IMMEDIATELY PUSHED THE YOKE FORWARD AND OBSERVED A C172 PASS DIRECTLY OVER US AT A DISTANCE OF APPROX 10 FT. AFTER THE C172 PASSED OVER US; A FEMALE PLT MADE A RADIO CALL ON THE CTAF SAYING 'THE ACFT THAT JUST PASSED UNDER US; I THOUGHT YOU HAD LANDED.' THIS WAS THE FIRST TIME THAT THE ACFT MADE ANY RADIO CALL AT ALL. SHE HAD ENTERED THE TFC PATTERN STRAIGHT-IN FROM AN EXTENDED DOWNWIND LEG AT 300 FT BELOW PATTERN ALT WITHOUT MAKING ANY RADIO CALLS. THE FIRST TA CALL SHE MADE WAS WHEN SHE ENTERED A BASE LEG FOR LNDG AFTER THE INCIDENT. WE WERE SHAKEN UP TO THE POINT THAT WE BOTH DECIDED TO DEPART THE AREA; GO HOME AND QUIT FLYING FOR THE DAY.