SMA IN TFC PATTERN AT UNCTLED ARPT HAS NMAC.

Narrative

I WAS RETURNING TO WHEELER AFB FROM THE N AT APPROX XA00 HRS. IT WAS MAY/SUN/93 AND WHEELER TWR IS CLOSED ON SAT AND SUN. AS I APCHED PINEAPPLE INTXN I CALLED MY POS AND INTENT TO LAND ON RWY 6 IN THE BLIND ON 126.30 (CTAF). THEN UPON REACHING LEADER FIELD; I RPTED MY POS AND BEING ESTABLISHED ON A L BASE FOR RWY 6. ALL THE TIME RECEIVING NO OTHER ACFT BROADCASTS. I MADE MY CALL TURNING FINAL FOR RWY 6 AND BEGAN MY DSCNT OUT OF 2000 FT MSL. JUST AFTER BEING ESTABLISHED ON FINAL MY COPLT NOTICED AN ACFT APCHING OUT OF THE S AT OUR 4-5 O'CLOCK POS. AS I LOOKED OVER; THE ACFT WAS ABOUT 100-150 FT BELOW AND 200 FT HORIZ TO OUR POS. AT THIS POINT HE HAD NOTICED US AND BEGAN A TURN TO THE R TO AVOID US. THEN CONTINUED THE TURN BACK TO THE S. (THIS ACFT WAS ON A STANDARD VFR ARR FROM THE S. I WAS ON A STANDARD VFR N ARR BOTH TO RWY 6.) I CONTINUED ON FINAL LNDG ON RWY 6 THEN TAXIED TO THE FUEL PIT. I CALLED FLT SVC ON 122.20 FOR A RADIO CHK AND RECEIVED A LOUD AND CLR. THE OTHER ACFT HAD NOW RETURNED FROM THE S AND AS I TAXIED BACK OUT TO RUN UP FOR MY DEP THE OTHER ACFT NOW BROADCASTING ON 126.30 AND WAS MAKING HIS POS RPTS. I CALLED THE OTHER ACFT. HE APOLOGIZED; SAYING IT WAS HIS FAULT. WE DIDN'T DISCUSS WHETHER HIS RADIO WAS TURNED DOWN; ON THE WRONG SELECT OR WRONG FREQ. I ASSUMED IT WAS 1 OF THE 3. I HAVE A MUCH MORE VIGILANT SCAN OF THE TFC PATTERN NOW; ESPECIALLY WHEN THE RADIOS ARE QUIET. A COPY OF WHEELER AERO CLUB SOP'S FOR ARRS INCLUDED. ALSO; IT MAY BE A GOOD IDEA FOR WHEELER TO HAVE THE STANDARD R HAND TFC PATTERN IN THE SOP FOR TIMES WHEN THE TWR IS NOT IN OP.