PA31 PLT EXECUTES A GAR AFTER REALIZING THE LNDG GEAR IS NOT EXTENDED.

Narrative

I WAS ON A L DOWNWIND FOR RWY 8 AT 1000 FT MSL WHEN I WAS WARNED ABOUT A KING AIR DSNDING FROM 4000 FT MSL THAT WOULD CROSS AT MY 11-12 O'CLOCK POS. I DID NOT SEE THE KING AIR UNTIL HE ENTERED A L BASE FOR RWY 8 AT WHICH TIME I WAS TURNING DOWNWIND TO BASE. I THEN EXTENDED MY DOWNWIND ONLY TO FIND A HELI AT LESS THAN 1/2 MI AND ABOUT THE SAME ALT. I TURNED MY BASE AND HEARD THE KING AIR CALL OUT VERY ROUGH WINDSHEAR CLOSE TO THE APCH END VARIOUS FROM +10 TO -10 KTS IN SPD. I THEN FOUND MYSELF FOCUSED ON TFC AND THE WINDSHEAR AND NOT ON MY CHKLISTS TO LAND. WHEN I TURNED FINAL; THE WIND AND TURB WAS VERY ROUGH AND I WAS GETTING SPD VARIANCE FROM +15 TO -15 KTS AND CALLED THAT OUT TO TWR. AS I APCHED OVER THE APCH END OF RWY 8; A CITATION JET WAS HOLDING SHORT AWAITING MY ARR. I THEN REALIZED MY GEAR WAS NOT DOWN AND LOCKED. AS I STARTED MY GAR; THE CITATION JET CALLED OUT 'LNDG TFC; YOUR GEAR IS NOT DOWN.' THEN TWR TOLD ME TO GO AROUND. I THEN ACKNOWLEDGED THAT I ALREADY STARTED MY GAR AND WOULD RPT MY DOWNWIND. I FEEL THAT THE AMOUNT OF WORKLOAD ON MYSELF WAS OVERWHELMING AND THAT WAS THE MAIN CONTRIBUTING FACTOR TO THIS INCIDENT.