NMAC BTWN A PA28 AND A KING AIR; BOTH ON SHORT BASE LEGS TO FINAL FOR RWY 30 AT MLE.

Narrative

BEACHCRAFT KING AIR WAS ENRTE TO MLE TO PICK UP A PAX. PA28-140 WAS ENGAGED IN MULTIPLE TOUCH AND GOES AT MLE FOR STUDENT TRAINING (I WAS THE INSTRUCTOR). ANOTHER ACFT (A PA28R-180) HAD JUST ENTERED THE DOWNWIND FROM A MID-FIELD XWIND; I WAS ENTERING THE DOWNWIND FROM THE L XWIND. THE KING AIR PLT ANNOUNCED ENTERING A 4 MI L BASE; AND ASKED FOR TFC TO RESPOND. BOTH PA'S IN THE PATTERN RESPONDED WITH POS. MY STUDENT BROADCAST MID-FIELD DOWNWIND AND BASE RPTS. THE PA28R-180 WAS NOT FURTHER INVOLVED. UPON ENTERING; AND ANNOUNCING BASE; THE KING AIR ANNOUNCED A 1 MI FINAL. THE STUDENT AT THE CTLS WAS UNAWARE OF ANY OTHER TFC AND WAS CONCENTRATING ON FLYING THE PATTERN AND LNDG. WHEN IT BECAME OBVIOUS THAT THE STUDENT WAS NOT GOING TO RESPOND PROPERLY; I TOOK OVER THE CTLS AND INITIATED A CLBING R TURN TO AVOID THE KING AIR TO MY R ON FINAL. CLOSEST DISTANCE WAS APPROX 100 FT VERT AND 500 FT HORIZ. I CIRCLED BEHIND THE KING AIR; CONTINUED THE APCH; BUT HAD TO GO AROUND BECAUSE HE WAS STILL ON THE RWY. CONSIDERATIONS: 1) NON-STANDARD PATTERN ENTRY BY THE KING AIR; 'BARGING' INTO A FULL PATTERN; 2) A FLT TRAINING SIT WITH A STUDENT WHO FAILED TO RESPOND PROPERLY; 3) DIFFICULTIES IN TIMING THE PATTERN AND IDENTING THE CONFLICTING TFC DUE TO HIS SLIGHTLY MISSTATING DISTANCE (HE WAS ABOUT 6 MI OUT ON INITIAL CALL).