ACR MLG ENTERED ADJACENT CTLR'S AIRSPACE WITHOUT COORD OR HANDOFF AND CONFLICTED WITH TRAFFIC IN THAT CTLR'S SECTOR.

Narrative

AT XA00Z; MLG X CHKED IN WITH ME AT SLI 145 DEG R/10 DME HDG 020 DEGS AT 5000' MSL; LNDG SNA. THIS WAS DURING HVY TFC CONDITIONS WITH A HDOF PERSON. THE NEXT XMISSION FROM MLG X WAS AT XA06Z; 10 MI SW OF ONT AT 5000'. THERE WAS NO ARTS TAG OR TRANSPONDER AT THIS POS; ONLY A PRIMARY RADAR PRESENTATION. A POINTOUT WAS MADE FROM COAST TO ONT. ONT DID NOT OBSERVE A TARGET OR TRANSPONDER AT THIS POINT. THE STRIP WAS LOCATED IN THE FILE BOX. TRANSPONDER CODE WAS VERIFIED; AND TRANSPONDER REAPPEARED AT THIS TIME. THEN ONT TRACON RESPONDED TO FINDING THIS TRANSPONDER CODE. PLT STATED THERE HAD BEEN A PROB WITH TRANSPONDER IN MORNING. CIRCUMSTANCES: FAILED TRANSPONDER; STRIP ACCIDENTALLY FILED AWAY BY HDOF PERSON; HDOF DROPPED FROM COAST TAB LIST; HVY TFC; RADAR PERSON WAS IN HIS FIFTH HR OF HIS SIXTH DAY OF 6 DAYS SCHEDULED--THIS SIXTH DAY WAS HIS FIFTEENTH SCHEDULED OVERTIME IN A ROW. HIS LAST 2 DAY WEEKEND WAS THE FIRST WK IN APRIL WHILE ON VACATION. THAT'S 25 OVERTIME DAYS SINCE 1/88; ONT TRACON DID NOT PROTECT 5000' AFTER THE INCIDENT RPTED; RESULTING IN OPERROR WITH AN SMA Y AT 5000' (2 1/2 MI; SAME ALT). CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: WHEN THE ARTS HDOF WAS TAKEN BY THE RPTR; EVERYTHING ABOUT THE ARTS TAG WAS NORMAL. ALMOST IMMEDIATELY; THE TRANSPONDER OF THE ACR MLG FAILED AND THE ARTS TAG WENT INTO COAST AND INTO THE COAST LIST. THE HDOF CTLR SAW THE ID IN THE COAST LIST. HE ASSUMED THAT THE CTLR HAD CLRED THE ACFT FOR APCH AND GIVEN A FREQ CHG TO SNA TWR. HE THEN TOOK THE FLT PROGRESS STRIP FOR THE FLT AND FILED IT AWAY. WITH NO STRIP IN FRONT OF HIM AND NO ARTS TAG ON THE MLG TARGET; RPTR FORGOT ABOUT THE FLT UNTIL THE PLT CALLED TO ASK ABOUT A TURN TO THE FINAL APCH COURSE. RPTR STATED THAT THE TFC VOL WAS VERY HIGH AT THE TIME; AND THAT HE DID NOT HAVE TIME TO DEVOTE MUCH ATTN TO THE MLG.