BE18 HAD AN NMAC WITH A BE20 IN HHR CLASS D AIRSPACE.

Narrative

DURING OP IN CLASS B AIRSPACE; I WAS FLYING ACFT ABCD. I OPERATE UNDER AN INSECT CTL PROJECT. I WAS WORKING AN AREA OF N/S PASSES BTWN THE 110 FREEWAY AND THE 710 FREEWAY. THE SOUTHERN BORDER IS THE 105 FREEWAY. AT THE SOUTHERN BOUNDARY; ON THE WESTERN PART OF THE REGION; THE LAX CLASS B AIRSPACE ENDS AND THE CLASS D AIRSPACE OF HAWTHORNE BEGINS. WHILE OPERATING; I WAS IN DIRECT COM WITH LAX TWR FREQ. THE INCIDENT OCCURRED WHILE HDG SBOUND. THIS IS FOLLOWED BY A L TURN AT THE BORDER TO GO NBOUND. THE PASS ENDS AT THE BORDER OF WHERE CLASS B SURFACE AREA ENDS; AND THE CLASS D BEGINS. THE L TURN WAS INITIATED WHEN SHORTLY AFTER VISUAL WITH A KING AIR ON APCH TO HAWTHORNE WAS ESTABLISHED. I FELT IT SAFER TO CONTINUE THE L TURN AND FELT NO OTHER DEV OR ACTION WAS NECESSARY. OP WAS RESUMED AND CONTACT WITH LAX TWR WAS MAINTAINED. AT NO TIME WAS I MADE AWARE OF THE KING AIR ON APCH TO HAWTHORNE. HAWTHORNE WAS NOT MADE AWARE OF OUR OP IN THE AREA BY LAX TWR OR MYSELF. THE LACK OF COM BTWN LAX TWR; HAWTHORNE TWR; AND MYSELF WAS MOST LIKELY THE DETERMINING FACTOR. SUPPLEMENTAL INFO FROM ACN 489071: FLYING SBOUND ALONG PASS 3. THE REGION IS AN AREA OF N/S PASSES BTWN THE 110 FREEWAY AND THE 710 FREEWAY; FLOWN AT AN ALT OF 900 FT. THE SOUTHERN BORDER IN THIS AREA RUNS E AND W OVER THE 105 FREEWAY. THE ENTIRE REGION WAS DONE WHILE IN DIRECT COM WITH LAX TWR ON THE HELI FREQ OF 119.8. AT THE SAME TIME COM WAS MAINTAINED WITH THE HELI TFC IN THE AREA ON 123.025. PASS 3 IS JUST TO THE E OF THE 110 FREEWAY. THE NEXT PASS TO BE DONE UPON THE COMPLETION OF 3 WAS 5. THIS IS 1760 FT LATERALLY TO THE E OF PASS 3. THE TURN TO PASS 5 NBOUND REQUIRES A SLIGHT R TURN; THEN A COMPLETE L TURN NBOUND. THIS IS DONE TO ALLOW SUFFICIENT DISTANCE TO MAKE A SAFE TURN FROM PASS 3 TO PASS 5. THE INCIDENT: AFTER COMPLETING PASS 3 OVER THE 105 FREEWAY (SBOUND); THE SLIGHT R TURN WAS INITIATED. AFTER APPROX A TURN OF 30-40 DEGS; AN IMMEDIATE L TURN WAS INITIATED. AS THE ACFT CAME THROUGH A HEADING OF APPROX 160 DEGS TRUE; VISUAL WITH THE KING AIR ON THE LOC TO HAWTHORNE WAS ESTABLISHED. VISUAL WITH THE ACFT WAS ESTABLISHED WITH A HORIZONTAL SEPARATION FROM US AT ABOUT 1/8 MI. IT WAS DETERMINED BY OUR PIC THAT GREATER SEPARATION WOULD BE ESTABLISHED IF THE CURRENT L TURN AT 45 DEGS OF BANK WAS CONTINUED. AT THEIR CLOSEST POINT; THE AIRPLANES WERE VERTICALLY SEPARATED BY APPROX 300 FT. THE TURN NBOUND WAS COMPLETED BY US AND THE KING AIR RESUMED THE APCH. 5 MINS AFTER THE INCIDENT; HAWTHORNE TWR WAS CONTACTED BY OUR PIC. HAWTHORNE TWR GAVE US A PHONE NUMBER TO CALL WHEN WE WERE ON THE GND. AT NO TIME DID HAWTHORNE TWR REQUEST ANY FUTURE RADIO CALLS BY US TO LET THEM KNOW REGION WAS BEING COVERED. RADIO CONTACT WAS MAINTAINED WITH LAX TWR FOR THE REMAINDER OF THE OP IN REGION. CAUSE OF THE PROB: I BELIEVE THE CAUSE OF THE PROB WAS LAX TWR WAS NOT IN BETTER COM WITH HAWTHORNE TWR; WHICH RESULTED IN THAT THEY DID NOT CALL OUT THE TFC TO US. TO PREVENT A RECURRENCE: MAINTAIN CONSTANTLY WITH SOCAL APCH AND NOT WITH LOS ANGELES TWR.