Narrative:

We were climbing through approximately 2700 ft MSL, in a right turn to downwind. We were operating VFR, maintaining clear of the san class B airspace to the north and the mexico border to the south. Brown tower handed us off to socal approach, and when the copilot checked in, they called king air traffic. I do not remember where the traffic was called, but I remember the copilot respond that we were 'searching for traffic.' we never did see the traffic, and thought nothing of it. After the air drop, approximately 30 mins later, socal asked us to call the supervisor after landing, regarding the king air traffic. The controller added that he thought we should be ok because we were operating VFR and did not enter class B airspace. The supervisor informed us that the king air had to alter his descent to avoid us, and that we came within 100 ft of each other. Even though we were under a very high workload, I don't think that contributed to the incident. It happened right as we were handed off, and by the sound of it, even if we had seen the king air, we may still have been close to it. If tower had known about the traffic, we could have been looking earlier, and avoided his known track. The best way to prevent this would have been TCASII. Supplemental information from acn 466698: if socal had not asked us to call them we never would have known we came close to traffic. The king air pilot said he had to make evasive maneuvering to avoid a midair collision. We were in communication with socal and monitoring brown tower. No TA's/traffic alerts were given to us that conveyed a sense of urgency. Factors that could attribute to this are a lack of radar coverage/control near sdm, high crew workload, crew fatigue, physical constraints (both pilots wearing helmets), extremely high traffic volume, departing into setting sun, small airspace to work in.

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Original NASA ASRS Text

Title: MIL ACFT IS INFORMED 30 MINS AFTER IT HAPPENED THAT THEY WERE INVOLVED IN AN NMAC WITH A GA ACFT NEAR SDM ARPT, CA.

Narrative: WE WERE CLBING THROUGH APPROX 2700 FT MSL, IN A R TURN TO DOWNWIND. WE WERE OPERATING VFR, MAINTAINING CLR OF THE SAN CLASS B AIRSPACE TO THE N AND THE MEXICO BORDER TO THE S. BROWN TWR HANDED US OFF TO SOCAL APCH, AND WHEN THE COPLT CHKED IN, THEY CALLED KING AIR TFC. I DO NOT REMEMBER WHERE THE TFC WAS CALLED, BUT I REMEMBER THE COPLT RESPOND THAT WE WERE 'SEARCHING FOR TFC.' WE NEVER DID SEE THE TFC, AND THOUGHT NOTHING OF IT. AFTER THE AIR DROP, APPROX 30 MINS LATER, SOCAL ASKED US TO CALL THE SUPVR AFTER LNDG, REGARDING THE KING AIR TFC. THE CTLR ADDED THAT HE THOUGHT WE SHOULD BE OK BECAUSE WE WERE OPERATING VFR AND DID NOT ENTER CLASS B AIRSPACE. THE SUPVR INFORMED US THAT THE KING AIR HAD TO ALTER HIS DSCNT TO AVOID US, AND THAT WE CAME WITHIN 100 FT OF EACH OTHER. EVEN THOUGH WE WERE UNDER A VERY HIGH WORKLOAD, I DON'T THINK THAT CONTRIBUTED TO THE INCIDENT. IT HAPPENED RIGHT AS WE WERE HANDED OFF, AND BY THE SOUND OF IT, EVEN IF WE HAD SEEN THE KING AIR, WE MAY STILL HAVE BEEN CLOSE TO IT. IF TWR HAD KNOWN ABOUT THE TFC, WE COULD HAVE BEEN LOOKING EARLIER, AND AVOIDED HIS KNOWN TRACK. THE BEST WAY TO PREVENT THIS WOULD HAVE BEEN TCASII. SUPPLEMENTAL INFO FROM ACN 466698: IF SOCAL HAD NOT ASKED US TO CALL THEM WE NEVER WOULD HAVE KNOWN WE CAME CLOSE TO TFC. THE KING AIR PLT SAID HE HAD TO MAKE EVASIVE MANEUVERING TO AVOID A MIDAIR COLLISION. WE WERE IN COM WITH SOCAL AND MONITORING BROWN TWR. NO TA'S/TFC ALERTS WERE GIVEN TO US THAT CONVEYED A SENSE OF URGENCY. FACTORS THAT COULD ATTRIBUTE TO THIS ARE A LACK OF RADAR COVERAGE/CTL NEAR SDM, HIGH CREW WORKLOAD, CREW FATIGUE, PHYSICAL CONSTRAINTS (BOTH PLTS WEARING HELMETS), EXTREMELY HIGH TFC VOLUME, DEPARTING INTO SETTING SUN, SMALL AIRSPACE TO WORK IN.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.