Narrative:

We were descending on br-54V. I was copilot, sitting in right seat. Captain noticed TCASII traffic at 7700 ft MSL, closing approximately 15 mi away heading for freeport, bahamas. We were descending towards palm beach. Captain had aircraft on autoplt on a shallow descent 800 FPM. Target closed rapidly, ATC alerted us at 3 mi away at the same time as our TCASII alerted. Captain remained on autoplt until traffic closed within a mi or so. Aircraft was disengaged from autoplt and banked to right, away from traffic, still descending at shallow angle. When wings came level, I spotted traffic merging with us and replied 'there he is, dive it, dive it.' I placed my hands on the yoke and roughly doubled or tripled descent rate. Traffic passed directly overhead. I felt it was necessary due to the PIC not seeing the traffic and/or lack of action. Captain/PIC then leveled aircraft at 4000 ft and rejoined 54V-br radial. Traffic took no evasive action. How problem arose: VFR traffic not using flight following. ATC having heavy workload and not advising suggested course of action. PF not increasing descent rate 10 mi away. PNF not being vocal enough in suggesting possible actions. How discovered: ATC, tcasi, visual. Judgement: major factor. Factors affecting: too much faith in ATC suggesting action, it didn't happen, he was far too busy.

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Original NASA ASRS Text

Title: BEECH 1900 DSNDING HAS NMAC WITH A C402 COMING FROM THE OPPOSITE DIRECTION IN CRUISE FLT AFTER ATC TA, TCASII ALERT AND VISUAL SIGHTING BY THE PNF FO.

Narrative: WE WERE DSNDING ON BR-54V. I WAS COPLT, SITTING IN R SEAT. CAPT NOTICED TCASII TFC AT 7700 FT MSL, CLOSING APPROX 15 MI AWAY HEADING FOR FREEPORT, BAHAMAS. WE WERE DSNDING TOWARDS PALM BEACH. CAPT HAD ACFT ON AUTOPLT ON A SHALLOW DSCNT 800 FPM. TARGET CLOSED RAPIDLY, ATC ALERTED US AT 3 MI AWAY AT THE SAME TIME AS OUR TCASII ALERTED. CAPT REMAINED ON AUTOPLT UNTIL TFC CLOSED WITHIN A MI OR SO. ACFT WAS DISENGAGED FROM AUTOPLT AND BANKED TO R, AWAY FROM TFC, STILL DSNDING AT SHALLOW ANGLE. WHEN WINGS CAME LEVEL, I SPOTTED TFC MERGING WITH US AND REPLIED 'THERE HE IS, DIVE IT, DIVE IT.' I PLACED MY HANDS ON THE YOKE AND ROUGHLY DOUBLED OR TRIPLED DSCNT RATE. TFC PASSED DIRECTLY OVERHEAD. I FELT IT WAS NECESSARY DUE TO THE PIC NOT SEEING THE TFC AND/OR LACK OF ACTION. CAPT/PIC THEN LEVELED ACFT AT 4000 FT AND REJOINED 54V-BR RADIAL. TFC TOOK NO EVASIVE ACTION. HOW PROB AROSE: VFR TFC NOT USING FLT FOLLOWING. ATC HAVING HVY WORKLOAD AND NOT ADVISING SUGGESTED COURSE OF ACTION. PF NOT INCREASING DSCNT RATE 10 MI AWAY. PNF NOT BEING VOCAL ENOUGH IN SUGGESTING POSSIBLE ACTIONS. HOW DISCOVERED: ATC, TCASI, VISUAL. JUDGEMENT: MAJOR FACTOR. FACTORS AFFECTING: TOO MUCH FAITH IN ATC SUGGESTING ACTION, IT DIDN'T HAPPEN, HE WAS FAR TOO BUSY.

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.