Narrative:

We were departing in a C206 VFR without a flight plan. Approach gave us radar services and a transponder code. After the initial climb; I asked ATC for higher to get us out of some haze that was obscuring visibility to around 4 to 5 miles. ATC cleared us to maintain at or below 5;500. We climbed to 5;500. After about 5 minutes; the controllers had switched. About 2 minutes after that; the new controller told a citation to descend and maintain 4;000. Within 10 seconds of that instruction; my passenger and I saw the citation at our 1 o clock; merging; about 300 feet higher and descending towards our path. The citation told ATC he got a TCAS RA and began to climb and turn to the left to avoid us. I disconnected our autopilot and initiated a descent. I only descended about 20 feet before the citation passed our 3 o'clock high. At the closest point I would estimate the citation was about 400 feet right of us and 300 feet high. Less than 10 seconds had passed by the time we saw the conflict and the citation had passed us. I believe a classic chain of events led to this. First; the visibility was poor in the haze. Second; the controllers had switched not long before. Traffic was not heavy at the time; and I don't believe the controller was overwhelmed. However; the controller failed to give the citation an alert about us and vice versa. I think the citation's TCAS RA broke the chain of events. Had he not acted quickly on it; I don't believe we would have collided; but it would have certainly been much; much closer. I'm not a controller and certainly not an expert on their job; but I believe during the controller swap and brief our aircraft wasn't mentioned and we were forgot about until the TCAS RA.

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Original NASA ASRS Text

Title: C206 pilot on a VFR departure in hazy conditions reported a NMAC with a Citation descending on a converging course.

Narrative: We were departing in a C206 VFR without a flight plan. Approach gave us radar services and a transponder code. After the initial climb; I asked ATC for higher to get us out of some haze that was obscuring visibility to around 4 to 5 miles. ATC cleared us to maintain at or below 5;500. We climbed to 5;500. After about 5 minutes; the Controllers had switched. About 2 minutes after that; the new Controller told a Citation to descend and maintain 4;000. Within 10 seconds of that instruction; my passenger and I saw the Citation at our 1 o clock; merging; about 300 feet higher and descending towards our path. The Citation told ATC he got a TCAS RA and began to climb and turn to the left to avoid us. I disconnected our autopilot and initiated a descent. I only descended about 20 feet before the Citation passed our 3 o'clock high. At the closest point I would estimate the Citation was about 400 feet right of us and 300 feet high. Less than 10 seconds had passed by the time we saw the conflict and the Citation had passed us. I believe a classic chain of events led to this. First; the visibility was poor in the haze. Second; the Controllers had switched not long before. Traffic was not heavy at the time; and I don't believe the Controller was overwhelmed. However; the Controller failed to give the Citation an alert about us and vice versa. I think the Citation's TCAS RA broke the chain of events. Had he not acted quickly on it; I don't believe we would have collided; but it would have certainly been much; much closer. I'm not a Controller and certainly not an expert on their job; but I believe during the Controller swap and brief our aircraft wasn't mentioned and we were forgot about until the TCAS RA.

Data retrieved from NASA's ASRS site 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.