Narrative:

After departing syr I cancelled IFR and went VFR direct to lga (our schedules are impossible to maintain if one flies IFR prescribed routes). I told first officer to intercept hudson southbound. We were getting advisories the entire flight with handoffs, then center handed us off to approach. Approach cancelled us and suggested north.Y. Approach on 126.80. I called 4 times and didn't even get a 'stand by,' or too 'busy for VFR,' so I called north.Y. On 120.80 and then gave me a code. I had advised them 'now 35 DME north lga, heading south following hudson river, request TCA clearance and advisories at 2000' MSL.' they replied, 'maintain 3000, proceed to tappan zee bridge at 24.5 DME.' 4.5 DME from TCA I advised approach, 'we need 2900' or TCA clearance.' they replied,' cleared into TCA at 3000'.' all along we had been given traffic advisories by this controller. While giving passenger briefing, out of corner of my eye while scanning, I saw traffic. I stopped brief, grabbed yoke and banked 30+ degrees to avoid traffic. Traffic never got closer then 1000-2000', but had we not seen it, we would have felt more than propeller wash. ATC apologized. Passenger asked what had happened. Good practice to scan, assistant chief pilot advised I should fly fir, but when IFR and VMC, it is still pilot's responsibility to scan and avoid traffic per far 91.67. We were in TCA by 2.3 mi. I don't know if ATC was talking to the single engine, or if he was below floor or thought he was.

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Original NASA ASRS Text

Title: FLT CREW OF SMT ON VFR PLAN WITH RADAR SURVEILLANCE TOOK EVASIVE ACTION TO AVOID AN NMAC AT 3000' MSL IN LGA TCA.

Narrative: AFTER DEPARTING SYR I CANCELLED IFR AND WENT VFR DIRECT TO LGA (OUR SCHEDULES ARE IMPOSSIBLE TO MAINTAIN IF ONE FLIES IFR PRESCRIBED ROUTES). I TOLD F/O TO INTERCEPT HUDSON SBND. WE WERE GETTING ADVISORIES THE ENTIRE FLT WITH HDOFS, THEN CENTER HANDED US OFF TO APCH. APCH CANCELLED US AND SUGGESTED N.Y. APCH ON 126.80. I CALLED 4 TIMES AND DIDN'T EVEN GET A 'STAND BY,' OR TOO 'BUSY FOR VFR,' SO I CALLED N.Y. ON 120.80 AND THEN GAVE ME A CODE. I HAD ADVISED THEM 'NOW 35 DME N LGA, HDG S FOLLOWING HUDSON RIVER, REQUEST TCA CLRNC AND ADVISORIES AT 2000' MSL.' THEY REPLIED, 'MAINTAIN 3000, PROCEED TO TAPPAN ZEE BRIDGE AT 24.5 DME.' 4.5 DME FROM TCA I ADVISED APCH, 'WE NEED 2900' OR TCA CLRNC.' THEY REPLIED,' CLRED INTO TCA AT 3000'.' ALL ALONG WE HAD BEEN GIVEN TFC ADVISORIES BY THIS CTLR. WHILE GIVING PAX BRIEFING, OUT OF CORNER OF MY EYE WHILE SCANNING, I SAW TFC. I STOPPED BRIEF, GRABBED YOKE AND BANKED 30+ DEGS TO AVOID TFC. TFC NEVER GOT CLOSER THEN 1000-2000', BUT HAD WE NOT SEEN IT, WE WOULD HAVE FELT MORE THAN PROP WASH. ATC APOLOGIZED. PAX ASKED WHAT HAD HAPPENED. GOOD PRACTICE TO SCAN, ASSISTANT CHIEF PLT ADVISED I SHOULD FLY FIR, BUT WHEN IFR AND VMC, IT IS STILL PLT'S RESPONSIBILITY TO SCAN AND AVOID TFC PER FAR 91.67. WE WERE IN TCA BY 2.3 MI. I DON'T KNOW IF ATC WAS TALKING TO THE SINGLE ENG, OR IF HE WAS BELOW FLOOR OR THOUGHT HE WAS.

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.