Narrative:

Climbing west out of bos cleared to 16000 ft. When we leveled at 16000 ft, center said we had traffic at 11 O'clock position, 4 mi at 17000 ft. Asked if we had traffic, we said yes. ATC cleared us to climb VFR to FL220. I started to climb then noticed the traffic was not moving in my windshield, I pitched up to 12 degrees. The traffic passed on my left side below me in a right turn. At the time of passage I looked at my altimeter, it was rapidly going through 18200 ft. Traffic said they had to take immediate action to avoid us. I suggest that all transport category aircraft be equipped with TCASII, that would give the pilots more information. Supplemental information from acn 388810: ATC called traffic at 11 O'clock position and 17000 ft. The traffic was an air carrier saab 340 and we were given a climb through his altitude and told to maintain visual. We expedited a climb maintaining visual at all times but the air carrier saab 340 felt we were too close and made a right turn stating that he received a TCASII warning. There was no incident and we had the saab 340 traffic in our sight at all times.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR GAVE AN ACR LGT TFC INFO ON AN ACR SF340 AND WHEN TFC SIGHTED CLRED THE LGT TO CLB VFR THROUGH THE SF340'S ALT. THE LGT EXPEDITED HIS CLB, BUT THE SF340 MADE AN EVASIVE ACTION TURN AS HE FELT THE LGT WAS TOO CLOSE.

Narrative: CLBING W OUT OF BOS CLRED TO 16000 FT. WHEN WE LEVELED AT 16000 FT, CTR SAID WE HAD TFC AT 11 O'CLOCK POS, 4 MI AT 17000 FT. ASKED IF WE HAD TFC, WE SAID YES. ATC CLRED US TO CLB VFR TO FL220. I STARTED TO CLB THEN NOTICED THE TFC WAS NOT MOVING IN MY WINDSHIELD, I PITCHED UP TO 12 DEGS. THE TFC PASSED ON MY L SIDE BELOW ME IN A R TURN. AT THE TIME OF PASSAGE I LOOKED AT MY ALTIMETER, IT WAS RAPIDLY GOING THROUGH 18200 FT. TFC SAID THEY HAD TO TAKE IMMEDIATE ACTION TO AVOID US. I SUGGEST THAT ALL TRANSPORT CATEGORY ACFT BE EQUIPPED WITH TCASII, THAT WOULD GIVE THE PLTS MORE INFO. SUPPLEMENTAL INFO FROM ACN 388810: ATC CALLED TFC AT 11 O'CLOCK POS AND 17000 FT. THE TFC WAS AN ACR SAAB 340 AND WE WERE GIVEN A CLB THROUGH HIS ALT AND TOLD TO MAINTAIN VISUAL. WE EXPEDITED A CLB MAINTAINING VISUAL AT ALL TIMES BUT THE ACR SAAB 340 FELT WE WERE TOO CLOSE AND MADE A R TURN STATING THAT HE RECEIVED A TCASII WARNING. THERE WAS NO INCIDENT AND WE HAD THE SAAB 340 TFC IN OUR SIGHT AT ALL TIMES.

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.