Narrative:

While cruising at 17500 ft VFR, with radar advisories from ZNY, we were advised of a jet climbing through our altitude. The controller asked if we had visual contact with the traffic which we did not. Within a short period the controller advised us to turn 30 degrees right to avoid the traffic. As we entered a turn we received a TA which immediately changed into an RA climb. We then received an 'increase vertical speed' command, which caused us to climb through FL180. At FL182 we obtained visual contact with the traffic and stopped the climb at FL183. We then descended back down to 17500 ft. The controller asked our altitude and advised us that VFR was not allowed above FL180. We told him that we understood that, but had to follow the RA climb. Supplemental information from acn 446473: controller also stated that midway had executed a climb in response to an RA. Both aircraft should not have been told to climb by TCASII.

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Original NASA ASRS Text

Title: FA20 HAS NMAC IN ATC DIRECTED TURN AND CLBS THROUGH FL183 DURING RESOLUTION NEAR LHY.

Narrative: WHILE CRUISING AT 17500 FT VFR, WITH RADAR ADVISORIES FROM ZNY, WE WERE ADVISED OF A JET CLBING THROUGH OUR ALT. THE CTLR ASKED IF WE HAD VISUAL CONTACT WITH THE TFC WHICH WE DID NOT. WITHIN A SHORT PERIOD THE CTLR ADVISED US TO TURN 30 DEGS R TO AVOID THE TFC. AS WE ENTERED A TURN WE RECEIVED A TA WHICH IMMEDIATELY CHANGED INTO AN RA CLB. WE THEN RECEIVED AN 'INCREASE VERT SPD' COMMAND, WHICH CAUSED US TO CLB THROUGH FL180. AT FL182 WE OBTAINED VISUAL CONTACT WITH THE TFC AND STOPPED THE CLB AT FL183. WE THEN DSNDED BACK DOWN TO 17500 FT. THE CTLR ASKED OUR ALT AND ADVISED US THAT VFR WAS NOT ALLOWED ABOVE FL180. WE TOLD HIM THAT WE UNDERSTOOD THAT, BUT HAD TO FOLLOW THE RA CLB. SUPPLEMENTAL INFO FROM ACN 446473: CTLR ALSO STATED THAT MIDWAY HAD EXECUTED A CLB IN RESPONSE TO AN RA. BOTH ACFT SHOULD NOT HAVE BEEN TOLD TO CLB BY TCASII.

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.