Narrative:

While in IMC, cruise, autoplt and altitude hold engaged at FL290, TCASII gave a TA immediately followed by 'climb' command. The captain responded immediately by disengaging the autoplt and initiating a climb. I notified ATC of TCASII RA and of our vacating FL290 in a climb. The captain climbed to FL295, the TCASII RA then disappeared. ZJX responded that there was traffic nearby at FL280. ZJX then descended us to FL290 where we continued the flight without incident.

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Original NASA ASRS Text

Title: B767 FLC CLB OFF FL290 CRUISE ALT IN RESPONSE TO TCASII RA.

Narrative: WHILE IN IMC, CRUISE, AUTOPLT AND ALT HOLD ENGAGED AT FL290, TCASII GAVE A TA IMMEDIATELY FOLLOWED BY 'CLB' COMMAND. THE CAPT RESPONDED IMMEDIATELY BY DISENGAGING THE AUTOPLT AND INITIATING A CLB. I NOTIFIED ATC OF TCASII RA AND OF OUR VACATING FL290 IN A CLB. THE CAPT CLBED TO FL295, THE TCASII RA THEN DISAPPEARED. ZJX RESPONDED THAT THERE WAS TFC NEARBY AT FL280. ZJX THEN DSNDED US TO FL290 WHERE WE CONTINUED THE FLT WITHOUT INCIDENT.

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.