Narrative:

Level at FL240 in cruise. Received TCASII RA that directed a climb at 2000 FPM. Conflicting traffic was indicating on TCASII at a position of 11 O'clock climbing through FL215. We responded to the RA as directed, resulting in a climb to FL250 before TCASII indicated clear of traffic. We notified ATC of the altitude deviation and descended back to FL240. The traffic was never acquired visually. Supplemental information from acn 363560: other aircraft appeared (on TCASII) to level off at FL230. We notified ATC of our climb and our intention to descend back to FL240, which we did when TCASII indicated we were clear of traffic. ATC only said 'roger' with no traffic information.

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Original NASA ASRS Text

Title: PIC OF ACR MLG LEAVES FL240 FOR FL250 WHEN RECEIVING TCASII RA OF CLBING TFC BELOW THEM. NO LOSS OF SEPARATION.

Narrative: LEVEL AT FL240 IN CRUISE. RECEIVED TCASII RA THAT DIRECTED A CLB AT 2000 FPM. CONFLICTING TFC WAS INDICATING ON TCASII AT A POS OF 11 O'CLOCK CLBING THROUGH FL215. WE RESPONDED TO THE RA AS DIRECTED, RESULTING IN A CLB TO FL250 BEFORE TCASII INDICATED CLR OF TFC. WE NOTIFIED ATC OF THE ALTDEV AND DSNDED BACK TO FL240. THE TFC WAS NEVER ACQUIRED VISUALLY. SUPPLEMENTAL INFO FROM ACN 363560: OTHER ACFT APPEARED (ON TCASII) TO LEVEL OFF AT FL230. WE NOTIFIED ATC OF OUR CLB AND OUR INTENTION TO DSND BACK TO FL240, WHICH WE DID WHEN TCASII INDICATED WE WERE CLR OF TFC. ATC ONLY SAID 'ROGER' WITH NO TFC INFO.

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.