Narrative:

We were cleared to climb to FL230. Passing FL220, TCASII issued a TA. Aircraft was spotted and confirmed to be level at FL240. As VNAV leveled aircraft at FL230, TCASII gave an RA to descend at 1500 FPM or greater. Other aircraft was still at FL240 and in visual sight so we did not descend and stayed level at FL230.

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Original NASA ASRS Text

Title: AN ACR B737-400 FLC RPT THAT THEIR TCASII SIGNALED AN RA EVEN THOUGH THEY WERE LEVELING 1000 FT BELOW SIGHTED TFC.

Narrative: WE WERE CLRED TO CLB TO FL230. PASSING FL220, TCASII ISSUED A TA. ACFT WAS SPOTTED AND CONFIRMED TO BE LEVEL AT FL240. AS VNAV LEVELED ACFT AT FL230, TCASII GAVE AN RA TO DSND AT 1500 FPM OR GREATER. OTHER ACFT WAS STILL AT FL240 AND IN VISUAL SIGHT SO WE DID NOT DSND AND STAYED LEVEL AT FL230.

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.