Narrative:

TCASII issued an RA to descend. We descended to FL252 and informed the controller. Traffic was spotted about 30 seconds later at our 3 O'clock at 3 mi and 1000 ft above us. After clearing, we climbed to FL260. It appeared the TCASII was too sensitive and should not have issued the RA.

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Original NASA ASRS Text

Title: ACR FLC DEVIATED FROM THEIR ASSIGNED ALT IN RESPONSE TO THE ACFT'S TCASII ALERT WARNING.

Narrative: TCASII ISSUED AN RA TO DSND. WE DSNDED TO FL252 AND INFORMED THE CTLR. TFC WAS SPOTTED ABOUT 30 SECONDS LATER AT OUR 3 O'CLOCK AT 3 MI AND 1000 FT ABOVE US. AFTER CLRING, WE CLBED TO FL260. IT APPEARED THE TCASII WAS TOO SENSITIVE AND SHOULD NOT HAVE ISSUED THE RA.

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.