Narrative:

We were in level flight at 23000'. West/O receiving a primary target or a TA first, we got an RA at 10:30, 10 mi. The target information was 900' climbing. We did not see the traffic visually and performed the TCAS maneuver, which brought us to 23800' before 'clear of conflict.' we advised ATC and descended back to 23000'. ATC later told us that the traffic had been climbing to 22000'. Interpretation: RA not necessary.

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Original NASA ASRS Text

Title: ACR MLG ALT DEVIATION EXCURSION FOR CLRNC ALT IN RESPONSE TO TCASII RA.

Narrative: WE WERE IN LEVEL FLT AT 23000'. W/O RECEIVING A PRIMARY TARGET OR A TA FIRST, WE GOT AN RA AT 10:30, 10 MI. THE TARGET INFO WAS 900' CLBING. WE DID NOT SEE THE TFC VISUALLY AND PERFORMED THE TCAS MANEUVER, WHICH BROUGHT US TO 23800' BEFORE 'CLR OF CONFLICT.' WE ADVISED ATC AND DSNDED BACK TO 23000'. ATC LATER TOLD US THAT THE TFC HAD BEEN CLBING TO 22000'. INTERP: RA NOT NECESSARY.

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.