Narrative:

Traffic called by approach control 12 O'clock -- 10500 swbound. No visual contact. TCASII target indicated 12 O'clock, 10700 ft. TCASII resolution to climb displayed. Aircraft climbed to 12000 ft. Aircraft sighted 11:30, approximately 1 mi. Advised ATC and descended back to 11000 ft. TCASII worked as designed. FAA air carrier inspector was on jump seat check riding crew.

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Original NASA ASRS Text

Title: AN ACR LGT CREW CLBED IN RESPONSE TO A TCASII COMMAND. THERE WAS AN ACR INSPECTOR IN THE COCKPIT TO WITNESS THE WHOLE THING.

Narrative: TFC CALLED BY APCH CTL 12 O'CLOCK -- 10500 SWBOUND. NO VISUAL CONTACT. TCASII TARGET INDICATED 12 O'CLOCK, 10700 FT. TCASII RESOLUTION TO CLB DISPLAYED. ACFT CLBED TO 12000 FT. ACFT SIGHTED 11:30, APPROX 1 MI. ADVISED ATC AND DSNDED BACK TO 11000 FT. TCASII WORKED AS DESIGNED. FAA ACR INSPECTOR WAS ON JUMP SEAT CHK RIDING CREW.

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.