Narrative:

TCASII RA indicated target at 12 O'clock closing fast. Initiated 1500 FPM climb for approximately 600 ft at which time target passed beneath us. Immediately notified center and returned to fl. Center advised that traffic was at assigned altitude and there was 2000 ft separation. Supplemental information from acn 197743: in cruise at FL350. Center gave TA 12 O'clock, 20 mi, FL330. Shortly after, received TCASII alert to climb 2000 FPM. Target 1 O'clock, 4 mi, 1900 ft low. After establishing climb received 'monitor vertical velocity' deviation was to FL360. Received 'clear of traffic' advised center and descended to 350. Questioned center about traffic and was told traffic had been level at FL330 entire time.

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Original NASA ASRS Text

Title: ACR RESPONDS TO TCASII RA. CLBS.

Narrative: TCASII RA INDICATED TARGET AT 12 O'CLOCK CLOSING FAST. INITIATED 1500 FPM CLB FOR APPROX 600 FT AT WHICH TIME TARGET PASSED BENEATH US. IMMEDIATELY NOTIFIED CENTER AND RETURNED TO FL. CENTER ADVISED THAT TFC WAS AT ASSIGNED ALT AND THERE WAS 2000 FT SEPARATION. SUPPLEMENTAL INFO FROM ACN 197743: IN CRUISE AT FL350. CENTER GAVE TA 12 O'CLOCK, 20 MI, FL330. SHORTLY AFTER, RECEIVED TCASII ALERT TO CLB 2000 FPM. TARGET 1 O'CLOCK, 4 MI, 1900 FT LOW. AFTER ESTABLISHING CLB RECEIVED 'MONITOR VERT VELOCITY' DEV WAS TO FL360. RECEIVED 'CLR OF TFC' ADVISED CENTER AND DSNDED TO 350. QUESTIONED CENTER ABOUT TFC AND WAS TOLD TFC HAD BEEN LEVEL AT FL330 ENTIRE TIME.

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.