Narrative:

Cleared for visual approach at orf, switch to tower and cleared to land at 1000 ft full landing confign. Tcasi goes off 'traffic.' we look and see nothing. Tcasi indicate possibly behind us. Navy ship set this off about 50% of the time I land orf. We finally pick up a cessna at 12 O'clock position, landing also it appears. We apply go around procedures and bank left and climb, do a left downwind and are cleared to land again. The cessna should not have been in our airspace as we were cleared the approach and cleared to land.

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Original NASA ASRS Text

Title: COMMUTER LTT HAS NMAC WITH SMA CESSNA ON VISUAL APCH. TCASI GAVE ALERT. FLC EXECUTED A GAR.

Narrative: CLRED FOR VISUAL APCH AT ORF, SWITCH TO TWR AND CLRED TO LAND AT 1000 FT FULL LNDG CONFIGN. TCASI GOES OFF 'TFC.' WE LOOK AND SEE NOTHING. TCASI INDICATE POSSIBLY BEHIND US. NAVY SHIP SET THIS OFF ABOUT 50% OF THE TIME I LAND ORF. WE FINALLY PICK UP A CESSNA AT 12 O'CLOCK POS, LNDG ALSO IT APPEARS. WE APPLY GAR PROCS AND BANK L AND CLB, DO A L DOWNWIND AND ARE CLRED TO LAND AGAIN. THE CESSNA SHOULD NOT HAVE BEEN IN OUR AIRSPACE AS WE WERE CLRED THE APCH AND CLRED TO LAND.

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.