Narrative:

Air carrier X had just entered a left downwind for runway 17 at cos after being cleared for visibility approach. As I rolled out on a 350 degree heading the captain took control of the aircraft, exclaiming, 'I've got the airplane.' I looked out the window and saw a white small aircraft Y with blue stripes conducting a steep left hand descending turn trying to get out of our way. The captain had immediately placed air carrier X in a steep left turn to avoid the oncoming traffic. After landing the captain talked to the control tower supervisor and found that small aircraft Y was receiving flight following from approach control and had not been told of our presences in the pattern. We had not been told to look for traffic either. The FAA said we passed each other with 1/4 mi horizontal and 100' vertical sep.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION WITH SMA IN ARSA. SYSTEM ERROR.

Narrative: ACR X HAD JUST ENTERED A L DOWNWIND FOR RWY 17 AT COS AFTER BEING CLRED FOR VIS APCH. AS I ROLLED OUT ON A 350 DEG HDG THE CAPT TOOK CTL OF THE ACFT, EXCLAIMING, 'I'VE GOT THE AIRPLANE.' I LOOKED OUT THE WINDOW AND SAW A WHITE SMA Y WITH BLUE STRIPES CONDUCTING A STEEP L HAND DSNDING TURN TRYING TO GET OUT OF OUR WAY. THE CAPT HAD IMMEDIATELY PLACED ACR X IN A STEEP L TURN TO AVOID THE ONCOMING TFC. AFTER LNDG THE CAPT TALKED TO THE CTL TWR SUPVR AND FOUND THAT SMA Y WAS RECEIVING FLT FOLLOWING FROM APCH CTL AND HAD NOT BEEN TOLD OF OUR PRESENCES IN THE PATTERN. WE HAD NOT BEEN TOLD TO LOOK FOR TFC EITHER. THE FAA SAID WE PASSED EACH OTHER WITH 1/4 MI HORIZ AND 100' VERT SEP.

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.