Narrative:

We were descending on a visual approach from the northwest, to runway 32, reporting a left midfield downwind to runway 32. The visibility was marginal -- haze and mist. Vertical visibility was good. As we approached the aerodrome, we heard the tower controller giving vector instructions to an inbound cherokee. The cherokee seemed to be familiar with the local airport, had the airport in sight, but couldn't see any other traffic in his vicinity. The tower gave him several vectors in a short amount of time, that must have confused him. He was told to look for a twin cessna (402 type?) and a beech 1900D. He was to be following us, in the beech, to runway 32 -- only he was coming in from the east and on a right downwind to runway 32. We were vigilant for this other aircraft as we turned our left base from 1500 ft AGL, descending. At 1000 ft AGL, I called '1000 ft to the field.' captain then called for 'final landing items.' I proceeded to run the checklist. As the captain turned final, he was looking out the left window at the runway. I looked forward to see the cherokee at 12 O'clock position and the same altitude, coming head-on. I said 'look out,' and I managed to take the controls and bank the aircraft to the right to miss the cherokee. I think he saw us at the same time and banked to his right. The tower had no idea how close we were. I think the tower was frustrated with the lack of visibility and told the cherokee to depart the pattern until he could see the traffic as pointed out by the tower.

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Original NASA ASRS Text

Title: ACR B190 FLC ENTERS L TFC ON VISUAL APCH. TWR TIRES TO SEQUENCE PA28 IN R TFC TO FOLLOW THE B190. THE B190 FO SEES THE PA28 HEAD-ON ON FINAL, OPPOSITE DIRECTION, AND INITIATES EVASIVE ACTION. THE PA28, APPARENTLY CONFUSED AND DISORIENTED, ALSO TAKES EVASIVE ACTION.

Narrative: WE WERE DSNDING ON A VISUAL APCH FROM THE NW, TO RWY 32, RPTING A L MIDFIELD DOWNWIND TO RWY 32. THE VISIBILITY WAS MARGINAL -- HAZE AND MIST. VERT VISIBILITY WAS GOOD. AS WE APCHED THE AERODROME, WE HEARD THE TWR CTLR GIVING VECTOR INSTRUCTIONS TO AN INBOUND CHEROKEE. THE CHEROKEE SEEMED TO BE FAMILIAR WITH THE LCL ARPT, HAD THE ARPT IN SIGHT, BUT COULDN'T SEE ANY OTHER TFC IN HIS VICINITY. THE TWR GAVE HIM SEVERAL VECTORS IN A SHORT AMOUNT OF TIME, THAT MUST HAVE CONFUSED HIM. HE WAS TOLD TO LOOK FOR A TWIN CESSNA (402 TYPE?) AND A BEECH 1900D. HE WAS TO BE FOLLOWING US, IN THE BEECH, TO RWY 32 -- ONLY HE WAS COMING IN FROM THE E AND ON A R DOWNWIND TO RWY 32. WE WERE VIGILANT FOR THIS OTHER ACFT AS WE TURNED OUR L BASE FROM 1500 FT AGL, DSNDING. AT 1000 FT AGL, I CALLED '1000 FT TO THE FIELD.' CAPT THEN CALLED FOR 'FINAL LNDG ITEMS.' I PROCEEDED TO RUN THE CHKLIST. AS THE CAPT TURNED FINAL, HE WAS LOOKING OUT THE L WINDOW AT THE RWY. I LOOKED FORWARD TO SEE THE CHEROKEE AT 12 O'CLOCK POS AND THE SAME ALT, COMING HEAD-ON. I SAID 'LOOK OUT,' AND I MANAGED TO TAKE THE CTLS AND BANK THE ACFT TO THE R TO MISS THE CHEROKEE. I THINK HE SAW US AT THE SAME TIME AND BANKED TO HIS R. THE TWR HAD NO IDEA HOW CLOSE WE WERE. I THINK THE TWR WAS FRUSTRATED WITH THE LACK OF VISIBILITY AND TOLD THE CHEROKEE TO DEPART THE PATTERN UNTIL HE COULD SEE THE TFC AS POINTED OUT BY THE TWR.

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.