Narrative:

The flight departed from set, st charles county airport, to cps, parks downtown airport. The flight progressed normally and at 8 NM northwest of cps, I contacted tower and was told to proceed. I soon began to see traffic departing and arriving to the airport. At this time I saw traffic at my 1 O'clock position and about 1 mi. The traffic was at a higher altitude than me and seemed to be traveling slower. Tower contacted me and told me to follow behind the traffic. I requested that I be allowed to pass to the left of the traffic. Tower cleared me to pass parallel the traffic. A moment later I was ahead of the traffic and still at a lower altitude. The traffic began to accelerate and began a slow turn to the left. I maintained my current heading. As the traffic descended and accelerated, I determined that they must not have seen me. I began retarding the throttle to allow the traffic to pass. A moment later they seemed to make a harder left bank and descended into my flight path. I pushed the yoke forward and began a left bank and retarded the throttle. Tower told the traffic to widen to the right and cleared them to land on runway 4. I leveled off and entered a left downwind for runway 30L and tower cleared me to land. Problems: 1) I believe there was a miscom of who was supposed to be in front after I was cleared to pass. I should have requested clarification once I noticed the traffic turning towards me. 2) from my perspective, there was a situational awareness problem with the pilots of the other aircraft.

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Original NASA ASRS Text

Title: A PLT HAS TO TURN TO AVOID ANOTHER ACFT WHILE LNDG AT CPS.

Narrative: THE FLT DEPARTED FROM SET, ST CHARLES COUNTY ARPT, TO CPS, PARKS DOWNTOWN ARPT. THE FLT PROGRESSED NORMALLY AND AT 8 NM NW OF CPS, I CONTACTED TWR AND WAS TOLD TO PROCEED. I SOON BEGAN TO SEE TFC DEPARTING AND ARRIVING TO THE ARPT. AT THIS TIME I SAW TFC AT MY 1 O'CLOCK POS AND ABOUT 1 MI. THE TFC WAS AT A HIGHER ALT THAN ME AND SEEMED TO BE TRAVELING SLOWER. TWR CONTACTED ME AND TOLD ME TO FOLLOW BEHIND THE TFC. I REQUESTED THAT I BE ALLOWED TO PASS TO THE L OF THE TFC. TWR CLRED ME TO PASS PARALLEL THE TFC. A MOMENT LATER I WAS AHEAD OF THE TFC AND STILL AT A LOWER ALT. THE TFC BEGAN TO ACCELERATE AND BEGAN A SLOW TURN TO THE L. I MAINTAINED MY CURRENT HDG. AS THE TFC DSNDED AND ACCELERATED, I DETERMINED THAT THEY MUST NOT HAVE SEEN ME. I BEGAN RETARDING THE THROTTLE TO ALLOW THE TFC TO PASS. A MOMENT LATER THEY SEEMED TO MAKE A HARDER L BANK AND DSNDED INTO MY FLT PATH. I PUSHED THE YOKE FORWARD AND BEGAN A L BANK AND RETARDED THE THROTTLE. TWR TOLD THE TFC TO WIDEN TO THE R AND CLRED THEM TO LAND ON RWY 4. I LEVELED OFF AND ENTERED A L DOWNWIND FOR RWY 30L AND TWR CLRED ME TO LAND. PROBS: 1) I BELIEVE THERE WAS A MISCOM OF WHO WAS SUPPOSED TO BE IN FRONT AFTER I WAS CLRED TO PASS. I SHOULD HAVE REQUESTED CLARIFICATION ONCE I NOTICED THE TFC TURNING TOWARDS ME. 2) FROM MY PERSPECTIVE, THERE WAS A SITUATIONAL AWARENESS PROB WITH THE PLTS OF THE OTHER ACFT.

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.