Narrative:

Several aircraft were in the landing pattern at 5c1. 1 airplane landed before my airplane and turned around at the end of the runway to back taxi (the exit at the end of that runway was closed). I reported base entry on the radio frequency for the airport and then reported final turn. The airplane that landed had not vacated the runway. I heard an experimental state that he was taxiing onto the runway and I saw him on the overrun. I announced a go around low pass only so the other aircraft could back-taxi and clear the runway. I added power and flew parallel to the runway but on the right of the centerline. At approximately midfield I observed the experimental below me and in front of my left wing. He had proceeded with his takeoff and was climbing. I made an immediate right turn and entered the pattern on downwind and subsequently landed. The pilot of the experimental did not announce his takeoff, only his taxi onto the active runway. His judgement in proceeding with his takeoff in conjunction with my go around was also a factor.

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Original NASA ASRS Text

Title: PA28 PLT HAS NMAC WITH EXPERIMENTAL ACFT WHICH DEPARTS WHEN RPTR ACFT ON FINAL. GAR IS EXECUTED.

Narrative: SEVERAL ACFT WERE IN THE LNDG PATTERN AT 5C1. 1 AIRPLANE LANDED BEFORE MY AIRPLANE AND TURNED AROUND AT THE END OF THE RWY TO BACK TAXI (THE EXIT AT THE END OF THAT RWY WAS CLOSED). I RPTED BASE ENTRY ON THE RADIO FREQ FOR THE ARPT AND THEN RPTED FINAL TURN. THE AIRPLANE THAT LANDED HAD NOT VACATED THE RWY. I HEARD AN EXPERIMENTAL STATE THAT HE WAS TAXIING ONTO THE RWY AND I SAW HIM ON THE OVERRUN. I ANNOUNCED A GAR LOW PASS ONLY SO THE OTHER ACFT COULD BACK-TAXI AND CLR THE RWY. I ADDED PWR AND FLEW PARALLEL TO THE RWY BUT ON THE R OF THE CTRLINE. AT APPROX MIDFIELD I OBSERVED THE EXPERIMENTAL BELOW ME AND IN FRONT OF MY L WING. HE HAD PROCEEDED WITH HIS TKOF AND WAS CLBING. I MADE AN IMMEDIATE R TURN AND ENTERED THE PATTERN ON DOWNWIND AND SUBSEQUENTLY LANDED. THE PLT OF THE EXPERIMENTAL DID NOT ANNOUNCE HIS TKOF, ONLY HIS TAXI ONTO THE ACTIVE RWY. HIS JUDGEMENT IN PROCEEDING WITH HIS TKOF IN CONJUNCTION WITH MY GAR WAS ALSO A FACTOR.

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.