Narrative:

An large transport aircraft had landed and I was holding at runway 12 hold line for wake turbulence to clear. An small aircraft Y reported final for 21. I made a remark to my husband about that being strange and waited for 30 seconds more. I then scanned final for 12 without seeing any traffic and started onto the runway when I heard the small aircraft Y aircraft pilot say 'I don't believe that small aircraft X aircraft pulled out in front of me, I am going around.' I cleared the runway back to the hold line and the small aircraft Y proceeded to a landing. My attention had been fixed on the need to allow time for wake turbulence from the large transport aircraft to clear. I still do not understand why I did not see the small aircraft Y aircraft on final unless I looked further out than his position. The transposing of the runway numbers by the small aircraft Y pilot contributed to my belief that plane was somewhere else. I could have avoided the situation by more careful scanning and also by requesting confirmation of position from the small aircraft Y pilot.

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Original NASA ASRS Text

Title: NMAC. PLT OF SMA ACFT INADVERTENTLY TAXIED ONTO RWY IN FRONT OF LNDG TFC AT AN UNCTLED ARPT.

Narrative: AN LGT ACFT HAD LANDED AND I WAS HOLDING AT RWY 12 HOLD LINE FOR WAKE TURB TO CLR. AN SMA Y RPTED FINAL FOR 21. I MADE A REMARK TO MY HUSBAND ABOUT THAT BEING STRANGE AND WAITED FOR 30 SECONDS MORE. I THEN SCANNED FINAL FOR 12 WITHOUT SEEING ANY TFC AND STARTED ONTO THE RWY WHEN I HEARD THE SMA Y ACFT PLT SAY 'I DON'T BELIEVE THAT SMA X ACFT PULLED OUT IN FRONT OF ME, I AM GOING AROUND.' I CLRED THE RWY BACK TO THE HOLD LINE AND THE SMA Y PROCEEDED TO A LNDG. MY ATTN HAD BEEN FIXED ON THE NEED TO ALLOW TIME FOR WAKE TURB FROM THE LGT ACFT TO CLR. I STILL DO NOT UNDERSTAND WHY I DID NOT SEE THE SMA Y ACFT ON FINAL UNLESS I LOOKED FURTHER OUT THAN HIS POS. THE TRANSPOSING OF THE RWY NUMBERS BY THE SMA Y PLT CONTRIBUTED TO MY BELIEF THAT PLANE WAS SOMEWHERE ELSE. I COULD HAVE AVOIDED THE SITUATION BY MORE CAREFUL SCANNING AND ALSO BY REQUESTING CONFIRMATION OF POS FROM THE SMA Y PLT.

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.