Narrative:

Entered the pattern in a baron downwind behind a C150. Announced I had C150 in sight. Caught up to the C150 quicker than I had anticipated. Passed on left. Announced I was passing on left. Asked C150 if he would mind if I went ahead in the pattern. He said no problem. Landed and was clear of the active while the C150 was still on final. I found out later from another CFI that the C150 was on a chkride and that the student had gotten rattled when I passed him. I should have announced my intentions sooner or circled to let the C150 continue.

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Original NASA ASRS Text

Title: A BARON PLT RPTS THAT HE STARTLED A C150 PLT BY PASSING THE C150 IN THE TFC PATTERN. ERROR ADMITTED.

Narrative: ENTERED THE PATTERN IN A BARON DOWNWIND BEHIND A C150. ANNOUNCED I HAD C150 IN SIGHT. CAUGHT UP TO THE C150 QUICKER THAN I HAD ANTICIPATED. PASSED ON L. ANNOUNCED I WAS PASSING ON L. ASKED C150 IF HE WOULD MIND IF I WENT AHEAD IN THE PATTERN. HE SAID NO PROB. LANDED AND WAS CLR OF THE ACTIVE WHILE THE C150 WAS STILL ON FINAL. I FOUND OUT LATER FROM ANOTHER CFI THAT THE C150 WAS ON A CHKRIDE AND THAT THE STUDENT HAD GOTTEN RATTLED WHEN I PASSED HIM. I SHOULD HAVE ANNOUNCED MY INTENTIONS SOONER OR CIRCLED TO LET THE C150 CONTINUE.

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.