Narrative:

I was doing my run-up on the taxiway, waiting for takeoff at traverse city, runway 28. It sounded like a plane was coming in after the twin small aircraft that just landed, and that the controller wanted to fit me in between them. I called and said I was ready for takeoff and I thought she cleared me for takeoff. I was only doing what I thought I was supposed to do, and in trying to help out, and get out of the way of the plane coming in. I shortened my communications and only answered with my call sign after the controller's instruction. I did not see the small aircraft on the runway when I lined up on takeoff. The runway was snowy, and the small aircraft was obscured from my vision by snow from his up-wash. I took off, and did not see the small aircraft until I was airborne. He was no factor, at least 2000- 3000 ft. The controller yelled at me, saying I was not cleared for takeoff, as the small aircraft exited onto his taxiway. I apologized and said I must have misunderstood her. Like I said, I did what I thought I was supposed to do. I talked to the ATC superintendent, and he said it was done and over with, and to chalk it up as a learning experience. Our chief flight instructor counseled me on the new rule about repeating runway instructions to ATC, to avoid further future runway incursions. I also watched the FAA 'runway incursions' video tape. I now make sure I repeat back all runway instructions.

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Original NASA ASRS Text

Title: AN SMA PLT TOOK OFF WITHOUT CLRNC. HE FLEW OVER THE BACK OF AN ACFT THAT WAS TURNING OFF OF THE RWY.

Narrative: I WAS DOING MY RUN-UP ON THE TXWY, WAITING FOR TKOF AT TRAVERSE CITY, RWY 28. IT SOUNDED LIKE A PLANE WAS COMING IN AFTER THE TWIN SMA THAT JUST LANDED, AND THAT THE CTLR WANTED TO FIT ME IN BTWN THEM. I CALLED AND SAID I WAS READY FOR TKOF AND I THOUGHT SHE CLRED ME FOR TKOF. I WAS ONLY DOING WHAT I THOUGHT I WAS SUPPOSED TO DO, AND IN TRYING TO HELP OUT, AND GET OUT OF THE WAY OF THE PLANE COMING IN. I SHORTENED MY COMS AND ONLY ANSWERED WITH MY CALL SIGN AFTER THE CTLR'S INSTRUCTION. I DID NOT SEE THE SMA ON THE RWY WHEN I LINED UP ON TKOF. THE RWY WAS SNOWY, AND THE SMA WAS OBSCURED FROM MY VISION BY SNOW FROM HIS UP-WASH. I TOOK OFF, AND DID NOT SEE THE SMA UNTIL I WAS AIRBORNE. HE WAS NO FACTOR, AT LEAST 2000- 3000 FT. THE CTLR YELLED AT ME, SAYING I WAS NOT CLRED FOR TKOF, AS THE SMA EXITED ONTO HIS TXWY. I APOLOGIZED AND SAID I MUST HAVE MISUNDERSTOOD HER. LIKE I SAID, I DID WHAT I THOUGHT I WAS SUPPOSED TO DO. I TALKED TO THE ATC SUPERINTENDENT, AND HE SAID IT WAS DONE AND OVER WITH, AND TO CHALK IT UP AS A LEARNING EXPERIENCE. OUR CHIEF FLT INSTRUCTOR COUNSELED ME ON THE NEW RULE ABOUT REPEATING RWY INSTRUCTIONS TO ATC, TO AVOID FURTHER FUTURE RWY INCURSIONS. I ALSO WATCHED THE FAA 'RWY INCURSIONS' VIDEO TAPE. I NOW MAKE SURE I REPEAT BACK ALL RWY INSTRUCTIONS.

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.