Narrative:

The ground around the airport was patchy covered with snow -- giving it a mottled look. Features on the ground were not very clear and distinguished (a minor contributing factor). On short final I started to think, 'this looks narrow,' and I wondered if there was a displaced threshold, and I was wondering, 'why is the centerline yellow?' I continued fat, dumb and happy to a nice touchdown and touch and go on the taxiway which parallels runway 29L. Upon climb out I noticed I hadn't pushed in the carburetor heat -- even though I went (mentally) through touch and go checklist. Another sign of being behind the plane and not thinking. It was only on downwind, looking for/at the runway for my next touch and go that I realized I had done my last one on the parallel. I then did 2 more touch and goes on runway 29L. I don't think the tower noticed, because nothing was said. I was surprised at how easily it happened, even with the questions coming to mind. Some factors: lack of recent experience over the last 5 yrs or so, but that's why I was up there doing touch and goes. Not thinking ahead of the plane or about what I should be doing or seeing. Terrain blurred because of snow. Also, I flew a lot in alaska, and many of the strips I landed on up there were unimproved or small, paved strips. The parallel taxiway looked like lots of runways I've landed on before -- it didn't look out of place to me. I just failed to see/anticipate a normally marked paved runway right next to it.

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Original NASA ASRS Text

Title: C172 PLT PERFORMED A TOUCH AND GO TO THE PARALLEL TAXIWAY.

Narrative: THE GND AROUND THE ARPT WAS PATCHY COVERED WITH SNOW -- GIVING IT A MOTTLED LOOK. FEATURES ON THE GND WERE NOT VERY CLR AND DISTINGUISHED (A MINOR CONTRIBUTING FACTOR). ON SHORT FINAL I STARTED TO THINK, 'THIS LOOKS NARROW,' AND I WONDERED IF THERE WAS A DISPLACED THRESHOLD, AND I WAS WONDERING, 'WHY IS THE CTRLINE YELLOW?' I CONTINUED FAT, DUMB AND HAPPY TO A NICE TOUCHDOWN AND TOUCH AND GO ON THE TXWY WHICH PARALLELS RWY 29L. UPON CLBOUT I NOTICED I HADN'T PUSHED IN THE CARB HEAT -- EVEN THOUGH I WENT (MENTALLY) THROUGH TOUCH AND GO CHKLIST. ANOTHER SIGN OF BEING BEHIND THE PLANE AND NOT THINKING. IT WAS ONLY ON DOWNWIND, LOOKING FOR/AT THE RWY FOR MY NEXT TOUCH AND GO THAT I REALIZED I HAD DONE MY LAST ONE ON THE PARALLEL. I THEN DID 2 MORE TOUCH AND GOES ON RWY 29L. I DON'T THINK THE TWR NOTICED, BECAUSE NOTHING WAS SAID. I WAS SURPRISED AT HOW EASILY IT HAPPENED, EVEN WITH THE QUESTIONS COMING TO MIND. SOME FACTORS: LACK OF RECENT EXPERIENCE OVER THE LAST 5 YRS OR SO, BUT THAT'S WHY I WAS UP THERE DOING TOUCH AND GOES. NOT THINKING AHEAD OF THE PLANE OR ABOUT WHAT I SHOULD BE DOING OR SEEING. TERRAIN BLURRED BECAUSE OF SNOW. ALSO, I FLEW A LOT IN ALASKA, AND MANY OF THE STRIPS I LANDED ON UP THERE WERE UNIMPROVED OR SMALL, PAVED STRIPS. THE PARALLEL TXWY LOOKED LIKE LOTS OF RWYS I'VE LANDED ON BEFORE -- IT DIDN'T LOOK OUT OF PLACE TO ME. I JUST FAILED TO SEE/ANTICIPATE A NORMALLY MARKED PAVED RWY RIGHT NEXT TO IT.

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.