Narrative:

I was working in the pattern, practicing touch-and-go lndgs. This was my first landing of the day. The runway in use was runway 24, which was the usual runway assigned by ATC. The wind was variable at 3-4 KTS, which generally requires some control inputs on short final due to thermals. I had flaps at 20%, airspeed was 68 KIAS, and I was on the VASI. After touchdown, I raised the flaps and applied full power. I applied a small amount of right rudder (compensating for torque). The airplane felt like it wasn't handling properly and started to weave left. As I veered off the left side of the runway, the weaving got more and more exaggerated and I picked up speed. I pushed in the throttle. I did not verify my airspeed indicator, but imagine I was doing about 55 KIAS. I had all I could do to maintain a relatively straight path across the grass between the runway and taxiway. ATC diverted a landing aircraft on short final during this time and asked if I was ok. I had regained control and was moving across the infield, still in a relative straight line, making for a taxiway to get back to the FBO. I did not hit anything during the incident (lights, runway signs, etc) but the C172 took some good bumps. I believe the cause of the incident was, the heel of my feet not being on the floor when I began applying rudder input for the takeoff. This would have actuated the brakes, and my attempts initially to control the airplane only made matters worse. While taxiing back to the FBO, the brakes worked fine and all control inputs felt normal. The mechanic checked out the plane and I returned to finish up my practice touch-and-go's without further incident. I can't explain why I went off the left side of the runway if I was braking right. Unless, I started a slight movement to the right and applied left rudder (brake) to compensate. Thinking back, this is not too clear.

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Original NASA ASRS Text

Title: C172 PLT HAS RWY EXCURSION AT POU.

Narrative: I WAS WORKING IN THE PATTERN, PRACTICING TOUCH-AND-GO LNDGS. THIS WAS MY FIRST LNDG OF THE DAY. THE RWY IN USE WAS RWY 24, WHICH WAS THE USUAL RWY ASSIGNED BY ATC. THE WIND WAS VARIABLE AT 3-4 KTS, WHICH GENERALLY REQUIRES SOME CTL INPUTS ON SHORT FINAL DUE TO THERMALS. I HAD FLAPS AT 20%, AIRSPD WAS 68 KIAS, AND I WAS ON THE VASI. AFTER TOUCHDOWN, I RAISED THE FLAPS AND APPLIED FULL PWR. I APPLIED A SMALL AMOUNT OF R RUDDER (COMPENSATING FOR TORQUE). THE AIRPLANE FELT LIKE IT WASN'T HANDLING PROPERLY AND STARTED TO WEAVE L. AS I VEERED OFF THE L SIDE OF THE RWY, THE WEAVING GOT MORE AND MORE EXAGGERATED AND I PICKED UP SPD. I PUSHED IN THE THROTTLE. I DID NOT VERIFY MY AIRSPD INDICATOR, BUT IMAGINE I WAS DOING ABOUT 55 KIAS. I HAD ALL I COULD DO TO MAINTAIN A RELATIVELY STRAIGHT PATH ACROSS THE GRASS BTWN THE RWY AND TXWY. ATC DIVERTED A LNDG ACFT ON SHORT FINAL DURING THIS TIME AND ASKED IF I WAS OK. I HAD REGAINED CTL AND WAS MOVING ACROSS THE INFIELD, STILL IN A RELATIVE STRAIGHT LINE, MAKING FOR A TXWY TO GET BACK TO THE FBO. I DID NOT HIT ANYTHING DURING THE INCIDENT (LIGHTS, RWY SIGNS, ETC) BUT THE C172 TOOK SOME GOOD BUMPS. I BELIEVE THE CAUSE OF THE INCIDENT WAS, THE HEEL OF MY FEET NOT BEING ON THE FLOOR WHEN I BEGAN APPLYING RUDDER INPUT FOR THE TKOF. THIS WOULD HAVE ACTUATED THE BRAKES, AND MY ATTEMPTS INITIALLY TO CTL THE AIRPLANE ONLY MADE MATTERS WORSE. WHILE TAXIING BACK TO THE FBO, THE BRAKES WORKED FINE AND ALL CTL INPUTS FELT NORMAL. THE MECH CHKED OUT THE PLANE AND I RETURNED TO FINISH UP MY PRACTICE TOUCH-AND-GO'S WITHOUT FURTHER INCIDENT. I CAN'T EXPLAIN WHY I WENT OFF THE L SIDE OF THE RWY IF I WAS BRAKING R. UNLESS, I STARTED A SLIGHT MOVEMENT TO THE R AND APPLIED L RUDDER (BRAKE) TO COMPENSATE. THINKING BACK, THIS IS NOT TOO CLR.

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.