Narrative:

I was teaching a beginning student how to taxi. I went through all the appropriate training, demonstrating use of rudder pedals, and brakes, power. We practiced this on taxiway a toward the takeoff end of runway 15. At this point I let him have full control to taxi the remaining length of taxiway a. He was at 1000 RPM, but I felt for a beginner was going too fast, so I asked him to slow down. He simultaneously added left brake and added power, which had us going extremely rapidly for the grass. I said my controls, pulled out power and stepped on the brakes, but by this time, we couldn't slow down fast enough. So I continued the turn to the left to try and keep it on an intersecting taxiway. Unfortunately the right wheel still struck a taxiway light. To prevent this occurrence in the future, I realize it will take several flts of demonstration of taxiing, and dual controls for proficiency to let the student on the controls alone. I believe my low time as a flight instructor was a large contributing factor as to my judgement in this area.

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Original NASA ASRS Text

Title: A STUDENT PLT TAXIING A C172 WAS CAUTIONED BY THE INSTRUCTOR TO SLOW DOWN. IN ERROR ADDED PWR WITH L BRAKE AND STRUCK A TAXI LIGHT.

Narrative: I WAS TEACHING A BEGINNING STUDENT HOW TO TAXI. I WENT THROUGH ALL THE APPROPRIATE TRAINING, DEMONSTRATING USE OF RUDDER PEDALS, AND BRAKES, PWR. WE PRACTICED THIS ON TXWY A TOWARD THE TKOF END OF RWY 15. AT THIS POINT I LET HIM HAVE FULL CTL TO TAXI THE REMAINING LENGTH OF TXWY A. HE WAS AT 1000 RPM, BUT I FELT FOR A BEGINNER WAS GOING TOO FAST, SO I ASKED HIM TO SLOW DOWN. HE SIMULTANEOUSLY ADDED L BRAKE AND ADDED PWR, WHICH HAD US GOING EXTREMELY RAPIDLY FOR THE GRASS. I SAID MY CTLS, PULLED OUT PWR AND STEPPED ON THE BRAKES, BUT BY THIS TIME, WE COULDN'T SLOW DOWN FAST ENOUGH. SO I CONTINUED THE TURN TO THE L TO TRY AND KEEP IT ON AN INTERSECTING TXWY. UNFORTUNATELY THE R WHEEL STILL STRUCK A TXWY LIGHT. TO PREVENT THIS OCCURRENCE IN THE FUTURE, I REALIZE IT WILL TAKE SEVERAL FLTS OF DEMONSTRATION OF TAXIING, AND DUAL CTLS FOR PROFICIENCY TO LET THE STUDENT ON THE CTLS ALONE. I BELIEVE MY LOW TIME AS A FLT INSTRUCTOR WAS A LARGE CONTRIBUTING FACTOR AS TO MY JUDGEMENT IN THIS AREA.

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.