Narrative:

During instruction leading to tailwheel PIC endorsement. Transitioning student to takeoffs and lndgs on hard surfaced runway, after practicing in dirt runway. Aircraft is a PA18 (super cub) with tundra tires. These tires, being much larger, make the handling much trickier on landing, as they bounce more and make the aircraft more difficult to control on touchdown and rollout. I was in the rear seat, so my view was restr. I had the student practicing 3 point lndgs with 2 notches of flaps. He was making good progress, and we were about 1/2 way through the training. On this approach, as the student was attempting a 3 point landing, the final approach looked good. As he flared and touched down, he had just a bit of excess airspeed and bounced back up. As we bounced up, the wind shifted to the left, and we started drifting left and airspeed dropped off. I could not see all of this. He applied left aileron but no rudder. The tail started to come around, and before I realized what had happened, we were suddenly veering off the runway into the weeds. Full rudder did not help. The brakes were not effective. We did a slow ground loop, going off the runway, and the left wingtip just grazed the ground, tearing the fabric. A local mechanic inspected the wing and airframe, and could find no structural damage. First some torn fabric and slightly bent ribs. He said it was ok to fly. I flew it back to hurricane airport, about a 15 min flight. It handled normally. We had taped the torn fabric. For future reference, I will not recommend a transitioning student use an airplane with tundra tires, smaller tires are easier to handle initially. And I will have to be more on top of the situation. Can't relax for a second. I will also emphasize more rudder practice drills prior to pattern work.

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Original NASA ASRS Text

Title: A PA18 GND LOOPED ON AN INSTRUCTIONAL FLT. THE L WINGTIP CONTACTED THE GND WITH MINOR DAMAGE.

Narrative: DURING INSTRUCTION LEADING TO TAILWHEEL PIC ENDORSEMENT. TRANSITIONING STUDENT TO TKOFS AND LNDGS ON HARD SURFACED RWY, AFTER PRACTICING IN DIRT RWY. ACFT IS A PA18 (SUPER CUB) WITH TUNDRA TIRES. THESE TIRES, BEING MUCH LARGER, MAKE THE HANDLING MUCH TRICKIER ON LNDG, AS THEY BOUNCE MORE AND MAKE THE ACFT MORE DIFFICULT TO CTL ON TOUCHDOWN AND ROLLOUT. I WAS IN THE REAR SEAT, SO MY VIEW WAS RESTR. I HAD THE STUDENT PRACTICING 3 POINT LNDGS WITH 2 NOTCHES OF FLAPS. HE WAS MAKING GOOD PROGRESS, AND WE WERE ABOUT 1/2 WAY THROUGH THE TRAINING. ON THIS APCH, AS THE STUDENT WAS ATTEMPTING A 3 POINT LNDG, THE FINAL APCH LOOKED GOOD. AS HE FLARED AND TOUCHED DOWN, HE HAD JUST A BIT OF EXCESS AIRSPD AND BOUNCED BACK UP. AS WE BOUNCED UP, THE WIND SHIFTED TO THE L, AND WE STARTED DRIFTING L AND AIRSPD DROPPED OFF. I COULD NOT SEE ALL OF THIS. HE APPLIED L AILERON BUT NO RUDDER. THE TAIL STARTED TO COME AROUND, AND BEFORE I REALIZED WHAT HAD HAPPENED, WE WERE SUDDENLY VEERING OFF THE RWY INTO THE WEEDS. FULL RUDDER DID NOT HELP. THE BRAKES WERE NOT EFFECTIVE. WE DID A SLOW GND LOOP, GOING OFF THE RWY, AND THE L WINGTIP JUST GRAZED THE GND, TEARING THE FABRIC. A LCL MECH INSPECTED THE WING AND AIRFRAME, AND COULD FIND NO STRUCTURAL DAMAGE. FIRST SOME TORN FABRIC AND SLIGHTLY BENT RIBS. HE SAID IT WAS OK TO FLY. I FLEW IT BACK TO HURRICANE ARPT, ABOUT A 15 MIN FLT. IT HANDLED NORMALLY. WE HAD TAPED THE TORN FABRIC. FOR FUTURE REF, I WILL NOT RECOMMEND A TRANSITIONING STUDENT USE AN AIRPLANE WITH TUNDRA TIRES, SMALLER TIRES ARE EASIER TO HANDLE INITIALLY. AND I WILL HAVE TO BE MORE ON TOP OF THE SIT. CAN'T RELAX FOR A SECOND. I WILL ALSO EMPHASIZE MORE RUDDER PRACTICE DRILLS PRIOR TO PATTERN WORK.

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.