Narrative:

I was planning a VFR night flight with a student. Due to his unfamiliarity with the aircraft, I did the walkaround with him. I showed him where the microswitches for the gear were and at the same time lying under the aircraft, I showed him how to check the brakes for leakage and the thickness of the pads. After completing the preflight we pulled the aircraft out of the parking spot to face the taxiway. This aircraft does not have brakes on the instructor's side, therefore I pulled the hand brake on. I talked him through the starting procedures with the checklist and let him start the left engine. The engine started up right away and the aircraft started to move to the right. My student panicked and, because of his unfamiliarity, pushed the throttle full forward and locked his arm. By then I had cut the mixture but the aircraft was still rolling and the windmilling propeller hit the tip-tank of another airplane.

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Original NASA ASRS Text

Title: ACFT TAXI INTO ANTHER ACFT.

Narrative: I WAS PLANNING A VFR NIGHT FLT WITH A STUDENT. DUE TO HIS UNFAMILIARITY WITH THE ACFT, I DID THE WALKAROUND WITH HIM. I SHOWED HIM WHERE THE MICROSWITCHES FOR THE GEAR WERE AND AT THE SAME TIME LYING UNDER THE ACFT, I SHOWED HIM HOW TO CHK THE BRAKES FOR LEAKAGE AND THE THICKNESS OF THE PADS. AFTER COMPLETING THE PREFLT WE PULLED THE ACFT OUT OF THE PARKING SPOT TO FACE THE TXWY. THIS ACFT DOES NOT HAVE BRAKES ON THE INSTRUCTOR'S SIDE, THEREFORE I PULLED THE HAND BRAKE ON. I TALKED HIM THROUGH THE STARTING PROCS WITH THE CHKLIST AND LET HIM START THE L ENG. THE ENG STARTED UP RIGHT AWAY AND THE ACFT STARTED TO MOVE TO THE R. MY STUDENT PANICKED AND, BECAUSE OF HIS UNFAMILIARITY, PUSHED THE THROTTLE FULL FORWARD AND LOCKED HIS ARM. BY THEN I HAD CUT THE MIXTURE BUT THE ACFT WAS STILL ROLLING AND THE WINDMILLING PROP HIT THE TIP-TANK OF ANOTHER AIRPLANE.

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.