Narrative:

My private pilot student and I were given clearance by hayward tower to taxi from FBO to runway 28R. We proceeded at a normal taxi speed to runway 28R. My student was operating the controls. As my student pilot turned towards the runup area for runway 28R, my push to talk switch fell from my lap to the floor of the aircraft. I diverted my attention to the push to talk switch. At this moment, my student gasped and I looked up and saw the small transport aircraft's left wing tip strike our propeller. I immediately braked and pulled the idle mixture to cut-off. There was no warnings from hayward ground control abut the oncoming small transport aircraft.

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Original NASA ASRS Text

Title: SMA ACFT ON TRAINING FLT, BEING TAXIED BY STUDENT. INSTRUCTOR DISTRACTED, SMA ACFT PROPELLER STRUCK WING TIP OF MOVING SMT ACFT.

Narrative: MY PRIVATE PLT STUDENT AND I WERE GIVEN CLRNC BY HAYWARD TWR TO TAXI FROM FBO TO RWY 28R. WE PROCEEDED AT A NORMAL TAXI SPEED TO RWY 28R. MY STUDENT WAS OPERATING THE CONTROLS. AS MY STUDENT PLT TURNED TOWARDS THE RUNUP AREA FOR RWY 28R, MY PUSH TO TALK SWITCH FELL FROM MY LAP TO THE FLOOR OF THE ACFT. I DIVERTED MY ATTN TO THE PUSH TO TALK SWITCH. AT THIS MOMENT, MY STUDENT GASPED AND I LOOKED UP AND SAW THE SMT ACFT'S LEFT WING TIP STRIKE OUR PROPELLER. I IMMEDIATELY BRAKED AND PULLED THE IDLE MIXTURE TO CUT-OFF. THERE WAS NO WARNINGS FROM HAYWARD GND CTL ABUT THE ONCOMING SMT ACFT.

Data retrieved from NASA's ASRS site as of August 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.