Narrative:

I supervised my student preflting the aircraft and noticed frost all over the leading edge of the wings. We taxied the aircraft to the wash rack and I cleared the aircraft of frost and reinspected the aircraft paying particular attention to control surfaces, etc. It was all ok. The aircraft was dripping wet from the wash I had given it. It was a sunny morning. I expected the water on the windshield to blow off during the runup and takeoff roll. Runup was uneventful and student asked for clearance to takeoff, which he received. He taxied into position and began to apply full power. However, the sun was shining directly through the window into our eyes. The sunlight was reflecting off the wet window and the slightly foggy interior of window pto resulted in virtual blindness. I aborted the takeoff (we got no faster than the taxi stage) without incident. I thought this was a really interesting occurrence because I've always read about removing frost, etc, from aircraft, but have routinely taken off with wet windows and wet aircraft. I've also seen numerous other people takeoff under the same circumstances. My student and I returned to the FBO and thoroughly dried all the aircraft's windows, inside and out, prior to taxiing back out again. I conducted a thorough debrief and the whole event was a good learning experience for both of us. My heavy flight bag has had a couple of towels stuffed in it since! The window had been perfectly clear when taxiing away from the sun, but impossible to see through when facing the sun.

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Original NASA ASRS Text

Title: SMA TKOF ABORTED WHEN VISIBILITY THROUGH THE WINDSHIELD IS SUDDENLY OBSCURED.

Narrative: I SUPERVISED MY STUDENT PREFLTING THE ACFT AND NOTICED FROST ALL OVER THE LEADING EDGE OF THE WINGS. WE TAXIED THE ACFT TO THE WASH RACK AND I CLRED THE ACFT OF FROST AND REINSPECTED THE ACFT PAYING PARTICULAR ATTN TO CTL SURFACES, ETC. IT WAS ALL OK. THE ACFT WAS DRIPPING WET FROM THE WASH I HAD GIVEN IT. IT WAS A SUNNY MORNING. I EXPECTED THE WATER ON THE WINDSHIELD TO BLOW OFF DURING THE RUNUP AND TKOF ROLL. RUNUP WAS UNEVENTFUL AND STUDENT ASKED FOR CLRNC TO TKOF, WHICH HE RECEIVED. HE TAXIED INTO POS AND BEGAN TO APPLY FULL PWR. HOWEVER, THE SUN WAS SHINING DIRECTLY THROUGH THE WINDOW INTO OUR EYES. THE SUNLIGHT WAS REFLECTING OFF THE WET WINDOW AND THE SLIGHTLY FOGGY INTERIOR OF WINDOW PTO RESULTED IN VIRTUAL BLINDNESS. I ABORTED THE TKOF (WE GOT NO FASTER THAN THE TAXI STAGE) WITHOUT INCIDENT. I THOUGHT THIS WAS A REALLY INTERESTING OCCURRENCE BECAUSE I'VE ALWAYS READ ABOUT REMOVING FROST, ETC, FROM ACFT, BUT HAVE ROUTINELY TAKEN OFF WITH WET WINDOWS AND WET ACFT. I'VE ALSO SEEN NUMEROUS OTHER PEOPLE TKOF UNDER THE SAME CIRCUMSTANCES. MY STUDENT AND I RETURNED TO THE FBO AND THOROUGHLY DRIED ALL THE ACFT'S WINDOWS, INSIDE AND OUT, PRIOR TO TAXIING BACK OUT AGAIN. I CONDUCTED A THOROUGH DEBRIEF AND THE WHOLE EVENT WAS A GOOD LEARNING EXPERIENCE FOR BOTH OF US. MY HVY FLT BAG HAS HAD A COUPLE OF TOWELS STUFFED IN IT SINCE! THE WINDOW HAD BEEN PERFECTLY CLR WHEN TAXIING AWAY FROM THE SUN, BUT IMPOSSIBLE TO SEE THROUGH WHEN FACING THE SUN.

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.