Narrative:

Turned close-in downwind and had received and acknowledged a clearance for the option 28L. Traffic called - helicopter southeast at 800 ft responded 'looking; I'm at 1;200.' looking out the right side for chopper. Very close to the airport; assumed I was inside the chopper traffic. Faster aircraft behind me.at the abeam point tower again cleared me; stating I was number one. I again recited 28 left with my abbreviated n-number; and said 'I will make it quick;' thinking that the stearman behind me was gaining. Again; I thought the helicopter was southeast of my position; and was not aware he was landing.he saw me first; and took evasive action. This was very close to the airport. I did not see him until it was over - he was above me; framed in my windshield.

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Original NASA ASRS Text

Title: Although not yet in visual contact with helicopter traffic in the pattern the pilot of a Piper J-3; number one for the runway; set up for a short final and experienced an NMAC with the traffic.

Narrative: Turned close-in downwind and had received and acknowledged a clearance for the option 28L. Traffic called - helicopter southeast at 800 FT responded 'looking; I'm at 1;200.' Looking out the right side for chopper. Very close to the airport; assumed I was inside the chopper traffic. Faster aircraft behind me.At the abeam point Tower again cleared me; stating I was number one. I again recited 28 left with my abbreviated N-number; and said 'I will make it quick;' thinking that the Stearman behind me was gaining. Again; I thought the helicopter was southeast of my position; and was not aware he was landing.He saw me first; and took evasive action. This was very close to the airport. I did not see him until it was over - he was above me; framed in my windshield.

Data retrieved from NASA's ASRS site as of July 2013 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.