Narrative:

Flight originated at 5g9 (toledo suburban), mi. Position lights were checked prior to flight. FSS was called and WX briefing was obtained -- no NOTAMS were received in the briefing. I reached my destination and noticed that the left fuel tank was under 1/4 full, and the right one was over 3/4 full. I switched to what I thought was the left tank. I then experienced a power loss. An engine failure check revealed I had switched to the emptier tank instead of the fuller tank. Power was restored only after a 500-600 ft altitude loss. I received a postflt report of an near midair collision with a news helicopter, and a report that my aircraft did not have lights on. On that model cessna, the lighting cannot be checked from inside the cockpit. I was too inattentive when changing fuel tanks. I never saw the helicopter, and was looking for a place to land without hitting a crowd of people below. I estimate my lowest altitude to be 600 ft AGL.

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Original NASA ASRS Text

Title: C172 PLT HAD ENG FUEL STARVATION DUE TO MISHANDLED FUEL SELECTOR. HE ALSO HAD AN NMAC WITH A HELI BECAUSE HIS NAV LIGHTS WERE NOT ON.

Narrative: FLT ORIGINATED AT 5G9 (TOLEDO SUBURBAN), MI. POS LIGHTS WERE CHKED PRIOR TO FLT. FSS WAS CALLED AND WX BRIEFING WAS OBTAINED -- NO NOTAMS WERE RECEIVED IN THE BRIEFING. I REACHED MY DEST AND NOTICED THAT THE L FUEL TANK WAS UNDER 1/4 FULL, AND THE R ONE WAS OVER 3/4 FULL. I SWITCHED TO WHAT I THOUGHT WAS THE L TANK. I THEN EXPERIENCED A PWR LOSS. AN ENG FAILURE CHK REVEALED I HAD SWITCHED TO THE EMPTIER TANK INSTEAD OF THE FULLER TANK. PWR WAS RESTORED ONLY AFTER A 500-600 FT ALT LOSS. I RECEIVED A POSTFLT RPT OF AN NMAC WITH A NEWS HELI, AND A RPT THAT MY ACFT DID NOT HAVE LIGHTS ON. ON THAT MODEL CESSNA, THE LIGHTING CANNOT BE CHKED FROM INSIDE THE COCKPIT. I WAS TOO INATTENTIVE WHEN CHANGING FUEL TANKS. I NEVER SAW THE HELI, AND WAS LOOKING FOR A PLACE TO LAND WITHOUT HITTING A CROWD OF PEOPLE BELOW. I ESTIMATE MY LOWEST ALT TO BE 600 FT AGL.

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.