Narrative:

Flying up river canyon at 400 ft AGL came around a corner, saw bridge. Flew about 250 ft over bridge, was cited for flying under 1000 ft AGL by blm. I did not know about altitude restrs. FAA part 103 does not require to know these rules, but I know this one now.

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Original NASA ASRS Text

Title: ULTRA LIGHT ACFT FLIES OVER RIVER BRIDGE IN REMOTE AREA AT 250 FT AND IS CITED BY GOV BLM FOR NOT BEING 1000 FT OVER IT.

Narrative: FLYING UP RIVER CANYON AT 400 FT AGL CAME AROUND A CORNER, SAW BRIDGE. FLEW ABOUT 250 FT OVER BRIDGE, WAS CITED FOR FLYING UNDER 1000 FT AGL BY BLM. I DID NOT KNOW ABOUT ALT RESTRS. FAA PART 103 DOES NOT REQUIRE TO KNOW THESE RULES, BUT I KNOW THIS ONE NOW.

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.