Narrative:

Departed uncontrolled airport (lbf) in conditions of less than three miles visibility. Control zone around airport is poorly marked on world chart so I did not realize I was in a control zone. Although I had visibility of one mile and remained clear of clouds, I failed to obtain a special VFR clearance. I knew WX conditions were excellent VFR (15 miles visibility) just east of the field. I departed the field to the east declaring my intentions and position on the unicom/CTAF frequency 122.95. The flight was conducted without any problems or traffic conflicts of any type. After review of the flight the following day on a sectional chart I realized lbf was in a control zone.

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Original NASA ASRS Text

Title: FLT FROM CONTROL ZONE BELOW VFR MINIMUMS WITHOUT CLRNC.

Narrative: DEPARTED UNCTLED ARPT (LBF) IN CONDITIONS OF LESS THAN THREE MILES VISIBILITY. CTL ZONE AROUND ARPT IS POORLY MARKED ON WORLD CHART SO I DID NOT REALIZE I WAS IN A CTL ZONE. ALTHOUGH I HAD VISIBILITY OF ONE MILE AND REMAINED CLEAR OF CLOUDS, I FAILED TO OBTAIN A SPECIAL VFR CLRNC. I KNEW WX CONDITIONS WERE EXCELLENT VFR (15 MILES VISIBILITY) JUST E OF THE FIELD. I DEPARTED THE FIELD TO THE E DECLARING MY INTENTIONS AND POSITION ON THE UNICOM/CTAF FREQ 122.95. THE FLT WAS CONDUCTED WITHOUT ANY PROBS OR TFC CONFLICTS OF ANY TYPE. AFTER REVIEW OF THE FLT THE FOLLOWING DAY ON A SECTIONAL CHART I REALIZED LBF WAS IN A CTL ZONE.

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.