Narrative:

[The night before] I filled the aircraft. Both tanks were full. [The following morning my passenger and I] departed [our home airport] and flew to [an intermediate stop] where we picked up two [additional passengers]. From there we flew to [another airport] about 80 miles and had lunch. When we departed; I looked at the fuel totalizer on the instrument panel and saw that we had used 9.9 gallons. I did not look at the fuel quantity indicators which are located in the wing roots. When we were about 8 miles from home the engine quit. I called ZZZ center; gave them our position and activated the 406 ELT. We landed in a marsh and flipped over. Everyone exited the aircraft and waited on the wing until the [state] troopers helicopter arrived. There were no injuries. After the aircraft was recovered by helicopter; I notices the right fuel cap was off.

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Original NASA ASRS Text

Title: Small aircraft pilot reported an engine failure inflight resulting in an off airport forced landing and aircraft damage.

Narrative: [The night before] I filled the aircraft. Both tanks were full. [The following morning my passenger and I] departed [our home airport] and flew to [an intermediate stop] where we picked up two [additional passengers]. From there we flew to [another airport] about 80 miles and had lunch. When we departed; I looked at the fuel totalizer on the instrument panel and saw that we had used 9.9 gallons. I did not look at the fuel quantity indicators which are located in the wing roots. When we were about 8 miles from home the engine quit. I called ZZZ Center; gave them our position and activated the 406 ELT. We landed in a marsh and flipped over. Everyone exited the aircraft and waited on the wing until the [State] Troopers helicopter arrived. There were no injuries. After the aircraft was recovered by helicopter; I notices the right fuel cap was off.

Data retrieved from NASA's ASRS site 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.