Distraction; Troubleshooting; Time Pressure; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Fuel Issue
Air Traffic Control Provided Assistance; Aircraft Aircraft Damaged; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action; General Evacuated
Aircraft
[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.
Pilot stated the missing fuel cap caused fuel starvation.
Small aircraft pilot reported an engine failure inflight resulting in an off airport forced landing and aircraft damage.