After MUCH hindsight, the usual culprits - faulty boat design, couple mechanical failures, bad weather forecast, stupidity (ours), all came together just right. Three of us were king fishing off of the Dredge Wreck out of Carolina Beach.
Forecast was common for summer - 10-15 mph, 1'-3', but waves built to head high and cresting. Boat was a 20' Sea Ox with open transom, so with rough seas we had water on deck all day (not too unusual for us). The steering cable/wiring were routed below the console through a 6" flush access fitting so during the day the waves repeatedly washed under the console, and we believe water fell through the flush deck access and gradually filled the bilge spaces. Bilge pump was inop when the boat was recovered (3 days later off of Morehead) so the bilge did not get cleared and we lost flotation. Weather kept going south (pun intended) and we turned downsea to recover the downrigger balls and head back in. Motor quit, no restart, don't know why but guessing salt water over the battery? I grabbed the 6 gal tank to start the 15 hp backup motor, wave over the transom hit hit me in the knees. Just had time for one "mayday, mayday at the Dredge wreck" and we rolled. Maybe 20-30 seconds from when the motor quit. Brother dove under the boat and found one PFD, rest were trapped under boat or had floated off. I stood on the bow rail holding the lifting eye, the other 2 held onto me.

Turns out USCG heard the mayday and responded. We did not answer, antenna was pointing the wrong way by then. They chalked it up to a false alarm (you may find I'm funny about false VHF reports or people tying up Ch 16 with radio checks). A 30' SeaRay Foolish Pleasure heard the mayday and happened to have a RDF - they pulled their lines, ran down their bearing a few miles and found us. They positioned upsea of the hull and picked up up the other 2 guys. When it was my turn, I swam behind their boat but the seas were pushing the two boats together so they hit their motors to avoid a collision - motor wash picked me up and threw me over the capsized hull. They came around and picked me up, brought us in to USCG at Masonboro. Try explaining that situation to a wife with a newborn and a 2 year old. All I can say is somebody was looking our for fools that day. Never did get to properly thank the Foolish Pleasure either.

Lessons (my stupidity): I don't go offshore in a boat with no transom. Bilge pumps and engines quit in awkward moments. I'm conservative on weather, and when it kicks up, I go inside. I try not to overload a boat (did I mention the 55 gallon drum we had on deck as a home-made bait well?). I wear an inflatable PFD when fishing alone, have a PLB, and a life raft. My DSC and MMSI are hooked up on my VHF. I don't go offshore in a boat with no transom.

Sorry you asked???