RedactedNarrative: Vessel 1 (V1) was traveling west within the north Gulf Harbors Channel. The operator of V1 noticed that the vessel was taking on water. V1 continued traveling west towards the north Anclote Sandbar. Approximately halfway to the Sandbar, V1 became swamped. V1 stopped and broadcasted a "Mayday" call on the VHF radio. An occupant of V1 was able to flag down a nearby vessel "Good Samaritan vessel." The "Good Samaritan vessel" was able to tow V1 to the Sandbar. All but two occupants of V1 were taken, by the "Good Samaritan vessel," to a residence in Gulf Harbors. BoatUS arrived on scene and towed V1 to the Anclote River Boat Ramp. V1 was removed from the water by the owner. 
  
  I observed damage to the port side of the vessel, midway, along the chine. The damage was approximately 6 feet in length.  BoatUS towed the listed vessel to the Anclote River Park Boat Ramp. Operator left the scene to retrieve a trailer for the vessel. I spoke with subject on the listed vessel. subject was able to assist OFC (FWC) and I in a current boating safety inspection of the listed vessel. subject provided a written statement, refer to the attached written statement. 
  
  According to both Operator and subject, the listed vessel did not strike anything. The listed vessel suddenly and unexpectedly started taking on water. Operator did confirm that the stern of the vessel, to include both engines, were underwater. I was able to obtain the listed synopsis from statements provided by Operator and subject. Both subjects provided information to me for the completion of this report. 
  
  Upon further inspection of the vessel, the fiberglass in the damaged area appeared black. It seemed that the fiberglass was old and rotted. It did appear that the fiberglass had collapsed and was structurally unstable. Based on the available evidence and statements, it does not appear that the listed vessel collided with a fixed or non-fixed object. A check with the Pasco Sheriff's Office did not reveal any recent calls which involved the listed vessel. I provided Operator my business card, along with this case number and report number. I directed Operator to contact me with any further information or questions.