RedactedNarrative: Two met at around 9:00 on March 27 2023 at Browns Ferry Marina.  The party was meeting to drive a 41 ft Viking boat, that Operator  had purchased, to a marina on Chickamauga Lake.  Operator checked oil levels and did other maintenance checks.  The two departed around 9:30 heading up river.  They arrived at Erwin Marina around 10:00 and got fuel.  They resumed their voyage and headed up river to go through the Chickamauga Dam lock.  As they were waiting for the lock to allow them in Operator began to notice a slight bit of smoke coming from the port engine.  Operator stated that as they entered the lock he lost throttle control of the boat.  And they made it into the lock on their momentum.  Operator stated that they notified the lockmaster that they were having issues.  Subject also stated that the automatic fire supression system came on and they thought the fire had gone out.  TVA sent a boat out to assit and tow the Viking vessel out of the lock.  Operator stated that as they were being towed the smoke began to get worse.  Operator stated that a significant amount of black smoke was begining to come from the engines as they approached the wing wall of the lock.  They attempted to put the fire out with fire extinguishers but that did not work.  Both occupants were forced to climb up a ladder on the wing wall to safety.
  
  I arrived on scene around 12:00 with Officer .  Leuitenant was alread on scence and had begun talking with the operator/owner -.  I took a statement from operator1 while Leuitenant talked to the passenger.  As we were finishing up the statements the vessel began to sink near the opening of the lock.  The vessel sank quickly and was completely submerged.
  
  While talking to Operator I learned that he had purchased the vessel from another.  He stated that he had aquired insurance for the boat.  He had not registered the vessel in his name.  He has stated he will provide proof of purchase documents to me in the coming days.  
  
  Lt. contacted Towboat USA to assist with recovering the vessel.  Towboat was enroute to the scene at the time we left.
  
  Shortly after speaking to Operator and watching the vessel sink, Officer, Lt., and I left the scene at approximately 13:00.  Officer was arriving on scene and departed when we did.
  
  *Pictures of accident site and boat sinking area attached
  *Incident reports from Officer and Lt. are attached as PDF''s
  *No injuries reported
NameOfBodyOfWater: CHICKAMAUGA RESERVOIR
NearestCityTown: CHATTANOOGA                   