The operator noticed a green/yellow smoke coming from the AFT section of his deck boat.  He and his wife put on life jackets and helped the kids on board into the water.  (All the children were already wearing pfd's.)  The boat became engulfed in flames and floated with the river current.  It came to rest on a wing dam aprroximately a mile south.  A sonar search was unable to locate the wreckage.
Quincy                        