 Reportedly as a result of his refusal to fully support the Navy 's position , Moosally 's Navy career was over . A request for his retirement , whether made by Moosally or someone else is unclear , was approved a few days later . The Navy later reopened its investigation and eventually concluded that it could not determine who or what had caused the tragedy . An independent review of the Navy 's investigation by Sandia National Laboratories concluded that the explosion had probably been caused by an overram of the powder bags into the center gun 's breech , possibly because of a malfunction in the rammer mechanism or because the gun crew was inadequately trained . 
