The ship's complement and passenger lists cited 6,050 people on board, but these did not include many civilians who boarded the ship without being recorded in the official embarkation records. Heinz Schön, a German archivist and "Gustloff" survivor who extensively researched the sinking during the 1980s and 1990s, concluded that she was carrying a crew of 173 (naval armed forces auxiliaries); 918 officers, NCOs, and men of the 2 "Unterseeboot-Lehrdivision"; 373 female naval auxiliary helpers; 162 wounded soldiers' and 8,956 civilians, for a total of 10,582 passengers and crew. The passengers, besides civilians, included Gestapo personnel, members of the Organisation Todt, and Nazi officials with their families. The ship was overcrowded, and due to the temperature and humidity inside, many passengers defied orders not to remove their life jackets.