What kind of logs were they? According to https://www.archives.gov/research/military/logbooks/other-logs https://www.archives.gov/research/military/logbooks/ot

What kind of logs were they? According to https://www.archives.gov/research/military/logbooks/other-logs https://www.archives.gov/research/military/logbooks/other-lo..., "Only a ship’s Deck Log is retained as a permanent record." Stuff like engineering logs are only retained for three years.