Production Designer [[Jerry Wanek]] reports that [http://www.htrnews.com/story/news/local/2016/02/16/supernatural-airs-cobia-inspired-episode/80462820/ the submarine set was built] on the ''Supernatural'' sound stage and was 100 feet long and took 80 people two weeks to construct. The design was based on ''USS Cobia'' submarine, a National Historic Landmark at the Wisconsin Maritime Museum and the ''USS Bowfin'' in Hawaii.
* [http://www.robertwmackay.ca/supernatural-submarine/ Read a blog post by the technical advisor on the construction]