|Class and type:||Research submarine|
|Beam:||0.72 metres (2 ft 4 in)|
|Test depth:||105 metres (344 ft)|
Speleonaut (named from the Greek words for "cave" and "sailor") is the submersible used by the cave diver Jochen Hasenmayer. After the 1989 decompression accident that left his legs paralyzed, Hasenmayer designed the Speleonaut with his friend Konrad Gehringer in order to continue exploring the Blauhöhle cave system, which begins at the base of the Blautopf spring in the Swabian Jura mountain range. The Speleonaut is 72 centimetres (28 in) wide and has nine engines, making it easy to maneuver in all directions. It is the first submarine designed specifically for the exploration of caves. According to Hasenmayer, the Speleonaut has been tested in Lake Constance to a depth of 105 metres (344 ft) and has a design limit of 180 metres (590 ft).
The Speleonaut was first used at the Blautopf in 1996. In 2001 Hasenmayer reached the Mörikedom ("Mörike cathedral") chamber of the Blauhöhle, which he had discovered in 1985, in the Speleonaut. In 2004 he reached a point beyond the Mörikedom 1,800 metres (5,900 ft) into the mountain. In the same year he discovered two more large chambers in the Blauhöhle: the Mittelschiff (or "nave") and the Äonendom.
- Schnabel, Ulrich (1 March 1996). "Der Mann im Blautopf" [The man in the Blautopf]. Die Zeit (in German) (10). Retrieved 26 July 2013.
- Hasenmayer, Jochen (25 March 1996). "Geologie: Auf Den Grund Gegangen" [Geology: Gone to Ground]. Focus (in German) (13). Retrieved 26 July 2013.
- "A short History of Cave Diving in Germany". Archived from the original on 23 March 2012. Retrieved 26 July 2013.
- Raabe, Kristin (12 February 2012). "Tiefenrausch - Manuskript zur Sendung" (in German). Deutschlandradio. Retrieved 26 July 2013.
- "Höhlentauchen: Manie oder Herausforderung?" [Cave Diving: Mania or Challenge?] (in German). Spiegel Online. 2003. Retrieved 26 July 2013.
- Pohl, Werner (2007). "Die wahren Abenteuer finden nicht in den Beinen statt, sondern im Kopf" ["True adventures will not be found in the legs, but in the head"] (PDF). RehaTreff (in German). Ettlingen: AWS Medienverlag (2): 27–30. Retrieved 26 July 2013.