HMS Otus (S18)

HMS Otus was a Royal Navy Oberon-class submarine launched in 1962. She was decommissioned in the early 1990s and is now a naval museum in Germany.

Construction
Built in 1962 at Scotts Yard in Greenock, Scotland, the sub's trials were conducted in Scottish waters, mainly Loch Long and Loch Fyne. Her pennant number (S18) was carried in white paint on the ship's conning tower fin, however this was removed in 1964 as a discontinued practice.

Royal Navy service
The first commission of Otus included large-scale missile trial exercises in the Atlantic Ocean and visits to the United States and Halifax, Canada.

Otus attended the 1977 Silver Jubilee Fleet Review off Spithead when she was part of the Submarine Flotilla.

Deep escape trials
In July 1987, a team of British, Commonwealth and international submariners took part in trials in Bjornafjorden, near Bergen, Norway, aboard Otus. They ran a series of progressively deeper escapes, starting at 30 m. At 90 m, individuals started to drop out. At the end of the trials two submariners reached a depth of 183 m. This set a new world record which to date has not been broken. Of the two record breakers, the first (the commander of the Submarine Escape Training Tower at HMS Dolphin) was a regular ascent under control. The second, a petty officer instructor from the Submarine Escape Training Tower suffered an emergency release having given the alarm signal whilst flooding up the chamber. It was considered safer and quicker to escape him rather than depressurise and drain down. Both escapees suffered no lasting effects and returned to normal service. Both received military honours of the British Empire in the following years for this act.

Decommissioning and museum
Otus was decommissioned in the early 1990s and resided at Pound's scrapyard in Portsmouth for several years. She was later purchased by a German entrepreneur, who moored her in the harbour of the town of Sassnitz on the island of Rügen in Germany to act as a floating naval museum.