[2] Propulsion machinery consisted of 2 Admiralty Standard Range 16 VTS diesel generators, and two 3,000-shaft-horsepower (2,200 kW) electric motors, each driving a 7-foot diameter (2.1 m) 3-bladed propeller at up to 400 rpm.

[2] The first commission of Otus included large-scale missile trial exercises in the Atlantic Ocean and visits to the United States and Halifax, Nova Scotia, Canada.

[3] In July 1987, a team of British, Commonwealth and international submariners took part in trials in Bjornafjorden, near Bergen, Norway, aboard Otus.

Norman Cook MBE, the commander of the Submarine Escape Training Tower at HMS Dolphin) was a regular ascent under control.

Hamish Jones BEM) from the Submarine Escape Training Tower, suffered an emergency release having given the alarm signal whilst flooding up the chamber.

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 museum ship.