A series of maneuvers which a submarine crew exercises to prove their readiness for sea. The intent is to verify proper stowage of all items. Shortly after deployment, once a submarine has reached deep water, this exercise is performed and the sub repeatedly dives and rises at increasingly steeper angles. If an item is improperly stowed it will shift (or dangle) and generate noise. Since silence is of utmost importance during a submarine's mission these maneuvers are often performed during inspections to show high ranking officers that the crew has the appropriate concern for the Ship's mission. On rare occasions these maneuvers are performed for spectators (or riders), and in this case they serve a dual purpose; still proving a ships readiness for sea, but also demonstrating the capabilities of these magnificent warships.
Pot and pans, in the ship's galley, could be heard clanking by sonar during angles and dangles, indicating that the cooks were not properly prepared for a silent mission.