What does it mean to conn a ship?

Answer 1

Conning (controlling) is a reference to the Conn or Bridge officer of a ship or submarine, or the Control Deck of the vessel. The Conn officer is in charge of directing all on-watch operations of the vessel, be it normal navigation, shipboard housekeeping, regular transit/patrol, or target tracking operations. During battlestations, the Conn officer duty generally shifts to the Commanding Officer.

On surface ships, the Conn is located on the main bridge of the vessel. For submarines, it shifts between the Control room (submerged) or the Bridge, which is at the top of the sail (surfaced transit). In the earlier days of submarine warfare, the sail was called the Conning Tower, as this was the area above the Control Room where the CO would literally Conn the ship from during attacks on the surface or while submerged.

During transits into and out of ports, the Conn officer still controls the ship, but follows commands from a civilian harbor pilot (who boards prior to harbor entry), who has navigational authority over any vessel under his charge when entering his/her assigned port or waterway. The is due to the fact that harbor/river pilots are more keenly aware of the constant changes in waterway conditions than CO's and Navigators of boats that may only visit occasionally, or boats that have been on deployment from their homeport for several weeks or months.