An officer of the deck (OOD) is a watchstanding position in a ship's crew in the United States Navy, United States Coast Guard, and NOAA Commissioned Officer Corps who is tasked with certain duties and responsibilities for the ship. The officer of the deck is the direct representative of the ship's commanding officer and is responsible for the ship.
In port, the OOD is stationed on the quarterdeck, which is the entry point to the ship. All personnel and visitors must cross the quarterdeck to enter the ship. It is a ceremonial space, representing the ship to visitors. In addition, the OOD has a qualified petty officer manning the gangplank, called the petty officer of the watch (POOW). The POOW is in the position of managing who comes and goes, as well as security. On larger ships there may be as many as three gangplanks in use at once.
At sea, the officer of the deck is stationed on the bridge and is in charge of navigation and safety of the ship, unless relieved by the captain or a senior qualified line officer. The officer of the deck is assisted by the junior officer of the deck, who is in the process of qualifying as full officer of the deck, and the conning officer, who is also training to become an OOD, but is directly responsible for the maneuvering of the ship. The officer of the deck is also assisted by a boatswain's mate of the watch (BMOW), quartermaster of the watch (QMOW), and signalman of the watch (SMOW).
The following is a list of the OOD's primary duties as prescribed by the Standard Organization and Regulations of the United States Navy, OPNAVINST 3120.32
There is also a very formal method for relieving the officer of the deck.
Assume that Lieutenant Smith is the officer of the deck and Lieutenant Doe is his replacement. Lieutenant Doe will check into the Combat Information Center (CIC) to determine any necessary actions that will be expected to occur during the watch, check the navigational track, read any orders, and determine the position of all nearby ships. After this is complete, Lieutenant Doe will state to Lieutenant Smith, "I am ready to relieve you, sir." Lieutenant Smith states, "I am ready to be relieved." He will then brief Lieutenant Doe on any additional information that the replacement should be made aware of, reconfirming the information that Lieutenant Doe has previously gained on his own. When Lieutenant Doe is fully satisfied, he then states, "I relieve you, sir." Lieutenant Smith then states, "I stand relieved. Attention in the pilot house (or bridge), Lieutenant Doe has the deck." An exchange of hand salutes would also be appropriate, depending on the ship. Lieutenant Doe would then announce, "This is Lieutenant Doe, I have the deck." (The use of the term sir in the manner indicated occurs without regard to the actual ranks held by the officers.)
Typically, the junior officer of the deck has the conn, (i.e., control of the engines and rudder). The junior officer of the deck is relieved in a similar manner. The deck and or the conn may be assumed by the captain, simply by announcing the fact or by issuing an order to the helmsman or lee helmsman. For example, the captain may state, "I have the deck and the conn," or "I have the conn," or "Right full rudder, all ahead flank." In the latter case, someone (ordinarily the junior officer of the deck) in the pilot house (or bridge) will announce, "The captain has the conn." The conn may also be passed to someone else, for a particular purpose. While the captain may assume the conn, the officer of the deck may order the junior officer of the deck to pass him the conn, "Ensign Pulver, pass me the conn." Ensign Pulver will then state, "This is Ensign Pulver, Lieutenant Doe has the deck and the conn." Lieutenant Doe then announces, "This is Lieutenant Doe, I have the deck and the conn." In an emergency, the officer of the deck can, if he so chooses, assume the conn by announcing, for example, "This is Lieutenant Doe, I have the conn. Hard right rudder, all engines ahead flank." However, in most ships, during normal underway operations, it is generally considered "poor form" to request the JOOD to pass the conn, as a good OOD would be expected to direct the JOOD without the necessity of assuming the conn himself. Thus, the distinction between having the "deck" and having the "conn" remains.
These changes in status are marked down in the ship's log.