Editing Hull classification symbol (section)

=== National Oceanic and Atmospheric Administration ===
The [[National Oceanic and Atmospheric Administration]] (NOAA), a component of the [[United States Department of Commerce]], includes the [[National Oceanic and Atmospheric Administration Commissioned Officer Corps]] (or "NOAA Corps"), one of the eight [[uniformed services of the United States]], and operates a fleet of seagoing research and survey ships. The [[NOAA ships and aircraft|NOAA fleet]] also uses a hull classification symbol system, which it also calls "hull numbers," for its ships.

After NOAA took over the former fleets of the U.S. Coast and Geodetic Survey and the U.S. Fish and Wildlife Service Bureau of Commercial Fisheries in 1970, it initially retained the Coast and Geodetic Survey's hull-number designations for its [[survey ship]]s and adopted hull numbers beginning with "FRV", for "Fisheries Research Vessel", for its [[Fishery|fisheries]] [[research ship]]s. It later adopted a new system of ship classification, which it still uses today. In its modern system, the NOAA fleet is divided into two broad categories, research ships and survey ships. The research ships, which include [[Oceanography|oceanographic]] and fisheries research vessels, are given hull numbers beginning with "R", while the survey ships, generally [[hydrography|hydrographic]] survey vessels, receive hull numbers beginning with "S". The letter is followed by a three-digit number; the first digit indicates the NOAA "class" (i.e., size) of the vessel, which NOAA assigns based on the ship's [[gross ton]]nage and [[horsepower]], while the next two digits combine with the first digit to create a unique three-digit identifying number for the ship.

Generally, each NOAA hull number is written with a space between the letter and the three-digit number, as in, for example, {{ship|NOAAS|Nancy Foster|R 352}} or {{ship|NOAAS|Thomas Jefferson|S 222}}.<ref>Wertheim, ''The Naval Institute Guide to Combat Fleets of the World, 15th Edition: Their Ships, Aircraft, and Systems'', p. 1005.</ref>

Unlike in the U.S. Navy system, once an older NOAA ship leaves service, a newer one can be given the same hull number; for example, "S 222" was assigned to {{ship|NOAAS|Mount Mitchell|S 222}}, then assigned to NOAAS ''Thomas Jefferson'' (S 222), which entered NOAA service after ''Mount Mitchell'' was stricken.