This list includes major auxiliaries which support special missions and projects and general non-combat logistics requirements. Other auxiliaries are listed separately: fleet support auxiliaries, minor auxiliaries and yard craft, and research and survey ships.
Ships not yet commissioned, or in long-term overhaul/conversion, are listed in italics. Navigation and surface-search radars are not listed. All classifications are purely unofficial and are based on an attempt to use standard classifications throughout all navies; they may or may not correspond to "official" designations. Where two dates are given (i.e. 1965/82), the first is the date of initial completion, and the second is the date of acquisition, conversion, or transfer. Designations given in (parentheses) are assigned but not displayed on the ship's hull.
Ships operated by MSC carry the prefix "USNS" with their names; chartered ships are M/V.
Observation Island
(C4-S-1A "Mariner" type) missile tracking ship
Concept/Program: A former cargo ship converted to a missile test ship, then converted as a missile tracking ship, primarily to monitor Soviet missile tests. Was completed for merchant service 1954, converted to missile test ship (YAG 57/EAG 154/AG 154) 1956-1958; converted to missile tracking configuration 1979-1981. Retains merchant configuration but with extensive antenna arrays added, superstructure enlarged, kingposts removed. Now operated by MSC with a civilian crew under USAF operational control.
Builders: New York SB, Camden, NJ; missile tracking conversion at Maryland SB&DD, Baltimore.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AGM 23) | Observation Island | 1954/81 | PAC | (none) | MSC Pacific |
Zeus
cable ship
Concept/Program: The Navy's last cable ship; civilian-manned under MSC. The only purpose-built USN cable ship ever. Most cable laying and repair operations are now handled by civilian contractors.
Builders: NASSCO, San Diego.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-ARC 7) | Zeus | 1984 | ATL | (none) | MSC Atlantic |
Waters
navigation research & missile tracking ship
Concept/Program: A large survey ship built to replace the venerable Mizar (T-AGOR 11), but lack of operating funds has forced conversion to other roles. Originally had extensive search/survey gear, facilties for ROVs, and a "moon pool"; these facilities have apparently been deleted. She is now fitted with equipment from Vanguard and Range Sentinel to fill navigation research and missile tracking roles. Ship is now under sponsorship of the Strategic Programs Office. The ship should properly be re-designated in the T-AGM or T-AG series.
Builders: Avondale Industries, New Orleans; conversion by NORSHIPCO, Norfolk, VA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AGS 45) | Waters | 1993/98 | ATL | Port Canaveral | MSC Atlantic |
Concept/Program: A Spruance-class destroyer to be decommissioned 3/2003 will be converted into a self defense trials ship, to replace the ex-Decatur. Will be remote-controlled while in operation; full extent of the conversion is not known.
Builders: Litton/Ingalls SB, Pascagoula, MS.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| DD 964 | Paul F. Foster | 1976/04 | PAC | San Bruno, CA | Pending Conversion |
Concept/Program: A Spruance-class destroyer to be decommissioned 3/2003 will be loaned to Northrop Grumman (Ingalls) as a testbed for the DD(X) class destroyers. This will be a major conversion, involving a completely new superstruture, new propulsion, new electronics, etc.
Builders: Litton/Ingalls SB, Pascagoula, MS.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| DD 968 | Arthur W. Radford | 1977/05? | ATL | Pascagoula? | Pending Conversion |
Hayes
acoustic trials ship
Concept/Program: A former oceanographic research ship (ex-AGOR 16) which has been extensively converted to serve as an acoustic trials ship, operating in support of submarine noise trials. The ship is a catameran; she was unsuccessful as an AGOR due to poor seakeeping. Conversion included major changes to superstructure and an entirely new propulsion system to provide ultra-quiet operation. The ship is operated by MSC for David Taylor Naval Research Center.
Builders: Todd Shipyards, Seattle, WA; conversion by Puget Sound Naval Shipyard, Bremerton, WA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AG 195) | Hayes | 1971/92 | ATL | Port Canaveral | MSC Atlantic |
ex-Decatur
(Forrest Sherman class) weapons trials ship
Concept/Program: An old destroyer converted to serve as a trials ship for integrated ship self-defense systems. She is used to test Sea Sparrow, RAM and Phalanx systems against live missile attacks. For this role the ship has been refitted with all-new masts, a modified superstructure, diesel propulsion, and a small helicopter platform; the vessel is unmanned and remotely controlled while firing trials are carried out. Additional weapons and combat systems may be tested in the future; expected to remain in operation in this role through 2010. The ship is the former Decatur (DDG 31, nee DD 936); she was stricken 1989 but was retained for this role. Is not assigned any official designation or name, but carries the number "31" on her bow and is generally known as Decatur. Will be replaced by Paul F. Foster in 2004.
Builders: Bethlehem Steel, Quincy MA; conversion by Puget Sound Naval Shipyard, Bremerton, WA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | ex-Decatur | 1956/94 | PAC | San Bruno, CA |
Invincible
(modified Stalwart class) missile tracking ship
Concept/Program: Former SURTASS ocean surveillance ship converted to a missile tracking ship, employed in support of USAF programs. Had been deactivated in 1995 and stricken, but reactivated in 1998 and converted; not redesignated T-AGM 24 until 4/2000. Despite this redesignation, she is officially listed as "stricken" by the US Navy. Carries the radar array in a dome aft, and the stern area has been built up to provide additional equipment space. Under USAF operational control.
Builders: Tacoma Boatbuilding, WA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AGM 24) | Invincible | 1986/98 | PAC | (none) | MSC Central |
Stalwart
class air surveillance patrol ships (2 ships)
Concept/Program: Former ocean surveillance (sonar) ships outfitted with air search radars and employed to track drug-running aircraft in the Gulf of Mexico. Modifications for this role are minimal; the sonars have been removed and the radar is installed at the masthead, in place of the original satellite antenna. Two sisters served with USCG in a similar role, but are now deactivated.
Builders: Tacoma Boatbuilding, WA, except AGOS 16 by Trinity/Halter Marine, New Orleans, LA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AGOS 1) | Stalwart | 1984/93 | ATL | (none) | MSC Atlantic | |
| (T-AGOS 16) | Capable | 1989/93 | ATL | (none) | MSC Atlantic |
C-Commando
special operations submersible support ship
Concept/Program: Former oilfield support tug chartered to support testing of the new Advanced SEAL Delivery System mini-subs.
Builders: ??
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | C-Commando | 19??/00 | PAC | Pearl Harbor | MSC Pacific |
Carolyn Chouest
submarine/submersible support ship
Concept/Program: A former oilfield support tug chartered as a support ship for nuclear submersible NR-1; also used for general submarine escort and rescue, trials support, etc. Equipped to operate ROVs.
Builders: North American SB, Larose, LA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | Carolyn Chouest | 1977/94 | ATL | Groton | MSC Atlantic |
Kellie Chouest
submersible support and submarine rescue ship
Concept/Program: New-construction oilfield support tug-type vessel chartered to serve in a submarine/submersible support role. Equipped to operate ROVs and unmanned submersibles, DSRVs, and the submarine rescue chamber; also supports submarine trials. Has a stern lift for the DSRVs.
Builders: North American SB, Galliano, LA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | Kellie Chouest | 1996 | PAC | San Diego | MSC Pacific |
Dolores Chouest
submersible support and submarine rescue ship
Concept/Program: Former oilfield support tug chartered and converted to serve in a submarine/submersible support role. Equipped to operate ROVs and unmanned submersibles, DSRVs, and the submarine rescue chamber; also supports submarine trials. Has a stern lift for the DSRVs.
Builders: North American SB, Galliano, LA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | Delores Chouest | 1978/?? | ATL | Norfolk | MSC Atlantic |
Joint Venture high speed experimental ship
Concept/Program: A chartered commercial high-speed catamaran, used to test various new concepts, both for warships and for logistics/sealift ships. Has been assigned to the Army, Coast Guard, and Navy at various times, and has been used operationally in the Middle East/Indian Ocean areas. Is assigned Navy designation IX 532, but carries builder's designation HSV-X1 on the hull.
Builders: Incat Ltd, Australia.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (IX 532) HSV-X1 |
Joint Venture | 1998/01 |
Mercy
class hospital ships (2 ships)
Concept/Program: Former tankers extensively converted to large hospital ships to support US rapid-deployment forces; also can support disaster-relief and refugee operations. These vessels are in the Ready Reserve Force and are maintained in 5-day readiness; they are civilian-manned. They have extensive hospital facilities, including 12 operating rooms, 4 X-ray rooms, pharmacy, blood bank, 80-bed intensive care, 920 general beds, plus surge capacity of 1000 additional patients for limited care; there is a large flight deck for helicopter operations.
Builders: Construction and conversion by NASSCO, San Diego, CA.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AH 19) | Mercy | 1976/86 | PAC | San Diego | MSC Pacific | RRF-5 |
| (T-AH 20) | Comfort | 1976/87 | ATL | Baltimore | MSC Atlantic | RRF-5 |
Gus W. Darnell
class (T5 type) transport tankers (5 ships)
Concept/Program: Transport tankers built for general military sealift duties. Two are fitted with limited alongside UNREP facilities, and all are fitted for astern refueling. Operated by MSC in common-user sealift service.
Builders: American SB, Tampa, FL.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AOT 1121) | Gus W. Darnell | 1985 | ATL | (none) | MSC Atlantic | |
| (T-AOT 1122) | Paul Buck | 1985 | PAC | (none) | MSC Pacific | |
| (T-AOT 1123) | Samuel L. Cobb | 1985 | PAC | (none) | MSC Pacific | |
| (T-AOT 1124) | Richard G. Matthiesen | 1986 | PAC | (none) | MSC Far East | |
| (T-AOT 1125) | Lawrence H. Gianella | 1986 | ATL | (none) | MSC Europe |
Green Wave
polar logistics ship
Program/Concept: German-built container ship chartered for resupply of Arctic and Antarctic bases.
Builders: Howaldswerke, Kiel, Germany
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (T-AK 2050) | Green Wave | 1980/84 | PAC | (none) | MSC Far East |
Sagamore
general logistics ship
Program/Concept: A commercial, self-loading container ship chartered for general logistics duties.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| Sagamore |
Concept/Program: Small commercial tanker chartered for fuel transport duties in the Western Pacific.
Builders: Tuzla Gemi Endustrisi, Tuzla, Turkey.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| (none) | Montauk | 1999/00 | PAC | (none) | MSC Far East |
Strong Texan
special logistics ship
Concept/Program: A highly specialized cargo ship designed for transporting bulky and/or extremely heavy cargo; fitted with two 160-ton booms, RO/RO vehicle capability, and limited float-on/float-off capability. Can carry 225 TEU as a container ship.
Builders: Arnhemsche Scipswerf Maats, Arnhem, Netherlands.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | Strong Texan | 1976/?? | PAC | (none) | MSC Pacific |
Westpac Express
high speed sealift ship
Concept/Program: A chartered commercial high-speed catamaran, used to transport Marines between Okinawa and Japan. Unlike HSV-X1, this is an operational logistics ship, not an experimental ship.
Builders: Austal Ltd, Australia.
| Number | Name | Year | FLT | Homeport | Group | Notes |
| -- | Westpac Express | 2001 | PAC | Okinawa |