Description
Missile range instrumentation, navigation test support ships provide platforms for monitoring foreign missile launchers for SALT Treaty verification and supporting submarine navigation system testing and ballistic missile flight tests.

Features
USNS Observation Island operates worldwide, monitoring compliance with strategic arms treaties and supporting U.S. military weapons test programs. USNS Invincible provides a platform for a dual-band radar developed by the U.S. Air Force to support its collection requirements against theater ballistic missiles. USNS Waters, supports submarine navigation system testing and provides ballistic missile flight test support services.

Background
USNS Observation Island was built as a "Mariner" class merchant ship; launched Aug. 15, 1953; acquired by the Navy on Sept. 10, 1956, for use as a Fleet Ballistic Missile test ship. The vessel was converted at Norfolk Naval Shipyard. In reserve from September 1972. On Aug. 18, 1977, Observation Island was reacquired by the U.S. Navy from the Maritime Administration and transferred to Military Sealift Command and reclassified as T-AGM 23. USNS Invincible is a converted Stalwart-class T-AGOS ship. USNS Waters delivered in 1993 as an oceanographic survey ship. She was converted in 1998 under the sponsorship of the Strategic Systems Program Office. Waters began operations in 1999, replacing USNS Vanguard (deactivated in 1998) and USNS Range Sentinel (deactivated in 1997).

General Characteristics, Observation Island Class

Builder: New York Shipbuilding; Conversion: Maryland Shipbuilding and Drydock Corporation.
Propulsion: Two boilers; 1 GE turbine; 19,250 hp (14.36 MW); 1 shaft.
Length: 564 feet (171.6 meters).
Beam: 76 feet (23.2 meters).
Displacement: 17,015 tons (17,288.06 metric tons) full load.
Speed: 20 kts (23 mph).
Crew: 66 civilians, 59 technicians.
Homeport: No homeport assigned.
Ships:
USNS Observation Island (T-AGM 23)

General Characteristics, Invincible Class

Builder: Tacoma Boatbuilding, Tacoma, WA.
Propulsion: four diesel generators, two shafts, 1,600 bhp.
Length: 224 feet (68.28 meters).
Beam: 43 feet (13.11 meters).
Displacement: 2,285 tons (2321.56 metric tons) full load.
Speed: 11 knots (12.67 mph).
Crew: 18 civilians, 11 technicians.
Homeport: No homeport assigned.
Ships:
USNS Invincible (T-AGM 24)

General Characteristics, Waters Class

Builder: Avondale Industries, New Orleans, LA; Conversion yard: Norfolk Shipbuilding & Drydock Corp., Norfolk, VA.
Propulsion: Diesel-electric, twin-screw, 7,400 shp.
Length: 457 feet (139.29 meters).
Beam: 69 feet (21.03 meters).
Displacement: 12,208 tons (12,403.33 metric tons) full load.
Speed: 13 knots (14.96 mph).
Crew: 32 civilians, 59 technicians.
Homeport: No homeport assigned.
Ships:
USNS Waters (T-AGS 45)