Green Mountain State.jpg
SS Green Mountain State (T-ACS-9)
United States
Name: SS Green Mountain State (T-ACS-9)
Builder: Ingalls Shipbuilding Inc., Pascagoula, Mississippi
Laid down: 2 December 1963
Launched: 20 August 1964
Acquired: 15 March 1992
Out of service: 28 July 2006
Status: National Defense Reserve Fleet - Logistical Support
Notes: Launched as SS Mormacaltair
General characteristics
Class and type: Keystone State-class crane ship
Displacement: 31,500 tons
Length: 668 ft 5 in (203.73 m)
Beam: 76 ft 1 in (23.19 m)
Draft: 33 ft 6 in (10.21 m)
Propulsion: two General Electric turbines two boilers single propeller, 19,250shp
Speed: 17 kn (20 mph; 31 km/h)
Capacity: 300+ Cargo Containers

Full Operational Status: 89 civilian mariners

Reduced Operational Status: 10 civilian mariners
Armament: None
Aviation facilities: None

SS Green Mountain State (T-ACS-9) is a crane ship in ready reserve for the United States Navy. The ship was named for the state of Vermont, which is also known as the Green Mountain State.


Green Mountain State was laid down on 2 December 1963 as the break-bulk freighter SS Mormacaltair, ON 298129, IMO 6421347, a Maritime Administration type (C6-S-60a) hull, under MARAD contract (MA 143). Built by Ingalls Shipbuilding at Pascagoula, Mississippi (hull no. 486), she was launched on 20 August 1964 and delivered to MARAD 26 March 1965, for service with Moore-McCormack Lines. In 1975 the ship was lengthened and converted to a partial container ship by Todd Ship Yard, Galveston, Texas. She was sold to United States Lines in 1983 and renamed SS American Altair. US Lines ceased operations in 1986 and the ship was turned over to MARAD in 1987 and placed in the National Defense Reserve Fleet (NDRF). The ship was converted to a MARAD hull type (C6-S-MA60d) Crane Ship at National Steel and Shipbuilding Co., San Diego, California, and placed in service as SS Green Mountain State (T-ACS-9) on 15 March 1992, assigned to the Ready Reserve Force (RRF), under operation control of Military Sealift Command (MSC).[1]

Mothballed in Suisun Bay, 2011.

Green Mountain State was berthed at Bremerton, Washington, where she was maintained in a five-day readiness status, assigned to Maritime Prepositioning Ship Squadron Three. She was removed from MSC control and withdrawn from the RRF by reassignment to the National Defense Reserve Fleet (Beaumont, Texas) on 28 July 2006. She has since been reassigned to the Suisun Bay Reserve Fleet.[citation needed]



  1. ^ Silverstone 2011, p. 237


  • Silverstone, Paul (2011). The Navy of the Nuclear Age, 1947-2007. Routledge. ISBN 1135864667.


  • SS Green Mountain State (T-ACS-9)
  • This article includes information collected from the Naval Vessel Register, which, as a U.S. government publication, is in the public domain. The entry can be found here.

External links

  • National Defense Reserve Fleet Inventory