Mission typeCommunications
OperatorUS Air Force
COSPAR ID2012-003A
SATCAT no.38070
Mission duration14 years
Spacecraft properties
Spacecraft typeWGS Block II
Launch mass5,987 kilograms (13,199 lb)
Start of mission
Launch date20 January 2012, 00:38 (2012-01-20UTC00:38Z) UTC
RocketDelta IV-M+(5,4) D358
Launch siteCape Canaveral SLC-37B
ContractorUnited Launch Alliance
Orbital parameters
Reference systemGeocentric

USA-233 or WGS-4 is an American military communications satellite which was launched in 2012. The fourth Wideband Global SATCOM spacecraft, it is the first WGS Block II satellite to be launched.

USA-233 can transmit data with approximately 3.6 gigabits per second bandwidth. It can point 19 individual beams at different points on the Earth, operating at x band and ka band frequencies.[1] Built by Boeing around the BSS-702 bus, the 5,987-kilogram (13,199 lb) satellite is expected to operate for 14 years. Propulsion is provided by an R-4D apogee motor, and four XIPS-25 ion thrusters for stationkeeping.[2]

The launch of USA-233 took place at 00:38 UTC on 20 January 2012, using a Delta IV-M+(5,4) carrier rocket flying from Space Launch Complex 37B at the Cape Canaveral Air Force Station.[3] The launch was conducted by United Launch Alliance, and marked the eighteenth flight of the Delta IV. The carrier rocket successfully placed the satellite into a 440-by-66,870-kilometre (270 by 41,550 mi) supersynchronous transfer orbit, with 24 degrees of inclination.[1] Upon achieving orbit, WGS-4 was assigned its USA designation, and the International Designator 2012-003A.[4] The satellite will use its onboard propulsion systems to inject itself into geosynchronous orbit.


  1. ^ a b "WGS-4 Mission Overview" (PDF). United Launch Alliance. Retrieved 20 January 2012.
  2. ^ Krebs, Gunter. "WGS 1, 2, 3, 4, 5, 6, 7, 8, 9". Gunter's Space Page. Retrieved 20 January 2012.
  3. ^ "Mission Status Center". Delta Launch Report. Spaceflight Now. 20 January 2012. Retrieved 20 January 2012.
  4. ^ McDowell, Jonathan. "Issue 653". Jonathan's Space Report. Retrieved 20 January 2012.