Directory of U.S. Military Rockets and Missiles
Appendix 3: Space Vehicles
Copyright © 2024 Andreas Parsch

Boeing UFO

The UFO (UHF Follow-On) system is a series of geostationary communication satellites, commissioned in the 1990s by the U.S. Navy to supplant and eventually replace the older FLTSATCOM (Fleet Satellite Communications) and Leasat satellites. Prime contractor was Hughes Space, now Boeing Satellite Systems.

The first three UFO satellites were of Block 1 configuration, and were equipped with a UHF (Ultra-High Frequency) and an SHF (Super-High Frequency) payload. Block 2, satellites UFO-4 to -6, added an EHF (Extremely High Frequency) payload, whose capacity was doubled in the final Block 2 satellite, UFO-7. In Block 3, satellites UFO-8 to -10, the SHF system was replaced by a new Ka-band Global Broadcast Service (GBS) payload. The final satellite UFO-11 was of Block 4 configuration, with enhanced UHF and EHF payloads.

Image: Boeing
UFO Block 3

The successor to UFO is MUOS (Mobile User Objective System). In 2021, responsibility for the remaining UFO assets was transferred from the Navy to the newly-established U.S. Space Force. As of early 2024, at least 4 UFO satellites are still operational.

Name Intl. Designation Launch Notes
UFO-11993-015A25-Mar-1993Partial launch failure; satellite stranded in unusable orbit
UFO-21993-056A03-Sep-1993Also known as USA-95
UFO-31994-035A26-Apr-1994Also known as USA-104
UFO-41995-003A29-Jan-1995Also known as USA-108
UFO-51995-027A31-May-1995Also known as USA-111
UFO-61995-057A22-Oct-1995Also known as USA-114
UFO-71996-042A25-Jul-1996Also known as USA-127
UFO-81998-016A16-Mar-1998Also known as USA-138
UFO-91998-058A20-Oct-1998Also known as USA-141
UFO-101999-063A23-Nov-1999Also known as USA-146
UFO-112003-057A18-Dec-2003Also known as USA-174

Launch dates of the UFO series

Main Sources

[1] Wikipedia: UHF Follow-On Satellite
[2] Gunter Krebs: UFO 1, 2, 3, UFO 4, 5, 6, 7, UFO 8, 9, 10, UFO 11
[3] USSF: Army, Navy SATCOM Mission Areas Shifting to U.S. Space Force

Back to Directory of U.S. Military Rockets and Missiles, Appendix 3

Last Updated: 12 April 2024