Definition
USA‑96, also designated GPS IIA‑14, GPS II‑23 and GPS SVN‑34, was an American navigation satellite that formed part of the United States Department of Defense’s Global Positioning System (GPS). It was the fourteenth of the nineteen Block IIA GPS satellites to be launched and the final one of that generation to be retired.
Overview
The satellite was launched on 26 October 1993 at 17:04 UTC aboard a Delta II 7925‑9.5 launch vehicle (flight D223) from Cape Canaveral Air Force Station Launch Complex 17B. Operated by the U.S. Air Force, USA‑96 entered service on 25 November 1993 and remained active, with brief interruptions, until it was placed in reserve on 9 October 2019 and formally retired on 13 April 2020. Throughout its operational life the spacecraft transmitted the PRN 04 and later PRN 18 signals, serving as an on‑orbit spare in the GPS constellation.
Etymology / Origin
The “USA” designation is part of a numbering scheme used by the United States Air Force to catalog military spacecraft launched since 1984, where each satellite receives a sequential identifier prefixed by “USA”. The numerical suffix “96” indicates that it was the ninety‑sixth object assigned a USA designation. The alternative names (GPS IIA‑14, GPS II‑23, GPS SVN‑34) reflect its placement within the GPS program: Block IIA was the second generation of operational GPS satellites, and “SVN‑34” denotes its Space Vehicle Number within the GPS fleet.
Characteristics
| Parameter | Details |
|---|---|
| Spacecraft type | GPS Block IIA |
| Manufacturer | Rockwell International (Rockwell Space Systems) |
| Launch mass | 840 kg (1,850 lb) |
| Dimensions | 5.3 m (≈ 17 ft) across with solar panels deployed |
| Power supply | 710 W from dual solar arrays |
| Design life | 7.5 years (planned) |
| Actual operational duration | ~26 years (1993–2019) |
| Orbit | Medium Earth orbit, semi‑synchronous; perigee 20 107 km, apogee 20 264 km, inclination 55.08°, orbital period 718 minutes |
| Slot in constellation | Initially slot 4, plane D; later operated from slot 6, plane D |
| Payload | Two L‑band navigation signals (L1 1575.42 MHz, L2 1227.60 MHz), four atomic clocks (2 rubidium, 2 cesium), nuclear detonation detection sensors |
| End‑of‑life disposition | Moved to a graveyard orbit and deactivated |
Related Topics
- Global Positioning System (GPS) – the worldwide satellite navigation system of which USA‑96 was a component.
- GPS Block IIA – the second generation of operational GPS satellites, of which USA‑96 was the last to be retired.
- USA‑series satellites – the broader catalog of U.S. military spacecraft identified by the “USA‑###” designation.
- Delta II launch vehicle – the expendable rocket family used to place USA‑96 into orbit.
- Navigation satellites – a class of spacecraft providing positioning, navigation, and timing services.
All information presented is derived from publicly available sources, including the United States Naval Space Command and the Wikipedia entry for USA‑96.