GPS IIR-11: The Backbone of Global Navigation
GPS IIR-11, also known as USA-178, is a satellite that forms part of the Global Positioning System (GPS), which provides critical navigation services worldwide. Launched on 31 March 2003, it is one of the Block IIR satellites, designed to enhance the accuracy, reliability, and coverage of the GPS co
| Active satellites | 15,786 |
| Catalogued objects | 31,473 |
| Starlink active | 10,063 |
What is GPS IIR-11?
GPS IIR-11, also known as USA-178, is a satellite that forms part of the Global Positioning System (GPS), which provides critical navigation services worldwide. Launched on 31 March 2003, it is one of the Block IIR satellites, designed to enhance the accuracy, reliability, and coverage of the GPS constellation. The satellite, with NORAD ID 27663, was built by Lockheed Martin and is operated by the United States Space Force.
Mission and Purpose
The primary mission of GPS IIR-11 is to transmit precise timing and positioning data to GPS receivers on Earth. This satellite plays a crucial role in navigation for military, civil, and commercial applications. The GPS constellation, including GPS IIR-11, provides continuous navigation data that is essential for activities ranging from aviation and maritime operations to smartphone navigation and financial transactions.
Orbital Characteristics
GPS IIR-11 orbits the Earth in a medium Earth orbit (MEO) at an altitude of approximately 20,200 kilometres. It follows an inclination of 55 degrees, which allows it to cover a wide swath of the Earth's surface. The satellite completes an orbit roughly every 12 hours, ensuring consistent global coverage. These orbital parameters are typical for GPS satellites, designed to maintain a stable and predictable path.
Significance and Legacy
GPS IIR-11 is part of a long legacy of GPS satellites that have transformed global navigation since the first satellite was launched in 1978. The Block IIR series, to which GPS IIR-11 belongs, introduced improvements such as increased signal accuracy and enhanced encryption for military use. The satellite's contributions to navigation and timing have been pivotal in advancing technology and supporting a wide range of industries.
Current Status
As of the latest data, GPS IIR-11 remains operational and continues to serve as a vital component of the GPS constellation. With 15,786 active satellites in orbit, GPS IIR-11 is part of a select group that supports critical infrastructure and services. Its status and operational details can be explored further in Orbital Radar's Satellite Library, where it is catalogued alongside other GPS satellites.
📎 Cite this article · data available
Orbital Radar Newsroom. (2026). GPS IIR-11: The Backbone of Global Navigation. Orbital Radar. https://orbitalradar.com/blog/gps-iir-11-global-navigation"GPS IIR-11: The Backbone of Global Navigation." Orbital Radar, 12 October 2026, https://orbitalradar.com/blog/gps-iir-11-global-navigation.@misc{orbitalradar_gps_iir_11_global_navigation,
title = {GPS IIR-11: The Backbone of Global Navigation},
author = {{Orbital Radar}},
year = {2026},
howpublished = {\url{https://orbitalradar.com/blog/gps-iir-11-global-navigation}}
}
