# USA-91

> American navigation satellite used for GPS

**Wikidata**: [Q7865714](https://www.wikidata.org/wiki/Q7865714)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/USA-91)  
**Source**: https://4ort.xyz/entity/usa-91

## Summary
USA-91 is an American navigation satellite launched in 1993 as part of the GPS (Global Positioning System) constellation. It was operated by the United States Air Force and manufactured by Rockwell International, using a Delta II launch vehicle.

## Key Facts
- **Class**: GPS satellite (part of the NAVSTAR Global Positioning System)
- **Operator**: United States Air Force
- **Launch Date**: May 13, 1993
- **Launch Site**: Cape Canaveral Space Launch Complex 17
- **Launch Vehicle**: Delta II (retired expendable launch system)
- **Manufacturer**: Rockwell International
- **COSPAR ID**: 1993-032A
- **Aliases**: Navstar 2A-11
- **Country of Origin**: United States

## FAQs
### Q: What was the purpose of USA-91?
A: USA-91 was a navigation satellite designed to provide precise positioning, navigation, and timing services as part of the GPS system.

### Q: Which launch vehicle was used to deploy USA-91?
A: USA-91 was launched using a Delta II rocket, part of the Delta rocket family.

### Q: Who operated USA-91?
A: The satellite was operated by the United States Air Force.

### Q: When was USA-91 launched?
A: USA-91 was launched on May 13, 1993, from Cape Canaveral Space Launch Complex 17.

### Q: What was the manufacturer of USA-91?
A: Rockwell International manufactured USA-91.

## Why It Matters
USA-91 was a critical component of the GPS constellation, which provides global positioning, navigation, and timing services. The GPS system has revolutionized navigation, enabling applications in aviation, maritime, military, and civilian use. USA-91, along with other GPS satellites, ensures continuous coverage and accuracy for users worldwide. Its successful deployment contributed to the reliability and expansion of the GPS network, supporting both military and civilian needs.

## Notable For
- **Part of the GPS Constellation**: USA-91 was one of the satellites in the NAVSTAR Global Positioning System, ensuring global coverage.
- **Delta II Launch**: The satellite was launched using the Delta II rocket, a reliable but now-retired launch system.
- **Rockwell International Manufacturing**: The satellite was built by Rockwell International, a key player in aerospace technology.
- **United States Air Force Operation**: Operated by the U.S. Air Force, reflecting its military and strategic importance.
- **Navstar 2A-11 Designation**: Known by its Navstar designation, indicating its role in the GPS network.

## Body
### Overview
USA-91 is a GPS satellite launched on May 13, 1993, as part of the NAVSTAR Global Positioning System. It was operated by the United States Air Force and manufactured by Rockwell International.

### Launch Details
- **Launch Date**: May 13, 1993
- **Launch Site**: Cape Canaveral Space Launch Complex 17
- **Launch Vehicle**: Delta II
- **COSPAR ID**: 1993-032A

### Technical Specifications
- **Manufacturer**: Rockwell International
- **Class**: GPS satellite
- **Aliases**: Navstar 2A-11

### Operational Role
- **Operator**: United States Air Force
- **Purpose**: Provided positioning, navigation, and timing services as part of the GPS constellation.

### Historical Context
- **Delta II**: The Delta II rocket was part of the Delta rocket family and was used for multiple satellite launches before being retired.
- **GPS Constellation**: USA-91 was one of the satellites in the GPS network, ensuring global coverage and accuracy.

### Significance
- **Global Navigation**: Contributed to the reliability and expansion of the GPS system, supporting both military and civilian applications.
- **Military and Civilian Use**: Enabled precise positioning for aviation, maritime, and other critical services.

## References

1. Jonathan's Space Report