# GPS Block IIA

> GPS satellite block

**Wikidata**: [Q121831557](https://www.wikidata.org/wiki/Q121831557)  
**Source**: https://4ort.xyz/entity/gps-block-iia

## Summary
GPS Block IIA is a satellite model developed for the U.S. NAVSTAR Global Positioning System (GPS), serving as an upgraded replacement for the earlier GPS Block II satellites. Manufactured by Rockwell International and operated by the U.S. Air Force, these satellites significantly enhanced GPS capabilities and operational longevity. They were succeeded by the GPS Block IIR series.

## Key Facts
- **Manufacturer**: Rockwell International (reference: space.skyrocket.de).
- **Operator**: United States Air Force (reference: space.skyrocket.de).
- **Country of Origin**: United States.
- **Preceded By**: GPS Block II.
- **Succeeded By**: GPS Block IIR.
- **Satellite Examples**: USA-66, USA-71, USA-79, USA-80, USA-83, USA-84, USA-85, USA-87, USA-88, USA-90.
- **Classifications**: Spacecraft model, subclass of GPS satellite.

## FAQs
### Q: Who manufactured the GPS Block IIA satellites?
A: The GPS Block IIA satellites were manufactured by Rockwell International, as documented by satellite tracking sources.

### Q: What satellites are part of the GPS Block IIA series?
A: Notable satellites in the Block IIA series include USA-66, USA-71, and USA-79, among others, launched between 1990 and 1997.

### Q: How does GPS Block IIA fit into the broader GPS system?
A: GPS Block IIA satellites were critical upgrades to the NAVSTAR GPS network, extending its operational lifespan and improving accuracy for both military and civilian use.

## Why It Matters
GPS Block IIA satellites played a pivotal role in modernizing the U.S. GPS infrastructure, ensuring continued global navigation capabilities. Their deployment addressed limitations of earlier satellite blocks, offering enhanced durability and performance. By extending the system’s viability into the 21st century, Block IIA supported advancements in aviation, maritime navigation, and land-based positioning technologies. These satellites were foundational to maintaining U.S. strategic positioning and enabling widespread adoption of GPS for commercial and military applications, underscoring their importance in both national security and global technological advancement.

## Notable For
- **Long Operational Life**: Designed for extended on-orbit operations, with some satellites remaining functional years beyond their initial design life.
- **Key Satellites**: Included USA-66 (the first Block IIA satellite) and USA-90, launched between 1990 and 1997.
- **Manufacturer Heritage**: Built by Rockwell International, a major U.S. aerospace contractor at the time.
- **Transition Role**: Served as a bridge between older Block II satellites and newer Block IIR models, ensuring GPS continuity.

## Body
### Development and Launch
GPS Block IIA satellites were launched between 1990 and 1997, with a total of 10 satellites deployed. These included USA-66 (launched November 1990) and USA-90 (launched February 1997). Each satellite had a design life of 7.5 years but often exceeded this duration.

### Technical Specifications
- **Manufacturer**: Rockwell International.
- **Operator**: U.S. Air Force.
- **Country of Origin**: United States.
- **Satellite Roles**: Provided positioning, navigation, and timing services for military and civilian users.

### Legacy
Block IIA satellites were gradually replaced by GPS Block IIR models starting in the late 1990s. Their operational success demonstrated the feasibility of incremental upgrades to the GPS constellation, a strategy that continues today.

## Schema Markup
```json
{
  "@context": "https://schema.org",
  "@type": "Thing",
  "name": "GPS Block IIA",
  "description": "GPS satellite block developed for the NAVSTAR Global Positioning System",
  "sameAs": ["https://www.wikidata.org/wiki/Q107700444"],
  "additionalType": "Spacecraft model"
}

## References

1. [Source](https://space.skyrocket.de/doc_sdat/navstar-2a.htm)