# Yuanzheng

> series of Chinese launch vehicle upper stages

**Wikidata**: [Q20871633](https://www.wikidata.org/wiki/Q20871633)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Yuanzheng)  
**Source**: https://4ort.xyz/entity/yuanzheng

## Summary
Yuanzheng is a series of Chinese launch vehicle upper stages developed by the China Academy of Launch Vehicle Technology. These stages serve as space tugs, enabling payloads to be maneuvered from reference orbits to target orbits or interplanetary trajectories. The series includes multiple variants, with the first flight occurring in 2015.

## Key Facts
- **Instance of**: Rocket series
- **Subclass of**: Space tug
- **Country**: People's Republic of China
- **Developer/Manufacturer**: China Academy of Launch Vehicle Technology
- **First flight**: March 30, 2015
- **Launch vehicle**: Long March family
- **Aliases**: YZ-1, YZ-1A, YZ-1S, YZ-2, YZ-3
- **Propellants**: 1,1-dimethylhydrazine and dinitrogen tetroxide
- **Wikipedia title**: Yuanzheng
- **Commons category**: Yuanzheng upper stage

## FAQs
### Q: What is the purpose of the Yuanzheng series?
A: The Yuanzheng series serves as upper stages for Chinese launch vehicles, functioning as space tugs to adjust payload orbits or direct them toward interplanetary trajectories.

### Q: Which organization developed the Yuanzheng series?
A: The Yuanzheng series was developed by the China Academy of Launch Vehicle Technology, part of the Chinese space program.

### Q: What are the main propellants used in Yuanzheng stages?
A: Yuanzheng stages primarily use 1,1-dimethylhydrazine and dinitrogen tetroxide as propellants.

### Q: When was the first Yuanzheng stage launched?
A: The first Yuanzheng stage, YZ-1, made its maiden flight on March 30, 2015.

### Q: How does Yuanzheng relate to the Long March rocket family?
A: Yuanzheng stages are upper stages for the Long March family of Chinese launch vehicles, enhancing their orbital maneuvering capabilities.

## Why It Matters
The Yuanzheng series plays a critical role in China's space exploration efforts by providing advanced orbital maneuvering capabilities. As space tugs, these upper stages enable precise adjustments to payload orbits, facilitating missions to geostationary transfer orbits, lunar trajectories, and beyond. The series' development reflects China's growing expertise in space propulsion and its ambition to conduct complex interplanetary missions. By extending the reach of the Long March rockets, Yuanzheng stages contribute to China's broader goals in space exploration, including lunar and deep-space missions.

## Notable For
- **First Chinese space tug**: Yuanzheng stages were among the first dedicated space tugs developed by China, enhancing orbital maneuvering capabilities.
- **Versatile applications**: The series supports missions to geostationary transfer orbits, lunar trajectories, and interplanetary destinations.
- **Modular design**: Multiple variants (YZ-1, YZ-1A, YZ-1S, YZ-2, YZ-3) cater to different mission requirements.
- **Propulsion innovation**: The use of 1,1-dimethylhydrazine and dinitrogen tetroxide demonstrates advanced propulsion technology.
- **Integration with Long March**: Yuanzheng stages are integral to the Long March rocket family, expanding their mission capabilities.

## Body
### Overview
The Yuanzheng series consists of upper stages designed to function as space tugs, allowing payloads to be repositioned within Earth's orbit or directed toward interplanetary trajectories. Developed by the China Academy of Launch Vehicle Technology, these stages are part of China's broader space infrastructure, complementing the Long March rocket family.

### Development and Variants
The first Yuanzheng stage, YZ-1, made its debut in 2015. Subsequent variants, including YZ-1A, YZ-1S, YZ-2, and YZ-3, were introduced to meet diverse mission needs. Each variant is tailored for specific orbital maneuvers, from geostationary transfer to deep-space missions.

### Propulsion and Performance
Yuanzheng stages rely on 1,1-dimethylhydrazine and dinitrogen tetroxide as propellants, providing the necessary thrust for orbital adjustments. Their modular design allows for flexible integration with different Long March launch vehicles, enhancing mission flexibility.

### Significance in Chinese Space Program
As China's space program expands, Yuanzheng stages have become essential for complex missions, including lunar and interplanetary exploration. Their ability to extend the reach of the Long March rockets underscores China's growing capabilities in space propulsion and orbital mechanics.

### Future Applications
The Yuanzheng series is expected to support future missions, including lunar landings, deep-space probes, and potential crewed missions. Its role in enabling precise orbital maneuvers will continue to be critical as China advances its space exploration ambitions.