# Delta G

> American expendable launch vehicle

**Wikidata**: [Q49537](https://www.wikidata.org/wiki/Q49537)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Delta_G)  
**Source**: https://4ort.xyz/entity/delta-g

## Summary  
Delta G (also called Thor‑Delta G) is an American expendable launch vehicle that belongs to the Thor‑Delta family of rockets. Its first flight took place on 14 December 1966, and it was derived from the earlier Delta E launch system.

## Key Facts  
- **First flight:** 14 December 1966 (UTC)【source】  
- **Country of origin:** United States【source】  
- **Vehicle class:** Expendable launch vehicle; subclass of the Thor‑Delta family【source】  
- **Based on:** The Delta E launch vehicle【source】  
- **Alias:** Thor‑Delta G【source】  
- **Instance of:** Rocket model (Wikidata classification)【source】  
- **Related missions:** Associated with the U.S. biosatellite program (Biosatellite 1 and Biosatellite 2)【source】  
- **Image:** ![Delta G](https://commons.wikimedia.org/wiki/Special:FilePath/Delta_G.jpg)【source】  

## FAQs  
### Q: What was the purpose of the Delta G launch vehicle?  
A: Delta G was built as an expendable launch system for U.S. scientific payloads, notably supporting early biosatellite missions that studied life in space.  

### Q: When did Delta G first fly?  
A: Its maiden flight occurred on 14 December 1966.  

### Q: How does Delta G relate to the Thor‑Delta family?  
A: Delta G is a direct descendant of the Thor‑Delta series, classified as a subclass of Thor‑Delta and derived from the earlier Delta E vehicle.  

## Why It Matters  
Delta G represents a pivotal step in the evolution of United States launch capabilities during the 1960s. As part of the Thor‑Delta lineage, it helped bridge the gap between early ballistic missiles and more sophisticated orbital launchers. By adapting the proven Delta E design, Delta G provided a reliable, expendable platform for scientific payloads, including the pioneering Biosatellite missions that explored the effects of microgravity on living organisms. These experiments laid foundational knowledge for later human spaceflight and life‑science research. Moreover, Delta G’s successful 1966 launch demonstrated the viability of modular rocket families, influencing subsequent designs that would eventually lead to the modern Delta series and other commercial launch vehicles. Its legacy underscores the importance of incremental engineering advances in building a robust space launch infrastructure.  

## Notable For  
- First flight on 14 December 1966, marking its entry into the U.S. launch roster.  
- Direct derivation from the Delta E vehicle, showcasing modular reuse of proven technology.  
- Membership in the Thor‑Delta family, a cornerstone of early American expendable launch systems.  
- Association with the Biosatellite 1 and Biosatellite 2 missions, early U.S. life‑science experiments in orbit.  
- Known by the alternate name Thor‑Delta G, reflecting its heritage from the Thor missile program.  

## Body  

### Design and Heritage  
- **Family:** Delta G is a subclass of the Thor‑Delta launch system, itself derived from the Thor intermediate‑range ballistic missile.  
- **Derivation:** It was built on the Delta E architecture, inheriting its stage configuration and propulsion hardware.  
- **Alias:** The vehicle is also referred to as Thor‑Delta G, emphasizing its dual lineage from Thor and Delta technologies.  

### Operational History  
- **First Launch:** Conducted on 14 December 1966, the maiden flight carried a scientific payload for the United States.  
- **Mission Profile:** While specific payloads are not listed, the vehicle is linked to the Biosatellite program, indicating its role in launching bioscience satellites.  

### Technical Characteristics  
- **Type:** Expendable launch vehicle; all stages are discarded after use.  
- **Classification:** Recognized in Wikidata as a “rocket model” and categorized under “American expendable launch vehicle.”  

### Legacy  
- **Impact on Spaceflight:** Delta G contributed to the early development of reliable, modular launch vehicles that could be adapted for a variety of missions.  
- **Influence:** Its design principles informed later Delta variants, helping to establish a family of rockets that served both government and commercial customers for decades.  

### Related Entities  
- **Delta E:** Predecessor launch vehicle that provided the technical basis for Delta G.  
- **Biosatellite 1 & 2:** U.S. satellites focused on biological experiments; Delta G is listed as related to these missions, indicating its involvement in the biosatellite program.  

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*All information presented is drawn directly from the provided source material.*