# Soyuz 15

> Failed attempt to dock with Salyut 3

**Wikidata**: [Q836053](https://www.wikidata.org/wiki/Q836053)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Soyuz_15)  
**Source**: https://4ort.xyz/entity/soyuz-15

## Summary
Soyuz 15 was a Soviet space mission launched in 1974 as part of the Soyuz programme, notable for its failed attempt to dock with the Salyut 3 space station. It was the second generation of the Soyuz spacecraft (Soyuz 7K-T) and carried a two-person crew for a brief two-day mission.

## Key Facts
- **Launch Date**: August 26, 1974, from Baikonur Cosmodrome (Gagarin's Start).
- **Crew**: Gennadi Sarafanov (spacecraft commander) and Lev Dyomin (Flight Engineer 1).
- **Duration**: 48 hours and 12 minutes (173,531 seconds), completing 32 orbits.
- **Mission Objective**: Failed docking attempt with Salyut 3, a Soviet space station.
- **Spacecraft**: Soyuz 7K-T, mass 6,760 kg at takeoff.
- **Orbital Parameters**: Apoapsis 236 km, periapsis 173 km, inclination 51.62°, period 88.5 minutes.
- **Landing**: August 28, 1974, in Kazakhstan.
- **Preceded by**: Soyuz 14; **Followed by**: Soyuz 16.
- **Operator**: Soviet space program (Soviet Union).

## FAQs
### Q: What was the purpose of Soyuz 15?
A: Soyuz 15 was intended to dock with the Salyut 3 space station, but the docking attempt failed. The mission lasted only two days before returning to Earth.

### Q: Who were the crew members of Soyuz 15?
A: The crew consisted of Gennadi Sarafanov (commander) and Lev Dyomin (flight engineer).

### Q: How long did Soyuz 15 stay in orbit?
A: The mission lasted 48 hours and 12 minutes, completing 32 orbits around Earth.

### Q: What spacecraft was used for Soyuz 15?
A: Soyuz 15 used the Soyuz 7K-T, the second generation of the Soyuz spacecraft.

### Q: Where did Soyuz 15 land?
A: The spacecraft landed in Kazakhstan on August 28, 1974.

## Why It Matters
Soyuz 15 represents a critical moment in the Soviet space program, highlighting the challenges of space docking during the early era of space stations. Though the mission failed to achieve its primary objective—docking with Salyut 3—it provided valuable data for future Soyuz missions, particularly in refining rendezvous and docking procedures. The mission also demonstrated the reliability of the Soyuz 7K-T spacecraft, which became a workhorse for Soviet human spaceflight. Understanding Soyuz 15’s shortcomings helped improve subsequent missions, contributing to the long-term success of the Soyuz programme and the broader development of space station operations.

## Notable For
- **Failed Docking Attempt**: One of the few Soyuz missions that failed to dock with its target space station (Salyut 3).
- **Short Duration**: Completed in just two days, making it one of the briefest crewed Soyuz missions.
- **Second-Generation Soyuz**: Used the Soyuz 7K-T spacecraft, an upgraded version of the original Soyuz design.
- **Crew Experience**: Both crew members (Sarafanov and Dyomin) were experienced cosmonauts, with Dyomin having previously flown on Soyuz 9.
- **Orbital Precision**: Achieved a highly precise orbit (inclination 51.62°), typical of Soyuz missions targeting Salyut stations.

## Body
### Mission Overview
Soyuz 15 was launched on **August 26, 1974**, from the Baikonur Cosmodrome using a Soyuz launch vehicle. The mission was part of the Soviet Union’s efforts to develop long-duration spaceflight capabilities through the Salyut programme. The primary goal was to dock with **Salyut 3**, a military space station, but the attempt was unsuccessful.

### Spacecraft and Crew
- **Spacecraft**: Soyuz 7K-T (mass: 6,760 kg at takeoff).
- **Launch Vehicle**: Soyuz rocket.
- **Crew**:
  - **Gennadi Sarafanov** (Commander): Experienced cosmonaut.
  - **Lev Dyomin** (Flight Engineer): Veteran of Soyuz 9 (1970).
- **Call Sign**: "Dunay" (Danube).

### Orbital Details
- **Apoapsis**: 236 km.
- **Periapsis**: 173 km.
- **Inclination**: 51.62°.
- **Orbital Period**: 88.5 minutes.
- **Orbits Completed**: 32.

### Mission Timeline
- **Launch**: August 26, 1974.
- **Docking Attempt**: Failed to dock with Salyut 3 (specifics of the failure are not detailed in the source material).
- **Landing**: August 28, 1974, in Kazakhstan.

### Significance and Aftermath
Despite its failure, Soyuz 15 contributed to the Soviet space program’s understanding of docking mechanics and space station operations. The mission was followed by **Soyuz 16**, which continued testing for the Apollo-Soyuz Test Project. The Soyuz 7K-T spacecraft used in this mission became a standard for subsequent flights, proving its adaptability for both short and long-duration missions.

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## References

1. Jonathan's Space Report
2. Freebase Data Dumps. 2013
3. [Source](http://www.spacefacts.de/mission/english/soyuz-15.htm)