The European Space Agency has long harbored hopes that it could launch humans aboard Russian Soyuz spacecraft from its French Guiana spaceport, but this is likely impossible, Space.com has learned.
The agency has claimed in the past that such future manned Soyuz TMA flights need only infrastructure changes at the launch site to be realized, yet ESA has known since 2004 that the spacecraft can't be launched from the South American territory.
An ESA study conducted between 2002 and 2004 found that because the Soyuz has not been designed to land in the sea, a French Guiana launch that had to be aborted would endanger the spacecraft and its crew as it would likely have to ditch in the Atlantic Ocean.
The Soyuz spacecraft have always landed on land in the former Soviet territory of Kazakhstan.
Aiming for manned launches
Manned Soyuz launches from the French territory have been a declared aspiration for ESA ever since work began on the "Soyuz at the Guiana Space Centre" program. This program culminated in the first unmanned launch of a Soyuz rocket from French Guiana Oct. 21, 2011.
The advantage of launching Soyuz rockets from this equatorial location is that their payload capacity to reach geostationary transfer orbits (not the International Space Station) is almost double compared with taking off from Baikonur in Kazakhstan or Plesetsk in Russia — the other two Soyuz rocket-launch sites. Launches from near the equator get this payload boost from the Earth's rotation.
Despite knowing about the sea-landing problem, ESA's Soyuz information page states: "the (French Guiana) launch infrastructure has been designed so that it can be smoothly adapted for human spaceflight, should this be decided." No mention has been made of the fact that the Soyuz TMA would have to be extensively modified to land in the sea.
Space.com has obtained a technical paper about the 2004 study, which was conducted by ESA's launcher directorate and its "Soyuz at the Guiana Space Centre" program.
According to the paper, "the (Soyuz) re-entry capsule has not been designed to travelling on water and its evacuation following splash-down in the ocean in the event of an aborted launch may result in a particularly difficult experience for the crew." Such difficulty puts the lives of the crew at greater risk.
ESA has not made the full study report available in time for publication. Since 2004, ESA has done no further work to tackle this issue.
In response to the report's findings, ESA officials told Space.com, "theoretically all is possible but manned flights from (French Guiana) would be a major endeavor, requiring huge investments."
The agency officials also raised doubts about the feasibility of modifying the Soyuz for a sea landing. "In (the) case of sea landing (we would need) to verify whether the current capsule can be adapted," officials said.
In 2010, Russia launched the first of a new series of Soyuz TMA vehicles that have digital flight controls. The first flight of this version, denoted with the suffix "M," had problems.
During its Oct. 7, 2010 flight, the Soyuz TMA-01M's digital system suffered a computer-display malfunction, depriving cosmonauts of flight data. That spacecraft did land safely in March 2011, and the second digital Soyuz TMA-02M launched successfully later in June, but the problems of -01M show how difficult spacecraft adaptation is.
Meanwhile the Soyuz rocket itself has seen changes for ESA's needs.
The rocket, generically called Soyuz-ST, has two versions, the Soyuz 2-1a and Soyuz 2-1b. Both have an additional electronic flight-safety system that ESA required and larger fairings, while the 1a and 1b denote differences in their third stages.
While the French Guiana Soyuz launch site is largely a replica of those at Baikonur and Plesetsk, it has a mobile gantry tower that protects the rocket from rain.
In a change from Russian launch operations, ESA adds the payload stage to the rocket stack while it is vertical and in the tower. In Russia, payload stages are added while the rocket is still in a horizontal position, as a part of the overall assembly process.
In addition to the difficulty in modifying the Soyuz for sea landings, many infrastructure changes would be necessary for a manned launch from South America.
The 2004 study details the need for astronaut-specific access platforms in the mobile gantry, an additional lift and astronaut escape-chute system, a new vacuum chamber for capsule-tightness checks, an electromagnetic-compatibility chamber, an additional S-band mobile station, electrical, fluid and mechanical ground-support equipment, deforestation of a circular area up to 3.1 miles (5 kilometers) around the launch pad for launch aborts that will result in a land landing, and a new container for Soyuz TMA transportation from Russia to French Guiana. All these issues are technically simpler than re-engineering a spacecraft for a sea landing.
For many years ESA has looked at manned operations from French Guiana using its Ariane 5 rocket, which is built by EADS Astrium.
It was originally conceived to launch the canceled Hermes mini-space shuttle. In the last few years, ESA has studied a crewed evolution of its Automated Transfer Vehicle, which supplies cargo to the space station.
The French space agency CNES also funded a study into launching NASA's Orion capsule using Ariane 5.
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