Expedition 39 crew prepares to depart atop Russian Soyuz
The second half of the Expedition 39 crew bound for the International Space Station (ISS) is scheduled to launch tomorrow, March 25, 2014 from the Baikonur Cosmodrome located in Kazakhstan. Russian cosmonauts Alexander Skvortsov and Oleg Artemyev, together with NASA astronaut Steve R. Swanson, will travel up to the ISS aboard Soyuz TMA-12M. This will mark the 121st flight of a Soyuz spacecraft. Liftoff is currently scheduled to take place at 5:17 p.m. EDT (2117 GMT).
This will be 53-year-old Swanson’s third space flight, having already served aboard space shuttle missions STS-117 (in 2007 on shuttle Atlantis) and STS-119 (2009 on Discovery). Skvortsov will be making his second trip into orbit, following his 176-day stint with ISS Expeditions 23 and 24 in 2010, while Artemyev will be on his very first flight into the black. All three will serve initially as flight engineers, although Swanson will take over as the space station’s commander with the start of Expedition 40.
The first part of the Expedition 39 crew, consisting of commander and veteran Japanese Aerospace Exploration Agency (JAXA) astronaut Koichi Wakata, and flight engineers Richard A. Mastracchio (NASA) and Mikhail Tyurin (Russian Federal Space Agency), arrived at the station on November 6 to join three members of the previous Expedition. Transfer to the new Expedition took place on March 11.
Skvortsov, Artemyev, and Swanson have completed their preparations at the cosmonaut training center at Star City, near Moscow, and at Baikonur Cosmodrome, the world’s largest space launch facility, in the desert steppes of Kazakhstan. One of the final checks, at the Integration Facility at Baikonur, involved the crew members entering their TMA-12M craft during a fit check dress rehearsal exercise on March 14. If all goes according to plan, they will lift off from Baikonur atop a Soyuz-FG launch vehicle – a work horse of the Russian Federal Space Agency’s (Roscosmos) fleet, which has been lofting crewed Soyuz-TMA capsules to the space station since 2002.
The Soyuz rocket will depart from LS-1, also known as “Gagarin’s Start,” because this is the exact spot from which cosmonaut Yuri Gagarin began the first human journey into orbit on April 12, 1961. Since that time, hundreds more spacecraft have started their ventures from this spot, including all crewed missions to the ISS that have been handled by Roscosmos. The very first rocket to launch from here was an R-7 intercontinental ballistic missile, the forerunner of today’s Soyuz fleet; the most recent was Soyuz TMA-11M on November 7, 2013.
The Soyuz-FG is a two-stage launch vehicle with four strap-on boosters, all elements of which are fueled by a combination of RP-1 (a highly-refined form of kerosene) and liquid oxygen (LOX). The boosters, which burn for the first 118 seconds of the flight, before falling away, are each equipped with an RD-107A engine providing 188,502 lbs of thrust at near surface level. The first stage, powered by a single RD-108A engine, generates 178,161 lbs of thrust and burns for a total of about 280 seconds. Finally, after the first stage has fallen away, the second stage ignites, providing 66,993 lbs of thrust for 230 seconds from its single RD-0110 engine — sufficient to give the Soyuz capsule orbital velocity before separating.
Tomorrow’s launch to the ISS will be the 37th for the Soyuz-FG, all of which have been successful. Additionally, there have been 10 launches of its sister vehicle, the Soyuz-FG/Fregat, which uses the Fregat third stage, again with a 100 percent success record.
The Soyuz-TMA spacecraft in which the crew are housed for both the ascent to the ISS and the return to Earth, is a three-section vessel, consisting of a spheroidal Orbital or Habitation Module at the front, a Reentry or Descent Module, and a Service Module. The Reentry Module, shaped like an old car headlight, is used both for launch and the return to Earth. Its three couches and relatively spacious interior (compared, say, with the Apollo Command Module) can accommodate passengers up to 6′ 3″ in height and 209 lb in weight.
Ahead of the Reentry Module on the launch stack is the Orbital Module, which houses all the gear that is not essential for reentry, including cargo, cameras, and experiments. After launch and orbital insertion, the crew may transfer into it as a dining area or to use the toilet which is located here. It also contains the docking avionics and communications gear, and, at its far end, the docking port, through which the crew transfer to the ISS. As an enhancement over previous versions of the craft, a small window is now provided, affording the crew a forward view. A hatch between the Orbital and Reentry Modules can be closed so as to isolate the former and serve as an airlock if needed.
The third, and uninhabitable part of the Soyuz spacecraft is the Service Module which has both a pressurized and an unpressurized section. Within the former are life-support systems, the vessel’s electrical power supply, instrumentation for control and orientation, and long-radio communication and telemetry gear. In the non-pressurized portion of the Service Module is the main engine used for slowing the spacecraft after its departure from the ISS and thus beginning its journey back to the surface.
Trips to the ISS nowadays follow highly-efficient trajectories. Less than six hours after take-off, at about 11:04 pm EDT, Skvortsov, Artemyev, and Swanson will dock their Sozyuz TMA to the station’s Poisk module and begin preparations to transfer to the massively more spacious accommodation afforded by the ISS. Their capsule will remain at the station for about six months, providing an escape pod for the crew if needed.
Less than a week after their scheduled arrival at the ISS, the newcomers will be involved in receiving the SpaceX-3 Commercial Resupply Services flight. This is due to be launched, courtesy of a Falcon 9 v1.1 rocket, from Cape Canaveral Air Force Station on March 30. A month later, Progress 55 will ferry in more cargo and crew supplies, followed by an Orbital 2 supply vessel, launched from Wallops Flight Facility on May 6. At the end of May, the arrival of three new crew members, preceded by the departure of the first half of the Expedition 39 complement will see the transition to Expedition 40 and the promotion of Swanson to station commander.
Swanson, Skvortsov and Artemyev will remain aboard the orbiting laboratory until mid-September. Despite tension between the United States ad Russia over the latter’s military involvement in the Crimea region – joint missions into space are still moving forward.
Dr. David Darling is an astronomer and author of numerous books, including We Are Not Alone, Megacatastrophes, The Complete Book of Spaceflight, and his latest, The Rocket Man. His website, The Worlds of David Darling, is one of the largest and most visited science resources on the Internet. Darling is a renaissance man, he is a musician, noted author and journalist and serves as our science writer. Darling provides The Spaceflight Group with articles detailing what he knows best - space exploration.