New ISS crew set to lift off on Soyuz-FG from Baikonur on first crewed launch of 2017
Final preparations are underway for the launch of Expedition 51/52 crew members, NASA astronaut Jack Fischer and Russian cosmonaut Fyodor Yurchikhin, to the International Space Station (ISS). Roscosmos‘ Soyuz MS-04 is currently set to lift off from the Baikonur Cosmodrome in Kazakhstan at 3:13 a.m. EDT (07:13 GMT) on April 20, 2017, and will be the first crewed Soyuz launch of 2017.
A little late, a little light
Soyuz MS-04 was originally to have launched in late March 2017, though it was bumped to April 20 when a leak was discovered in the thermal control system of the prime spacecraft, forcing the swapping of Vehicle № 734 with Vehicle № 735.
The new spacecraft completed its series of readiness checks on April 12, 2017, and the encapsulated assembly is now undergoing final prelaunch processing for its flight to the ISS.
Though the Soyuz is capable of ferrying three passengers to the ISS, Soyuz MS-04 will only have two of its three seats occupied. Roscosmos plans to temporarily reduce the number of crew in the Russian segment of the orbiting outpost until the Multirole Laboratory Module (MLM) is launched later in 2017 or in early 2018.
The crew reduction will allow Russia to cut a Progress launch from its manifest and to focus resources on getting MLM completed. It has been reported that Russia plans to return to a full complement of cosmonauts once MLM becomes operational.
Same body, new brains
Soyuz MS-04 marks the fourth flight of the upgraded Soyuz crew capsule. Largely modeled on the TMA-M variant of the venerable Soyuz spacecraft, the MS sports significant upgrades “under the hood”.
Indeed, RSC Energia has classified the avionics upgrade as being a radical improvement over its predecessor.
Outfitted with a more modern suite of digital communications and radar systems, the MS series will be able to maintain communications, via the Luch-5 relay satellites, with Russian mission control through nearly 70 percent of an orbit.
The Kurs-NA docking system has received a substantial upgrade, as has the Klyost onboard video system. Klyost, now using a digital video system, can communicate directly with the ISS via the space-to-space communications system.
RSC Energia, the firm contracted to build Russia’s next generation of crewed spacecraft called “Federation”, believes the MS variants of Soyuz and Progress will serve as a testbed for the new technologies meant for that new crew capsule.
Workhorse rocket for the ride uphill
The Soyuz MS-04 spacecraft will sit atop the 162.4-foot (49.5-meter) tall Soyuz-FG rocket. A modernized variant of the then-Soviet R7 rocket that launched Sputnik and Yuri Gagarin, the FG features a digital guidance system that enables greater reliability and flexibility.
The Soyuz-FG is two-stage launch vehicle, supplemented with four strap-on tapered boosters that give the Russian rocket its unique appearance.
At ignition, the core stage’s RD-108A engine is ignited simultaneously with the four RD-107A engines in the boosters. The quintet of engines provide 932,058 pounds-force (4,146 kilonewtons) of sea-level thrust and take several seconds to spin-up to flight pressures before the counter-weighted release arms fall away from the vehicle and allow it to rise from the pad.
Though given a different designator, the engine in the core stage is similar in design to the ones in the side boosters. All feature a single-axle turbopump, feeding four combustion chambers, and burn a mixture of a highly refined kerosene (RP-1) and liquid oxygen.
The upper, or Block I, stage contains the rocket’s avionics and is powered by a single RD-0110 engine. Like its first stage cousins, the RD-0110 burns a mixture of RP-1 and liquid oxygen, fed by a single-shaft turbopump into four combustion chambers. This vacuum-optimized engine produces 66,970 pounds-force (297.9 kilonewtons) of thrust and is part of a family of engines dating back to 1965.
The Soyuz-FG has been a reliable launch vehicle for Russia, achieving an enviable 100 percent success rate over its nearly 16 years of service.
Curt Godwin has been a fan of space exploration for as long as he can remember, keeping his eyes to the skies from an early age. Initially majoring in Nuclear Engineering, Curt later decided that computers would be a more interesting - and safer - career field. He's worked in education technology for more than 20 years, and has been published in industry and peer journals, and is a respected authority on wireless network engineering. Throughout this period of his life, he maintained his love for all things space and has written about his experiences at a variety of NASA events, both on his personal blog and as a freelance media representative.