Endeavour, Houston, we see a nominal MECO, welcome to space.
Soyuz is an absolute workhorse of human spaceflight and was developed in the Soviet Union during
spaceflight's earliest days.
When I say Soyuz, I'm referring to two things.
The Soyuz rocket and the Soyuz spacecraft.
The Soyuz rocket is used to launch Soyuz spacecraft as well as other satellite payloads.
Currently, Soyuz rockets launch from Baikonur Cosmodrome in Kazakhstan, Plesetsk Cosmodrome
in Russian, Vostochny Cosmodrome in Russia, and Guiana Space Centre in French Guiana.
Soyuz rockets are assembled horizontally in a hangar near the launch pad.
They arrive at this hangar in pieces called, Block A, Block B, C, D, E and F. And they're
assembled like this...
First, with the upper and lower halves of Block A being put together.
Then, Blocks B, C, D and E are attached around the outside.
Then, Block F with the payload ontop is attached last.
Let's have a look at the engines on the central Block.
At first glance, it looks like it has 4 large engines and 4 small engines, but plot twist!
All of these nozzles and combustion chambers are fed by the same fuel pump (or turbopump),
so this who setup is actually one engine.
The 4 largest nozzles in the middle are fixed in place, so to provide steering, their engine
has these 4 smaller vernier thrusters.
Each can swivel like this to provide steering.
The side Block engines are virtually the same, but each has 2 vernier thrusters instead of
4.
Once assembled and ready to launch, the Soyuz rocket is rolled out to the launch pad on
railway lines.
It's then lifted vertical at the launch pad, fueled, and launched.
Soyuz launches consist of 3 stages.
The first stage consists of firing the central Block A and the 4 Blocks B, C, D and E attached
around the outside.
Then, the 4 side blocks separate, starting the 2nd stage, which is just continuing to
fire the central Block A. Finally, the third stage is Block F firing.
Rather interestingly, the 3rd stage starts firing just shortly before separation.
This is done to make sure the fuel is being pushed into the back of the fuel tank so it
can be pumped into the engine.
When a Soyuz spacecraft launches on top of a Soyuz rocket it is shrouded in an aerodynamic
fairing.
On top of this aerodynamic fairing is a launch escape tower, this is a rocket motor that
can pull the spacecraft to safety if anything goes wrong with the rocket beneath it.
Just before first stage separation, this launch escape tower is jettisoned, from now on if
the crew needs to escape during the launch, there are motors around the outside of the
fairing that will fire, pulling them to safety.
If a launch escape is triggered then grid fins around the outside of the fairing will
deploy, to keep the spacecraft stable while it is escaping.
If everything goes according to plan, 2 and a half minutes into the launch, the fairing
will jettison.
Eventually, when it reaches orbit the Soyuz spacecraft will separate from the rocket and
then deploy its solar panels.
The Soyuz spacecraft has 3 modules, the orbital module, the descent module and the instrument
& propulsion module.
The descent module has seats for 3 cosmonauts, and those cosmonauts have access to the habitable
space in the descent module and the orbital module.
The instrument and propulsion module, however, has no habitable space as it is entirely taken
up by well... instrument and propulsion equipment.
And that includes the main orbital manoeuvring engine called SKD or in Russian "Сближающе-корректирующий
двигатель" SKD has this cover over it that gets uncovered whenever it needs to
fire for an orbital manoeuvre.
These days, Soyuz flights take cosmonauts, astronauts and supplies to the International
Space Station.
To dock with the station, Soyuz has an automatic docking system called Kurs.
If something goes wrong with this system, the crew inside the Soyuz can take over and
perform a manual docking.
The front of the orbital module contains the docking mechanism.
The mechanism that Soyuz uses is called SSVP which is an acronym for "Система стыковки
и внутреннего перехода" which is Russian for "System for docking and
internal transfer" It works using a probe on the Soyuz spacecraft and a drogue on the
docking port at the International Space Station.
The drogue is a cone-like structure so that when the probe bumps into it, it gets pushed
into the middle where it can latch in.
This is a soft capture.
The probe then retracts, pulling the Soyuz into the docking port, then hard capture latches
in the docking rings can latch together.
The probe and the drogue both open up as hatchways between the ISS and the Soyuz.
Once Soyuz is ready to end its mission and it's undocked from the ISS, it will perform
a deorbit burn using the SKD engine in the instrument & propulsion module.
This deorbit burn occurs about half an orbit away from the intended landing site in Kazakhstan.
After a successful deorbit burn Soyuz will separate into its 3 distinct modules.
The descent module, where the cosmonauts sit snugly inside, is the only module that will
make it down to Earth's surface.
The other 2 modules are doooomed to their fate of burning up in the atmosphere.
During reentry, the Soyuz descent module will fly heatshield first but at a slight upwards
angle.
This helps to provide a small amount of lift, keeping the module in the thinner upper atmosphere
for longer, putting fewer G forces on the crew compared to a quicker ballistic descent
straight into the thiccer atmosphere.
Once the descent module has cleared the fiery rigours of reentry and it's dropping straight
down, it'll deploy its one massive parachute.
It also has smaller backup parachutes in case this main one fails.
At an altitude of 5.8km the descent module will let go of the heatshield, exposing 6
solid rocket motors underneath the module that will aid in cushioning the landing.
Initially, the descent module will be hanging at an angle under the parachute to assist
the airflow in dissipating heat, but as it gets closer to the ground it'll shift into
an upright orientation for a safe landing.
At an altitude of 5 and a half km the systems onboard will begin to equalise pressure inside
the module with the surrounding atmosphere.
At an altitude of just 0.7m from the ground, the solid rocket motors on the base of the
capsule will fire, softening the impact and we have touchdown.
The mission has come to an end.
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Until next time, I'll catch ya later.