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All the Clues

Page 3

by Sarah Jane Weldon


  07:29

  At this stage, the crew must

  07:31

  pay special attention to prepare for the next

  07:34

  critical operation: the Deorbit Burn

  07:38

  As can be seen, although the Soyuz is now

  07:40

  far away from the Station, it is still orbiting

  07:44

  the Earth at an altitude close to that of the ISS

  07:47

  The purpose of the Deorbit Burn is to force the Soyuz to decrease its speed

  07:52

  As a result, the trajectory of the vehicle changes and it re-enters the atmosphere

  07:58

  The atmosphere acts as a natural brake and does most of the work

  08:02

  in slowing the Soyuz down until a set of parachutes opens

  08:06

  and ensures a relatively soft landing

  08:10

  This braking is achieved by

  08:11

  using the main engine located in the rear side of the spacecraft

  08:15

  to push against the direction of travel

  08:18

  The required orientation and duration of the

  08:20

  braking impulse must be precisely calculated

  08:23

  and achieved because it directly influences

  08:26

  the steepness of the re-entry path

  08:29

  If we don't burn enough,

  08:31

  then we have still too much speed and we will still be too high

  08:34

  in the atmosphere and we can actually skip off the atmosphere

  08:37

  and then go further into space and that of couse would not be a successful re-entry

  08:43

  On the other hand, if we burn too much and we come in too steep

  08:46

  then we will have too much speed when we are in the lower parts of the atmosphere

  08:51

  the heat that is normally around 2000 degree Celsius

  08:54

  will be much higher and we have the risk of burning up

  08:58

  So also therefore is very critical that we do the correct deorbit burn

  09:02

  and that we really fix this around 120 m/s

  09:09

  To achieve the correct burn, the main engine fires

  09:12

  for exactly four minutes and forty five seconds

  09:22

  The Soyuz now follows a trajectory that will lead

  09:25

  it to intercept the dense layers of the atmosphere,

  09:28

  leading to a safe re-entry and landing, about 55 minutes later

  09:36

  As the vehicle travels along its trajectory, about 30 minutes before

  09:40

  landing and at an altitude of roughly 140 km,

  09:43

  it separates into three parts: the orbital module, the descent module

  09:49

  and the instrument compartment

  09:51

  There is no chance of the individual modules colliding with

  09:54

  each other, this is called impact-less separation

  09:58

  Only the descent module hosting the crew will make it back safely to Earth

  10:03

  The other two will disintegrate and burn up in the atmosphere

  10:08

  The separation of the spacecraft into three parts is happening through

  10:14

  several seconds, because there are several

  10:16

  parts that get detached one after the other

  10:19

  All this action is done with explosive bolts or with explosive implements

  10:26

  Seen from the inside of the spacecraft, it felt like

  10:29

  there was somebody outside the spacecraft with a sledgehammer that

  10:33

  was hammering here and there, up and down so every few

  10:38

  milliseconds the spacecraft was shaking with this

  10:41

  BANG! BANG! BANG! BANG!

  10:43

  It felt really interesting actually!

  10:51

  The descent module experiences extreme high temperatures

  10:55

  during re-entry, so to protect it, and the crew inside,

  10:59

  it is fitted with a special protective

  11:01

  coating and has a heat shield on its base

  11:04

  As the atmosphere becomes more dense, the descent module

  11:07

  positions itself so that its heat shield points forward

  11:11

  The capsule is about to enter the Earthís atmosphere

  11:15

  This will be the most stressful part of its journey home

  11:18

  By the time we were supposed to re-enter

  11:21

  the atmosphere, I actually looked out from our

  11:23

  window and I actually looked we were tumbling and I was a little bit puzzled

  11:29

  because I thought we needed to re-enter with a special angle,

  11:33

  so I started looking at procedures, we did a few things and when I looked out again

  11:38

  I saw that we were already inside this plasma, it was getting

  11:44

  really red and actually the window was getting pretty dark

  11:47

  what was happening was that

  11:49

  the plasma stream was actually burning the outside layer of

  11:53

  the window which has a protective cover

  11:56

  So it was kind of interesting, at that point I did not feel that much I mean

  12:01

  the gravity starts grabbing you but it is very

  12:05

  gentle at the beginning and you actually use it

  12:08

  to feel or go into the seats and buckle up,

  12:13

  pull your straps so that you really lay into the seat

  12:17

  It was an interesting feeling

  12:19

  The descent module follows a path that is similar in shape

  12:23

  to that made by a surfer riding a big wave

  12:26

  Like a surfer, the Soyuz is able to make small adjustments to keep itself on track

  12:32

  So, how is the trajectory of a free falling capsule controlled?

  12:38

  Even though it does not have wings, the Soyuz

  12:41

  capsule is able to change the way it flies through the air

  12:44

  The design of the Soyuz enables it to do this

  12:46

  The capsuleís lift increases when it rotates in one direction

  12:50

  and decreases if it rotates in the opposite direction

  12:53

  In this way, the capsule is able to keep to its planned trajectory

  12:58

  As a side effect, this rotation also induces

  13:01

  a sideways displacement of the module

  13:03

  This effect is very useful because it gives

  13:06

  more flexibility for the selection of the landing site

  13:10

  This sideways manoeuver has already been taken

  13:13

  into account when selecting the optimum trajectory

  13:20

  During the descent in the atmosphere, the crew feels the effect of

  1
3:23

  the deceleration when their weight exceeds

  13:26

  several times their own weight on the ground

  13:28

  The maximum G-load (4G) is experienced when the capsule reaches an

  13:33

  altitude of roughly 35 km while

  13:36

  it has already been travelling for 6 to 7 minutes in the atmosphere

  13:40

  Gravity is a very, very strong force

  13:43

  We do not understand here on Earth how gravity

  13:46

  has such a hold on our body and what is around us

  13:50

  You do feel it when you come back from space

  13:53

  because now you have been in a non-gravity environment

  13:58

  for a long time and then you see all these forces grabbing you

  14:03

  You look at stuff and you feel your hands are heavy,

  14:06

  you feel your watch weights a ton, your books, the materials

  14:10

  around you, your head is extremely heavy

  14:12

  It is really a very strong feeling

  14:16

  In the unlikely event that the automatic control system fails,

  14:21

  the crew is able to use a manual hand controller as a backup

  14:24

  They train extensively to prepare for this possibility

  14:29

  Another option is the ballistic descent

  14:32

  The spacecraft starts spinning and flies a much steeper trajectory

  14:36

  without any additional sideways displacement

  14:39

  The G-load in this case will increase up to 9

  14:45

  When the capsule reaches an altitude of 10.5 km, its speed

  14:49

  has already decreased from 28000 to 800 km/h

  14:54

  In order to further decrease the speed, the parachute cover

  14:58

  is jettisoned and a series of parachutes are deployed

  15:02

  At the end of the atmospheric re-entry, you really start hearing

  15:05

  the noise of the wind and the sound, you are almost breaking the sound barrier

  15:10

  Then, in the opposite direction of course you are coming back into

  15:13

  the normal area of flying

  15:23

  This is around 30000 feet that the parachute has to open

  15:27

  This is actually a very critical moment and is one of the

  15:30

  only things in the Soyuz where the crew does not have a manual override

  15:34

  So this is only an automated system

  15:36

  So far, it has always worked and we also have a backup parachute that can

  15:40

  help us in case that the main will not open

  15:42

  But it is also a very violent moment,

  15:44

  you can imagine this 2000 kilogram capsule

  15:47

  that is soaring at the speed of sound through the atmosphere

  15:51

  and then all of the sudden you have a parachute

  15:53

  that opens on the side and that pulls on you, like a little swing,

  15:58

  It is almost like a yo-yo and you see the capsule going all around

  16:01

  It is much worse than in a roller coaster because

  16:04

  the motion is in all directions and it is a little bit

  16:07

  scary for some of us, for some others it can also be fun

  16:11

  because they are like "Wow this is the best ride I've ever had!"

  16:14

  Then, a few minutes later, at a height of 8.5 km, the drogue chute

  16:19

  finally deploys the 1000 square metre canopy of the main parachute

  16:27

  This slows the capsule down to a speed of 22 km/h

  16:32

  The capsule is suspended under the parachute

  16:34

  with a specific angle relative to the ground

  16:37

  This angle helps the capsule to dissipate the heat accumulated

  16:41

  on its surface and structure during the re-entry

  16:44

  But then everything calms down, of course once that the main parachute

  16:48

  has deployed you really come to the calm air after this whole violent

  16:53

  re-entry, the violent opening of the parachute,

  16:55

  then you are hanging safely, slowly descending

  16:58

  to the Earth underneath your parachute

  17:00

  and this is actually the first time that you know:

  17:03

  Yes, I am safe, we are going to make it!

  17:08

  At an altitude of roughly 5.5 km,

  17:11

  the frontal heat shield and external window glass are jettisoned

  17:16

  The capsule vents excess fuel and oxygen from pressurised tanks,

  17:20

  to reduce any chance of an explosion when it hits the ground

  17:24

  In order to position the spacecraft adequately for the landing,

  17:27

  the main canopy switches to symmetric suspension

  17:31

  This setup ensures that the cosmonauts' seats are now

  17:33

  perfectly positioned to absorb the landing impact shock

  17:38

  The retrorockets that were hidden behind the heat shield

  17:41

  are prepared for firing

  17:43

  Inside the capsule, the crew seats automatically raise

  17:47

  in order to prepare shock absorbers

  17:50

  Usually, the Search and Rescue Team equipped with aircraft

  17:54

  and helicopters starts tracking the Soyuz capsule

  17:57

  even before the very first parachute is deployed

  18:00

  The helicopters land next to the capsule shortly after touch down

  18:04

  and the team help the crew to exit

  18:06

  Finally, 70 cm above the ground, the six retro rockets fire

  18:11

  to further reduce the capsule speed to approximately 5 km/h

  18:16

  The capsule hits the ground but the crew seats continue

  18:19

  moving down and shock absorbers help to make the landing softer for the crew

  18:26

  The soft landing is not really soft,

  18:30

  You prepare for it by putting your arms against your body, not touching

  18:34

  any of the metallic parts, hold your books against you, you are not talking

  18:39

  not to put the tongue in the middle of your teeth and you are lying there trying

  18:44

  to be as inside your seat as well as you can

  18:48

  and you are waiting for this "soft landing" to happen,

  18:52

  which for me felt like a head-on collision between a truck and a small car

  18:59

  and of course I was in the small car, so when this happened it was like

  19:03

  BA-DA-BOOM!

  19:04

  everything shook, I was kind of shaking in there,

  19:07

  everything was, and then... silence everything
was stopped

  19:12

  So I looked a little bit around, I looked at my crew members and then I said:

  19:17

  Hey guys, Welcome back to Earth!

  19:20

  Once landed, one of the first actions

  19:22

  of the crew commander is to release

  19:25

  one of the two ropes that connect the capsule to the parachute

  19:28

  This is important, as in windy conditions, it prevents

  19:32

  the capsule from being dragged away on the ground by the inflated parachute

  19:37

  You know that you are on the ground, you hear the voices of the rescue troops

  19:41

  that are next to you and you know that 5 minutes later they will open up the hatch

  19:46

  and you can breathe fresh air

  19:49

  The crew is now safely back on Earth

  19:52

  They will soon be reunited with their families and begin

  19:55

  the rehabilitation process, after their extraordinary journey

  Chapter Five

  Trouble nu set like rain

  Problems often arrive without warning

  Rynelle at airport

  Chapter Six

  When cockroach mek dance e no invite fowl

  Don't invite trouble.

  Joe arrives at airport - Brownie, sticker

  Chapter Seven

  Yu shake man han, yu nu shake him heart

  Appearances can be deceiving

  Taxi cab ride - Joe and Rynelle

  Chapter Eight

  Fowl gwine fat im begin fram him toe

  Adult behaviours begin in childhood

  Rynelle walks to university

  security guy at gate

  fuming

  just like her father

  Chapter Nine

  Mischief come by di poun and go by di ounce

  It only takes a little effort or few words to start a lot of trouble.

  Joe at first hotel with taxi driver

  receptionist

  phone call

  Chapter Ten

  Moon run faas but day ketch im

  Your actions and misdeeds will eventually have consequences.

  phone call - caught out by driver

  drive to new hotel

  Joe finds ID badge

  check in

  Chapter Eleven

  Play stone kill bud

 

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