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The Martian - Ares I Mission Replica by APlayer


APlayer

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Hello people! This community is awesome, and I want to be awesome too. So here's my clumsy attempt at this:

A while back, after I've read The Martian, I was totally hyped and made an Ares style mission to Duna. Of course it had some mishaps and stuff. This was in 1.1.3. Now, that all the mods I've been waiting for have updated to 1.2 and holidays have started, I figured I could try it again and do better, and share it here.

So, this is the thread I'll be posting my progress in, I plan to do this topic like the Kron missions one, and will post succeeding missions here too, and it will be pic heavy.

Just like last time, I will do this in a Sandbox save. I may some day try to pull it off in career... but not now. I will use a HEAVILY modded install, including mods that make your life harder, like Kerbalism. Also, the way I do missions, the planning phase of it takes a few times the execution phase, so expect the first week or so to be just craft building and assembling, trajectory planning and such.

My main mods will be Nertea's NearFuture Technologies and Kerbalism, but there will be bits from many other mods too. I also use tools such as KER and the Transfer Window Planner, but no autopilots like MechJeb.

 

Here is my mission objective list (Skip if you don't like reading, this is more of a checklist for myself):

 

  • The interplanetary vehicle must be reusable

 

  • It must include the following components:
    • A science lab
    • A torus
    • A cupola
    • Living space for a crew of six
    • Ion engines, because it will be too heavy else
    • Probe control
    • Adequate HGAs
    • LGAs
    • Docking ports in normal and JR. size
    • Lighting on critical or fragile components and docking ports
    • Adequate KIS storage space
    • KIS Beer for everyone, one for Kerbin departure, Duna landing, Duna departure, Kerbin arrival

 

  • It must include the following crew comforts:
    • Maximal radiation shielding
    • At least two seats per Kerbal
    • Adequate living room according to Kerbalism

 

  • It must include the following safety measures:
    • In case of a complete elecricity generation failure, it must be able to run for 6 hours at full capacity (not including engines) and after that six hours in emergency mode, powering only the life support
    • 150% of the trajectories fuel requirements
    • One additional Kerbal-year worth of life support supplies
    • At least double redundancies for non-critical but fail-able component
    • At least triple redundancies and high quality manufacturing of mission critical and fail-able components, including: Engines, antennae, electrical supply
    • Quadruple redundancy and high quality manufacturing of engines

 

  • The surface operations must be performed under the following conditions:
    • The supply probes must be landed within a radius of 1000m around the target
    • The crew must have a hab module on the surface
    • The crew must have two 3-seat rovers with KIS racks and some storage for any used resources on the surface
    • The crew must have enough supplies to last for 45 days on the surface
    • Every surface component holding life suppport resources or fuel at any moment in the mission must have KIS valves
    • There should be as much science payload as possible

 

  • The ascent vehicle must have the following capabilities:
    • Have medium radiation shielding
    • Have quad engine clusters on any stage and be able to reach Duna orbit with any one engine per stage failing at any point
    • Be as light as possible, achievable by ISRU
    • Be able to fill its tanks by ISRU within 400 days of the about 600-700 available

 

  • The crew must spend no longer than 426 days on the mission (between the interplanetary ejection burn start and Kerbin orbit injection burn end)
  • 30 days must be spent on the surface of Duna
  • The mission should cost no more then 3 Million funds the first time and 2 Million funds the second and following times, not including failure replacements and other maintenance costs

 

  • Backup and emergency plans should be available for:
    • Ascent vehicle failure at any stage before the crew descent
    • Any probe loss before the crew descent
    • Any rendezvous and docking failure mid-mission
    • Crew landing off-target by up to 100 km
    • Surface emergencies
    • Piloting failure during ascent resulting in unsafe altitudes
    • Piloting failures in space resulting in missed target trajectories

 

  • Just for this mission, there are three types of launchers planned:
    • 1) Heavy cargo, 3.75m fairing diameter, 30 tons to Duna flyby or Kerbin high orbit capability, up to 100k funds cost per launch
      • Projected three launches to assemble the ship
      • Projected five launches to Duna with surface components (Hab, Descent Vehicle, Ascent Vehicle, Rovers, Science/Hab/Rover components)
      • -> Estimated payload costs: 1000k ship + 20k Hab + 20k Descent Vehicle + 60k Ascent Vehicle + 20k Rovers + 50k Components = 230k
      • -> Total launch costs: 2030k including ship, 1030k without ship
    • 2) Light cargo, 1.4m fairing diameter, 5 tons to Duna flyby or Kerbin high orbit capability, up to 20k funds cost per launch
      • Projected three launches for ship supply
      • Projected three launches for orbital survey & relay sats, landing site investigation rover
      • Projected two launches for surface supplies
      • Estimated payload costs: 50k - 200k (Argon/Xenon) supplies + 20k survey/relay/rover + 30k surface supplies = 
      • -> Total launch costs: 290k - 440k
    • 3) Crew, 2.5m fairing diameter, 3 crew + 5 days of supplies to Kerbin high orbit capability, up to 50k funds cost per launch
      • Projected two launches to bring crew to the ship
      • Estimated payload costs: 30k per crew capsule
      • -> Total launch costs: 160k

 

  • -> Total estimated mission costs 2.5 to 2.6 Million first time, 1.5 to 1.6 Million second and following times

 

Sorry for the long list. As I said, it is more like a personal checklist. Also, a lot of it is heavily based on what I experienced when I did this back in 1.1.3, that's why I think it is pretty accurate.

Plan for today: Start building the ship. This is first, because I need an estimation of the TWR for planning the trajectory. I expect it to be significantly less than 0.05 (Last was about 0.005 - yay, ion engines for the win!) and I don't want to split my burn, this is too complicated to plan. So I need to know what orbital altitude is adequate to start with a given ship, before planning the trajectory (The burn should last no longer than 1/3 of the orbital period).

 

If you wonder how long it took to finish the burns (Max deltaV was 2.863km/s, I had noted it) - it took 8h 50min in game time. I downloaded a mod to allow for x8 almost-lag-free physical timewarp and went to have dinner while the burn was executed. I had plenty of time left when I came back.

 

If you read until here, then thanks for your attention, you're really patient, sir! :D

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I'm looking forward to it too.  I have an Ares inspired and a Constellation/1960s Russian inspired mission leaving for Duna soon in my sandbox save.  Its not suppose to be an Ares replica or even close match so I'll be very excited to see what you do in yours.  I use USI-LS but I've been curious about Kerbalism so I'll certainly follow your mission to see how it works.

 

Best of luck!

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Thanks, guys! I almost finished the ship, currently I am looking for some smaller life support details. But the most important part, meaning the TWR, should be settled now: 0.007. That means I can start calculating my trajectories. (Pics as soon as I finish it.)

To anyone who doesn't know it yet: Try this tool! It's absolutely amazing!

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Update:

 

Pictures time!

 

EjdNqQj.jpg

qH880S4.jpg

 

Generally showing off craft in action, no technical details: http://imgur.com/a/fIWzZ

VAB images with technical information and split view: http://imgur.com/a/W8uoy

(Edit: I made small modifications like lights pointed at the torus which are in the second album but not in the first)

 

Craft specs:

When assembled, fueled and supplied:

  • + 36 spare parts in KIS storage
  • Mass: 83,183 kg
  • Cost: 788,204 funds

When assembled, but dry and empty:

  • Mass: 53,427 kg
  • Cost: 452,556

General:

  • Part count: 156
  • DeltaV: 18,034 m/s
  • Crew capacity: 6
  • TWR: 0.007 - 0.014
  • Propulsion system: 4x redundant Ion thrusters, 3.6 kN each, all at 1/4 power to stay withtin EC margins
  • Fuel: 7,560 kg of Xenon
  • Main power generation: 1x 400 EC/s nuclear generator
  • Auxilary power generation: 4x redundant ~10 (Duna) - ~24 (Kerbin) EC/s solar arrays
  • Power storage: 41,390 EC directly stored throughout the vessel, 96,000 in NFT capacitors - in case of a complete loss of power enough for 3 h normal operations and then 8:42:43 h of emergency mode, or run the ship full with engines for 5:36 min
  • Power Emergency Mode (PEM): Saves 85% of power - 1.34 EC/s vs. 8.83 EC/s normal
  • Main ACS: 1.97 kNm from 4 sets of 4 thrusters, enough MP for 30 minutes of continuous burning
  • Auxiliary ACS: 0.8 kNm from 2x 2.5 m inline reaction wheels + 1x reaction wheels in pod
  • Adequate cooling at the reactor and engines
  • 7.24 Kerbal-Years worth of Food
  • 8.46 Kerbal-Years worth of Water, using recyclers
  • 12.51 Kerbal-Years worth of Oxygen, using chemical plant as recycler
  • 2.08 Ship-Years worth of Nitrogen, extends to 5.42 Ship-Years in power emergency mode (Less hab volume)
  • Lighting on every critical, dangerous or fragile element
  • All component objectives fulfilled but one: KIS beer. I was disappointed to find they must have deprecated it. :(

-> Seriously missing only backup power supply scenario: 3 hours instead of 6. Justification: Batteries already mass ~3 tons. Adding 3 t more would be too much for this unlikely scenario (All solar panels failed? Unlikely. Reactor core life time exceeded due to failed solar panels? Possible. Provided spare solar panels for this, every TWO can power the ship in emergency mode, I bring six. 9 critical solar panel failures + reactor failure? Nearly impossible!)

 

Ship consists of 5 modules, front to back:

Crew Module (CM):

  • Heaviest in the dry ship due to shielding: ~27 tons
  • Holds the crew and the torus
  • Front docking port
  • Manned command module

Service Module (SM):

  • Holds capacitors, two solar arrays
  • RCS fuel, life support supplies, KIS storage
  • The chemical plant
  • Low gain antennae
  • Airlock/Docking modules attached to it

2x Airlock/Docking Module (DAM):

  • Attach to Storage compartment
  • Hold high gain antennae
  • An airlock, JR. size and normal size docking port on each
  • Used for EVAs and resupply docking

Propulsion Module (PM):

  • Holds the Xenon and engines
  • Batteries, reactor, two solar arrays
  • Radiators

 

Plan for tomorrow: Search for a trajectory. I will use my notes from the old ship as a reference, the trajectory can be very similar.

Edited by APlayer
Error correction
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This time, I decided to take a shot at calculating the needed angle at which to start the burn and do a continuous burn. It would greatly increase efficiency of the ship assembly phase and the transfers.

For this I plan to write a script in whatever (JavaScript, Python or on my calculator... why not?) which approximates the long burn with a series of shorter ones. I dug through the internet in the search for formulas and basically found everything I need or everything I though of, at least, except one: When you preform a prograde or retrograde burn not at your periapsis or apoapsis, but at a know radius from the periapsis: How can you describe the change of periapsis and apoapsis? Could anyone help me here?

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Update:

I just derived the needed equations from the vis-viva-equation and the SMA equation. Now I've got a ton of scribble on Post-It notes, two needed equations and a headache. :P

Here are my equations, I guess this is the final list and all else can be derived from those easily:

e = (rmax - rmin) / (rmax + rmin)

p = (rmax * rmin) / a

r = p / (1 + e * cos(theta))

v = sqrt(G * m (2 / r - 1 / a)

rmin = a - (G * m) / v^2 + r / 2

rmax = a + (G * m) / v^2 - r / 2

a = (rmax + rmin) / 2

 

...where...:

...e is the orbital eccentricity

...rmax is the distance to the center of the planet at apoapsis

...rmin is the distance to the center of the planet at periapsis

...p is just some weird parameter used in formulas, still no idea what it's for

...a is the semi-major axis

...r is the current distance to the center of the planet

...theta is the true anomaly

...v is the velocity

...G is a constant and equals to about 6.674×10−11

...m is the mass of the planet

 

 

Also, while posting, I noticed I still miss a way to describe the travelled distance along the orbit. So here goes more maths.

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maltesh from the IRC channel suggested an approximation - it is somewhat hard to explain, boils down to approximating the movement as a straight line and then determining the angle that has passed per trigonometry. So that means I am good to go, and will try to write a script today. Also, I will probably use JavaScript, because then more people than just me could use it. Plus I am more skilled in it than in Python.

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I figured I am wasting time with that script. I don't think it makes sense to waste so much of it for this challenge. Lesson learned.

Anyway, then the backup plan is used: Start from a high orbit, so that the burn takes no longer than 1/3 of the orbit.

 

In other news, I found a suitable launch window, which allows me to plan a mission timeline:

  1. Y1/D127 - Y1/D177: Launch and assembly of scouting and relay probes
  2. Y1/D177: Departure of scouting and relay probes - they arrive ahead of the rest, trajectory Δv: 1.9km/s
  3. --- 14 days break ---
  4. Y1/D189 - Y1/D239: Launch and assembly of other components except Hermes
  5. Y1/D238: First Kerbin - Duna launch window occurs, departure of other components, trajectory Δv: 1km/s (aerocapture)
  6. --- 207 days break ---
  7. Y2/D19: Scouting and relay probes arrival
  8. Y2/D19 - Y2/D69: Scouting probes and landers deployment, building relay net
  9. Y2/D69: Arrival of other components, aerocapture, precise landing, deployment
  10. --- 333 (lucky!) days break ---
  11. Y2/D403 - Y3/D26: Launch and assembly of Hermes
  12. Y3/D26 - Y3/D31: Launch of crew, docking with Hermes, last minute preparations and checkout
  13. Y3/D31: Crew departure with Hermes, trajectory Δv: 4.6km/s
  14. --- 288 days break ---
  15. Y3/D319: Hermes arrival
  16. Y3/D319 - Y3/D324: Docking with descent vehicle, last minute preparations and checkout
  17. Y3/D324: Crew descent & landing with descent vehicle
  18. Y3/D324 - Y3/D354: Component assembly, surface operations, ascent preparations
  19. Y3/D354: Crew ascent with ascent vehicle
  20. Y3/D354 - Y3/D359: Docking with Hermes, last minute preparations and checkout
  21. Y3/D359: Hermes departure, trajectory Δv: 4.6km/s
  22. --- 98 days break
  23. Y4/D31: Crew arrival with Hermes
  24. Y4/D31 - Y4/D36: Re-docking with crew capsules, last minute preparations, crew descent
  25. Y4/D36: Crew recovery

 

Trajectory details:

Scout probes:

  • Departure: Y1/D177
  • Arrival: Y2/D19
  • Time of flight: 268 days
  • Parking orbit: 100 km
  • Ejection Δv: 1,145 m/s
  • Insertion Δv: 776 m/s
  • Total Δv: 1,921 m/s

Other components:

  • Departure: Y1/D239
  • Arrival: Y2/D69
  • Time of flight: 255 days
  • Parking orbit: 100 km
  • Ejection Δv: 1,046 m/s
  • Insertion: Aerocapture
  • Total Δv: 1,046 m/s

Hermes (Kerbin - Duna):

  • Departure: Y3/D31
  • Arrival: Y3/D319
  • Time of flight: 288 days
  • Parking orbit: 7000 km
  • Ejection Δv: 2,975 m/s
  • Insertion Δv: 1,629 m/s
  • Total Δv: 4,604 m/s

Hermes (Duna - Kerbin):

  • Departure: Y3/D359
  • Arrival: Y3/D319
  • Time of flight: 98 days
  • Parking orbit: 3000 km
  • Ejection Δv: 2,756 m/s
  • Insertion Δv: 1,887 m/s
  • Total Δv: 4,643 m/s

 

With that settled, I can begin planning and building the probes and vehicles.

Edited by APlayer
Removed unnecessary leftovers copied from the launch window planner
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From tomorrow and for a week, I'll be on vacations and not online, or at least not playing KSP. So this is probably my last update before I disappear for a week.

 

Seeing that the Hermes parking orbit at Duna is 3000 km, and with this sufficiently far from Ike (~2880 km) to be noticeably asynchronous, meaning having a significant relative motion, and close enough to be influenced when passing above Ike, I figured this can't do.

I have three viable options now:

  1. Look for a synchronous parking orbit, as far away from Ike as possible, so that the mission time is not enough to result in a close approach
  2. Raise parking orbit to 4500 km, resulting in a Hermes trajectory dV increase of 79 m/s and lander trajectories dV increase of 9 m/s
  3. Select a parking orbit around Ike

I think I'll go with 2., considering the fact that this is just a cheap and safe approach with no potential difficulties. (Ike might get in the way while landing or ascending, but hey. Why did I leave myself 5 spare days? For looking at them, or what??

 

Also, I've built and tested the ascent vehicle. Pics coming in a few minutes, need to make them first.

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DAV pictures in the VAB, with breakdown: http://imgur.com/a/FmvvC

No in flight pictures this time, sorry... I had to do some modifications to the vehicle during testing, to make remote control possible without relay sats, so the vehicle itself was more ugly than usual. Plus there was some glitch weirdness (A Duna year took less than two Duna days? Huh?? I blame mods. Need to test that once I return.) and Ike eclipses all the way through it, so it was dark often. The pictures wouldn't be any good, for short.

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I returned from my holidays somewhat refreshed and ready to start playing KSP working!

 

On 12/31/2016 at 2:47 PM, Firemetal said:

Ah... Ion engines are rarely used for pushing a big mothership like that around the solar system. I'm curious. How long do the burns take? But it looks great so far!

Thanks! The last time I did this, a burn took 8:50 hours. But back then, the burn was at 0.005 TWR and 2,863 m/s of dV. This time I have a TWR of 0.0075 and 2,975 m/s of dV - this extrapolates to roughly 6 hours.

But these are the longest burns - the other ones will be shorter.

 

On 12/31/2016 at 9:16 PM, Mad Rocket Scientist said:

This is amazing!  I can't wait to see what it comes out like.

Thanks! Let me be honest - I can't wait too! :D

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Duna Descent Vehicle (DDV) done!

Pics: http://imgur.com/a/nxkyk

 

I had some difficulties with the design, as I need about 400 m/s of dV after aerobraking just to raise my orbit to the altitude where the Hermes would dock with the DDV, and then to descend to the atmosphere again. RCS would not do. But I came up with a solution: No aerobraking. I am keeping the transfer stage and using it for those maneuvers. I will "only" need about 1 km/s of dV in it for a direct insertion and the descent. 

I will probably need a special transfer stage for this, I planned to use LOX for them, but it would boil off in this case. Also, the vehicle is about 10 - 15 tons below the maximum payload mass allowance, so I should be fine.

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Today I've had an idea for a nice touch: Why not make the booster rockets modular? E.g. two or three lower stages common for all the rockets, recoverable if possible. Optional boosters, probably parachute landed. And various upper stages, depending on the purpose, which would do nicely in combination with the payloads.

This would allow me to have a standard booster while still being suited for most things the mission would throw at me. Also, it would mean a more or less similar launch timeline which would facilitate piloting. This is especially important since I hope to have them recoverable.

 

Also, I started on the hab now. I have trouble designing a launch and landing system for it, it is from KBPS and thus non-standard form factor. And there will be one surprise which I found especially neat. :-)

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Hab and Presupply 1 finished. The presupply probe carries mainly the solar farm for the hab (it's working! Mini solar panels to carry around and equipment to build an EC net with them!), which is the surprise I promised. Some may find it trivial, but I am proud of it. :)

 

Pictures:

Hab: http://imgur.com/a/29pyW

Presupply 1: http://imgur.com/a/5f0NG

Not all landing pics included, Ike eclipses again. Also, I didn't assemble it, that would require landing an actual crew and both probes in one place. KRASH (My simulator program, like HyperEdit but with force-revert and costs funds in Career mode) does allow only one vessel landed at at time.

But I am fairly confident it will work. I provided plenty of redundancy and I did this once before. Not quite like that, but similar.

Edited by APlayer
Posted too early by accident
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Quick check against the checklist:

 

(I have given each component an estimated percentage of the total efforts which it will take/took)

What's done?

  • (20%) Hermes
  • (10%) Duna Ascent Vehicle (DAV)
  • (5%) Duna Descent Vehicle (DDV)
  • (5%) Hab (SOB, SP1)

What's left to do (Probably in the order I will do it)?

  • (2.5%) Life support surface presupply/ies
  • (2.5%) Science instrument surface presupply/ies
  • (10%) Rovers
  • (5%) Survey sat/s, lander/s
  • (5%) Relay sats
  • (10%) Crew capsule
  • (5%) Hermes resupply craft
  • (20%) Launch system

 

Summary:

Mission preparations are done by about half! (45%)

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  • 2 weeks later...

Sorry for the long break, I've had a lot of stuff to do in real life recently and didn't come to play KSP. But now I built four more presupplies, two are identical, the rovers, one is for the science and one is for the life support equipment. Also, I made the relay and survey sats.

Pics:

Presupply 2/Life Support (SP2), Presupply 3/Science (SP3), Presupplies 4 - 5/Rovers (SP4, SP5): http://imgur.com/a/KGbeF

Interplanetary Communications System "IComS" (IC1 - IC6), Planetary Surface Mapping System "PlaSMa" (SM1 - SM6): http://imgur.com/a/bGUn9

 

Next come the crew capsule, resupply and launch crafts.

 

TL;DR for the following paragraph: The mission is in the budget margins - First mission costs 2,551,849.26 - 2,751,849.26 Funds, second and following cost 1,770,652.96 - 1,970,652.96 Funds.

I am so far in my budget - all single use crafts and the Hermes' supplies cost 1,130,652.96 Funds, I include 150,000 Funds estimated costs for the crew capsules and resupply crafts. Seven of those crafts are of the "Presupply Form Factor", e.g. will be launched with the light kind of launcher. Five to seven (I am not sure how many resupply crafts there will be, I estimate one to three) will be launched by the heavy kind of launcher. That totals to 640,000 - 840,000 for the launch costs, thus we have a total cost of 1,770,652.96 - 1,970,652.96 Funds for a second or following mission. I planned for 2,000,000 Funds. The Hermes costs 461,196.30 Funds when empty, requires three heavy launches and one light launch. That equals to 320,000 Launch costs and 781,196.30 Funds total costs. The first mission costs 2,551,849.26 - 2,751,849.26 Funds. I planned 3,000,000 Funds. That is if we launch the satellite networks new for every mission. 

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  • 2 weeks later...

So, I am currently working on the crew launcher. I decided that the rockets will look like the SLS which, with some squinting and imagination required, actually worked out (kinda).

The SLS Block 1B Crew is passing the final checkout, it flies like a charm so far. Equipped with an abort mechanism and lots of automation (SmartParts), you have next to no headaches flying it.

Cost: 69,693 funds per launch, with the lower stage and boosters recoverable. Plus the landing part of the capsule, obviously.

Total cost per launch, with recovered value subtracted: About 40k. Cannot say exact number, as the recovery percentage varies. This is half of the allocated budget, as recoverable stages were not initially considered.

 

Automated processes:

  • Launch sequence properly timed
  • Automatic SRB staging
  • Complex staging processes only need one key press
  • Landing sequence
  • Abort sequence

Safety measures:

  • Safe launch abort possible at any time, crew safely lands in the ocean
  • Big fuel margins -> Early cutoff, one engine out scenarios both reach orbit
  • Parachute redundancy
  • Correction thrusters available at all times, even after an abort
  • EC margins: 1.5 h (battery) + 15 h (backup generators)

Other features: 

  • Powered capsule touchdown, Soyuz style
  • Full unmanned guidance, can stand by until the Hermes returns from Duna and land the crew
  • Redundancies for communications, RCS, Reaction Wheels
  • Maximum abort G-Load: 6.35 G (during launch escape) aborts in a short phase have 7.31 G during parachute deployment
  • Maximum nominal G-Load: 3.51 G in rare cases during parachute deployment

Pictures following soon.

Edited by APlayer
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