Sigma Mission: Kerbol System Grand Tour!

[Stratzenblitz75]

Greetings!

As this is my first post of any significance, I thought I’d introduce myself:

I started playing KSP a little over a year ago and since then have poured over 700 hours into crashing rockets, testing experimental crafts(and crashing them), stranding Kerbals on other planets, and various other “normal†KSP activities. Because of KSP, I am trying to learn more about orbital mechanics and rocketry and in turn, trying to apply this knowledge in game to make my missions more efficient and precise (often with disastrous consequences). While I certainly know a lot more than I have before, I have a long way to go to becoming proficient in this area. The Sigma mission is a direct result of my basic knowledge of orbital mechanics. I hope you enjoy!

Mods used:

Hyper edit: For testing my various lander designs and for testing how much Delta V it takes to land on and return to orbit from all the planets of the solar system.

Kerbal Engineer Redux: For determining the Delta V of a craft without having to do the math myself. Also very handy for it’s in flight information.

Otherwise the mission is completely stock.

Planning the mission:

This mission began as somewhat cliché “grand tour†mission with the idea being to land on every celestial body in the KSP solar system (expect Jool and the sun of course) in one launch. The main reason I wanted to do such a mission in the first place was the fact that even in my 650 or so hours of playtime (before the mission), I had only landed on and returned from 3 celestial bodies: the Mun, Minmus and Duna and I hadn’t even seen Moho, Ike, Gilly, and Tylo. I figured this would be a great way to fill in my KSP checklist of landing on and returning from every planet in the solar system. I named the mission “Sigma Mission†after Sigma notation as I am quite literally “summing up the planetsâ€Â.

Now, before 0.23.5 this kind of “grand tour†mission (at least for me) was impossible. There were simply no stock parts that could provide the necessary Delta V to perform all the planetary transfers and landings. The only engine that could do this was the ion engine, and given its very low thrust of 0.5 Kn it would take ages to do anything and likely break your sanity in the process. In addition, it’s not capable of landing a Kerbal on many celestial bodies. However, with the buffed ion engine, this mission becomes much more feasible as now you can use an ion powered vehicle to both perform burns in a timelier manner and to land Kerbals on celestial bodies up to the size of the Mun.

With the idea planted in my mind, I designed the various landers and modules I would need for the mission. Here’s what I came up with:

Ion Lander:

Pic: https://www.dropbox.com/sc/y0k5drmq859az0n/AAAp_M__7Jlb89FTEG-aAtxja

The star of the show, the ion lander is a one man ion powered lander designed to land on airless celestial bodies up to the size of the Mun, and to function all the way out to Eeloo. It has 8 1x6 solar panels (without casings) to give it enough solar power to run the ion engine at full power in the outer solar system. To save on mass, there are no landing legs and only 1 docking port. Basically, it’s an ion powered chair.

Specs(Factoring in the mass of one Kerbal):

Propulsion: 1 PB-ION Electric Propulsion System

Fuel capacity: 700 units of xenon gas

Delta V: 4253 m/s

Mass(Full/Dry): 714/644 kg

General Purpose Lander (GPL):

Pic: https://www.dropbox.com/sc/74yn180462a0wl9/AAA5uSSKOYpUGXc9Ztg5aitaa

For what the ion lander can’t land on, the GPL is chemical rocket powered lander designed to land on both airless and atmosphere hosting celestial bodies up to the size of Tylo. Since it is designed for a Tylo landing, it is over engineered for all the other planets and can land on many of them with less than 100 units of LFO. Similarly to the ion lander, the GPL has no landing legs and only 1 docking port. However, unlike the ion lander, the GPL has a very wide landing base. This is to help with the lander’s high center of mass when its tanks are not full.

Specs(Factoring in the mass of one Kerbal):

Propulsion: 1 Rockomax 48-7S

Fuel capacity: 300 units of LFO

Delta V: 4805 m/s

Mass(Full/Dry): 1991/491 kg

Eve Lander:

Pic: https://www.dropbox.com/sc/d1zv1ysdgcx2t6z/AADepwzzQATqK94TtjzuQSNba

For what even the GPL can’t land on, the Eve Lander is an asparagus staged pancake tasked with landing on and returning from only one planet: Eve. With 5 stages and 11 engines, it only has enough Delta V to lift off from Eve’s mountains. To ease the stress of landing it precisely on a mountain, the Eve Lander comes with a detachable wheel base that can be used to drive from initial landing site to a nearby mountain.

Specs(Factoring in the mass of one Kerbal):

Propulsion: 11 Rockomax 48-7S (5 stages)

Fuel capacity: 1855 units of LFO

Delta V(Given that the wheel base and parachutes have been detached): 9419 m/s

Mass(Full/Dry): 13225/346 kg

Parachute Module:

Pic: https://www.dropbox.com/sc/brcqx5xvi64vh57/AAABGANDLWsRwMlj7uCU4meda

Basically, it’s a parachute attached to a docking port. To be used with the GPL to land on atmosphere hosting worlds such as Duna and Laythe, and to be used with the ion lander to return safely to Kerbin once the mission is over.

Xenon Gas Tank Module:

Pic: https://www.dropbox.com/sc/cyy57g1l3mz3cwr/AAAscUBA0EF5s3NmEGPVbPesa

A modular xenon gas tank designed to extend the range of the ion lander. It can be used with the ion lander to ferry the GPL around.

Specs:

Fuel capacity: 3300 units of xenon gas

Supply Ship:

Pic: https://www.dropbox.com/sc/3ejt76ul1hojy0u/AACAH2yQWtQdMyBAz5FlPJJha

The glue of the mission, the supply ship is designed to ferry equipment between planetary systems, refuel the landers, and to restock Jeb on RCS fuel and flags between segments.

Specs:

Propulsion: LV-N Atomic Rocket Motor

Fuel capacity: 2533 units of LFO(300 units of this are for the GPL) and 6000 units of xenon gas

Delta V: 6596 m/s

Mass(Full/Dry): 18761/5495 kg

The fully assembled Sigma Vessel carries 1 of each of all the above equipment and 3 parachute modules. As you can imagine, this mash of landers and modules is not a pretty sight to behold. Unfortunately, I couldn't go for style points here since I was trying to be as efficient as possible.

Pic: https://www.dropbox.com/sc/8f81t8tedwtzjpf/AADD_6-Ng3tXsppcAC9n8vpQa

The mass of the fully assembled vessel is 35,440 Kg, which is less than a Jumbo-64 fuel tank.

The Flight plan:

When designing the flight plan, I had to take the efficiency of each vessel and the fact that I only can carry one flag per segment into consideration. Therefore when it comes to planetary transfers, I want to use the ion lander as much as possible while using the supply ship only where I absolutely have to. For example, it is NOT necessary for the supply ship to transfer to planets without moons such as Moho, Dres, and Eeloo as you only need one flag for each of these planets. On the other hand, it IS necessary to transfer the supply ship to planetary systems such as Duna, Eve, and Jool as you will need more than one flag for each of these systems. Because of this, the supply ship only needs to make three transfers: Kerbin -> Eve -> Duna -> Jool. All the other planets can be handled by the ion lander, the GPL or both. So with this in mind, I constructed a flight plan that included every planet in the solar system. To calculate the Delta V required for planetary transfers, I used this Launch Window Planner, for everything else, I used an excel spreadsheet and a calculator. Now, the flight plan is very “non-linear†so to speak so I created a flow chart to help visualize it.

https://www.lucidchart.com/publicSegments/view/53879cc7-c91c-4c57-81a3-61cb0a0090ac

As a side note, I used this flow chart to calculate the amount of fuel (both xenon gas and LFO) I’d need to carry in the supply ship(I gave myself a 10% error margin on all of the Delta V stats on the flow chart).

Executing the mission:

Originally I had a journal detailing every event of mission as well as sharing some of my thoughts along the way. However, due to the nature of the mission, the journal basically became: “I landed here, lifted off, returned to supply ship†rinse and repeat. So instead of boring you all with a giant wall of text, I documented the mission in 225 pictures spread across multiple Imgur albums.

Lift off and Kerbin System:

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Eve System:

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Moho:

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Forgot the probe core on the supply ship, rescue time!

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Duna System:

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Dres:

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Jool System:

Part 1:

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Part 2:

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Part 3:

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Eeloo:

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Back to Kerbin:

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That's all folks, I hope you enjoyed my little trip through the solar system!

Edited July 6, 2014 by Stratzenblitz75

[TeeGee]

Greetings!

As this is my first post of any significance... -snip- That's all folks, I hope you enjoyed my little trip through the solar system!

You created a spacecraft that visited ALL of the planets in the kerbal system in ONE TRIP??? Wow man. You've mastered KSP.

Did you use a mixture of ion and LV-N?

Edited May 29, 2014 by Vanamonde
Brevity.

[Vanamonde]

This is an ambitious and impressive first post.

However, since it's more mission report-ish than craft share-y, the thread has been moved to Mission Reports.

[Stratzenblitz75]

You created a spacecraft that visited ALL of the planets in the kerbal system in ONE TRIP??? Wow man. You've mastered KSP.

Did you use a mixture of ion and LV-N?

Thanks man! Although, I wouldn't say I've mastered KSP... I'm absolutely terrible at building space planes.

To answer your question; No, I never used the ion engine and the LV-N at the same time, or at least I never planned to. Funny thing is, during the Eve transfer, I actually forgot to turn the ion engine off after I docked the ion lander to the supply ship. It's a good thing that I caught my mistake before I burned through all my xenon gas.

[Stratzenblitz75]

This is an ambitious and impressive first post.

However, since it's more mission report-ish than craft share-y, the thread has been moved to Mission Reports.

Opps... I didn't realize that there was a mission reports section. Thanks for moving the thread, I'll try to post in the correct section next time.

[Specialist290]

Well, this is quite the introductory post. Nicely done! I like how you managed to make such a minimalist design perform an effective "Grand Tour."

[TeeGee]

Thanks man! Although, I wouldn't say I've mastered KSP... I'm absolutely terrible at building space planes.

To answer your question; No, I never used the ion engine and the LV-N at the same time, or at least I never planned to. Funny thing is, during the Eve transfer, I actually forgot to turn the ion engine off after I docked the ion lander to the supply ship. It's a good thing that I caught my mistake before I burned through all my xenon gas.

Blah, spaceplanes aren't hard to build. You've created a mission that can tour the whole solar system in 1 go. I don't know anybody that has done the same.

Also, did you use any mods like deadly reentry during your missions?

[Stratzenblitz75]

Blah, spaceplanes aren't hard to build. You've created a mission that can tour the whole solar system in 1 go. I don't know anybody that has done the same.

Also, did you use any mods like deadly reentry during your missions?

Well for me space planes are hard... I think the largest payload I've ever delivered to LKO using a space plane is less than 4 tons. Considering that I've seen someone deliver 34 tons of cargo to Laythe, this isn't all that impressive. I guess what I meant to say is that I still have a lot to learn in the space plane department...

Also, no, I didn't use deadly reentry or any other mods like that for this mission(else Jeb wouldn't have survived the 7 km/s aerobraking at Laythe). However, I have used them before on a previous save where I attempted to play as a more realistic space program. Unfortunately, I had to discontinue that save because of constant crashing caused by all the mods.

[Stratzenblitz75]

Well, this is quite the introductory post. Nicely done! I like how you managed to make such a minimalist design perform an effective "Grand Tour."

Thank you for the kind words! I guess my efforts to make this mission as efficient as possible paid off somewhat.

[Cmdr. Arn1e]

Agree with the others - nice first post! And well done on completing something I'm too daunted by at the moment... Jool-5 is my limit currently...

[Himynameisjake]

And now I need to relaunch in 23.5, very nice!

[Himynameisjake]

Nicely done, and much more objectively/methodically approached than mine, though I was entertained that we had the exact same flight plan. Mine came from the necessity to dump the heavy landers and my utilization of aerobraking, but still, enjoyed it!

Next time do science along the way, makes it grossly harder.

[Stratzenblitz75]

Nicely done, and much more objectively/methodically approached than mine, though I was entertained that we had the exact same flight plan. Mine came from the necessity to dump the heavy landers and my utilization of aerobraking, but still, enjoyed it!

Next time do science along the way, makes it grossly harder.

Yeah it is interesting how my flight plan turned out similarly to yours despite me not having any prior knowledge of your grand tour. However, when you think about it, its not that surprising as the flight plans we used made the most sense. For example, Eve should be the first target in anyone's grand tour as it is the easiest to get to and you get to dump your heavy eve lander early on. Moho is obviously next because its easiest to get to from Eve. Then its off to Duna for aerobraking and then Dres because its easiest to get to from Duna. So on and so forth...

Gathering science was a consideration when I started planning the mission, but I ended up not doing it because, at the time, I thought it was impossible to carry all the heavy equipment around. Now I know better

I may try to do a grand tour again with science but its unlikely. The stress of one grand tour is enough for me... Anyways, I'm taking a break from KSP in preparation for my realism modded career play-through once 0.24 comes out and all the mods are updated.

[astrobond]

Just... Awesome !!!

[Wavechaser]

I seriously doubt how is it possible to decelerate around Tylo with the tiny ion drive with a poor TWR...