Firemetal

Low mass Eeloo mission

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(Keep in mind this is my first challenge! I'm sorry if its not all perfect!)

The Low Budget Mass Eeloo Mission

Ion engines aren't "low budget"!

 The challenge:

Build a spacecraft, be it plane or rocket, that is under 50 tons maximum.

Rules

1. No Hyper-edit or debug menu of course. 

2. Craft must be stock.

3. KER, Mechjeb and any visual mods and other mods that doesn't add parts are permitted.

4. You may part clip to an extent, just be careful not to do it too much! (i.e clipping an engine into a fuel tank)

5. Craft must be manned.

6. No refueling or ISRU.

Scoring will depend on how light-weight the craft is.

Entry Must have video footage or imgur album that shows:

  • Craft in VAB
  • Ascent 
  • Orbital maneuvers
  • Landing and flag
  • Ascent from Eeloo.
  • Kerbal safely back at Kerbin.

 

Winners!

 

(currently struggling here. Dang mobile type.)

1 Hazard-ish 3.6 tons.

1. DBowman - 4 tons

2. Jetski - 6 tons

3JacobJHC - 45  tons

5 @Der Anfang - 47 tons 

6  - 48 tons

 

I hope this challenge is valid.

Can't wait to see entries!

 

Edited by Firemetal

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Looks valid enough to me, though you should probably at least post your own attempt at it.  Crewed mission there and back without refueling and that weight limit might be at least a little bit tricky, but should be doable.  I might have time to try it later tonight.

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On ‎6‎/‎27‎/‎2016 at 8:29 PM, Hodari said:

Looks valid enough to me, though you should probably at least post your own attempt at it.  Crewed mission there and back without refueling and that weight limit might be at least a little bit tricky, but should be doable.  I might have time to try it later tonight.

I am 100% sure.

This can't be more than 30 tons and it went to Moho which requires a lot more Delta V. You'll definitely need ion engines but it is possible. I'm too lazy to attempt my own challenge. :/ First of all I've never done anything with Ion engines. 2nd I know that they're even slower than nukes. -.- I will attempt it at some point though!

Edited by Firemetal

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1 hour ago, ExtraordinaryKO said:

Ship mass in VAB48.142 t

Ship mass at launch : 46.856 t

Total mission time : T+ 2y, 15d, 19:56:40

I'm sure someone could do a lot better than me, but I'm just happy I did it. :) 

http://imgur.com/a/BQoGX

Nicely done

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1 hour ago, ExtraordinaryKO said:

Ship mass in VAB48.142 t

Ship mass at launch : 46.856 t

Total mission time : T+ 2y, 15d, 19:56:40

I'm sure someone could do a lot better than me, but I'm just happy I did it. :) 

http://imgur.com/a/BQoGX

Congrats! You are the first to complete the challenge! :D Pretty cool launch too.

 

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Working on my entry now, landing on eeloo now. Ship mass is 6.179 tons, using an air breathing stage first, then 2 sparks, then ion pull dragger. Safe return remains to be seen.

Edit: landed on eeloo, and now trying to play a Jool flyby to get home with only 1k dv. Lots of timewarping...

Edited by Jetski

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This is the most convenient challenge ever I just finished building an Eeloo craft under 50 tons. You will have my submission soon. Just a quick question, are you considering a badge? I am going to complete it anyways but I am still curious.

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Done.  

6.321 Tons on pad (not counting launch clamp)

Cost 71335 funds.

MET 26y 293d

Ions can burn for 786ms on a single battery charge, used an RTG clipped inside to recharge in approx 2.5 hours.  Air breathing Whiplash to reach about 25K (burn up then 45 degrees until LF runs out), then Terrier easily makes orbit.  ions for the rest of it, with 3 drop cans of 700 xenon, last one left half full in very eccentric orbit while Val landed and posted her flag. Lots of waiting and warping, used a Jool/Tylo gravity assist to make a return Kerbin intercept for only about 300 ms, burned the last of my fuel to slow enough to make a very hot aerocapture and splashed down on a drogue. @Nefrums or someone could probably shave a bit off this weight, but this is my best :)

Would be rad to have a badge for this, @Firemetal I can make one if you don't want to.

Edited by Jetski

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50 minutes ago, Jetski said:

Done.  

6.321 Tons on pad (not counting launch clamp)

Cost 71335 funds.

MET 26y 293d

Ions can burn for 786ms on a single battery charge, used an RTG clipped inside to recharge in approx 2.5 hours.  Air breathing Whiplash to reach about 25K (burn up then 45 degrees until LF runs out), then Terrier easily makes orbit.  ions for the rest of it, with 3 drop cans of 700 xenon, last one left half full in very eccentric orbit while Val landed and posted her flag. Lots of waiting and warping, used a Jool/Tylo gravity assist to make a return Kerbin intercept for only about 300 ms, burned the last of my fuel to slow enough to make a very hot aerocapture and splashed down on a drogue. @Nefrums or someone could probably shave a bit off this weight, but this is my best :)

Would be rad to have a badge for this, @Firemetal I can make one if you don't want to.

On mobile atm. So I can't give official award but I will do that in the morning! Nice job! Understatement. Awesome job! I don't think I can make a badge on my own but if someone can help me with that, I'd do it! 

Again great job! :D

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Finally my entry is done. I am proud of this video. :)

 

 

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On 6/28/2016 at 0:29 AM, Firemetal said:

Mechjeb and any visual mods and other mods that doesn't add parts are permitted.

[wise guy voice] Accually Mech Jeb adds a part And KER

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1 hour ago, Gauga159 said:

[wise guy voice] Accually Mech Jeb adds a part And KER

Ik that. Mech Jeb computer is aloud. :P

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12 hours ago, JacobJHC said:

Finally my entry is done. I am proud of this video. :)

 

 

I am on mobile again. Anyway congrats to jacobJHC for completing the challenge! Will add you to the leaderboard later.

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On ‎6‎/‎30‎/‎2016 at 6:59 PM, Jetski said:

Done.  

6.321 Tons on pad (not counting launch clamp)

Cost 71335 funds.

MET 26y 293d

Ions can burn for 786ms on a single battery charge, used an RTG clipped inside to recharge in approx 2.5 hours.  Air breathing Whiplash to reach about 25K (burn up then 45 degrees until LF runs out), then Terrier easily makes orbit.  ions for the rest of it, with 3 drop cans of 700 xenon, last one left half full in very eccentric orbit while Val landed and posted her flag. Lots of waiting and warping, used a Jool/Tylo gravity assist to make a return Kerbin intercept for only about 300 ms, burned the last of my fuel to slow enough to make a very hot aerocapture and splashed down on a drogue. @Nefrums or someone could probably shave a bit off this weight, but this is my best :)

Would be rad to have a badge for this, @Firemetal I can make one if you don't want to.

Holy shnizzle

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@Firemetal thanks for the challenge - nice and simple goal, complicated set of trade-offs and challenges. My entry is LEeloo (Lite Eeloo), 5.257 ton:

notes:

  • If I could figure out an ascent that used 9 less liquid fuel I could drop 750 kg, I'm sure a real pilot could do that, maybe something with wings?
  • There is some gravity assist magic one could use to reduce deltaV to Eeloo, the initial circularization burn is 800 m/s on ion. I can see maybe it's possible to drop 70-140 kg of Xe.
  • I liked my Xe drop stage; stack attach a decouple to the ion, radial attach Xe to that, use the position tool to move the decoupler up so it makes a sleeve for the ion nozzle - then engine thrusts, it's mechanically plausible, and none of the parts clip.

here is the craft:

3HUWUAbl.png

 

@Firemetal I had a a couple of ideas for extensions or versions of the challenge:

  • A life support version (with living space/capsule requirement) - would really challenge time vs deltaV / mass. Maybe allow multiple craft (total mass) so you could pre send stuff slow and low dv (like Mars Direct)
  • a KAS division - so you can disassemble the the bits you don't need anymore - like the steamer in Around the World in Eighty Days, not sure if it's be 'fun' but probably would bring the mass down more.
Edited by DBowman
imgur is messing with image linking or something

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7 hours ago, DBowman said:

@Firemetal thanks for the challenge - nice and simple goal, complicated set of trade-offs and challenges. My entry is LEeloo (Lite Eeloo), 5.257 ton:

notes:

  • If I could figure out an ascent that used 9 less liquid fuel I could drop 750 kg, I'm sure a real pilot could do that, maybe something with wings?
  • There is some gravity assist magic one could use to reduce deltaV to Eeloo, the initial circularization burn is 800 m/s on ion. I can see maybe it's possible to drop 70-140 kg of Xe.
  • I liked my Xe drop stage; stack attach a decouple to the ion, radial attach Xe to that, use the position tool to move the decoupler up so it makes a sleeve for the ion nozzle - then engine thrusts, it's mechanically plausible, and none of the parts clip.

here is the craft:

3HUWUAbl.png

 

@Firemetal I had a a couple of ideas for extensions or versions of the challenge:

  • A life support version (with living space/capsule requirement) - would really challenge time vs deltaV / mass. Maybe allow multiple craft (total mass) so you could pre send stuff slow and low dv (like Mars Direct)
  • a KAS division - so you can disassemble the the bits you don't need anymore - like the steamer in Around the World in Eighty Days, not sure if it's be 'fun' but probably would bring the mass down more.

Congrats! A life support system version would be significantly harder because life support adds mass and people can't minimize the mass as easily making heavier crafts all together. No total mass either. If someone wants to do one with life support, I'll totally allow it but it must be under 50 tons! KAS is an interesting idea. I'll think about it.

Awesome entry and thanks for the suggestion!

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@DBowman fantastic job!  You beat my weight nicely. Going solar, tighter Xe margins and that epic water landing seem to have done the trick. Also good call on decoupler instead of docking ports, every kg matters.  Did I see no parachute at all?

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5 minutes ago, Jetski said:

@DBowman fantastic job!  You beat my weight nicely. Going solar, tighter Xe margins and that epic water landing seem to have done the trick. Also good call on decoupler instead of docking ports, every kg matters.  Did I see no parachute at all?

Yup he used the eject strat. I remember back in the day when I was completely new, I remember jumping out and surviving a fall from about 10km after my parachute failed. I was confused to say the least. :D

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@Firemetal I was thinking to put the life support entries in a totally separate category - because the challenge is so much different. Who knows if it's even possible under 50 ton. Maybe add a 'hab' requirement, some other challenges require two crew slots per crew for 'long duration' missions - and Eeloo would sure qualify.

@Jetski thanks. For a low mass Mun challenge I worked out that hitting the water at 37 m/s was like jumping from 57 m - the world record jump into water is a little less than 60 m ( crazy ), so it looks 'really doable IRL' without a chute at all.

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2 minutes ago, DBowman said:

@Firemetal I was thinking to put the life support entries in a totally separate category - because the challenge is so much different. Who knows if it's even possible under 50 ton. Maybe add a 'hab' requirement, some other challenges require two crew slots per crew for 'long duration' missions - and Eeloo would sure qualify.

Eh maybe but I don't know anything about TAC but I might. You see I knew that doing Eeloo and back under 50 tons is possible. I even thought it too easy for some which is why I didn't do it myself. (Laziness overload) But under 50 tons with life support is a different story. I'd have to test if its possible which means downloading a mod I'm not even interested in. If one of you guys do it, maybe I'll add another category for life support. Thanks for the suggestion though.

Also I have a craft that doesn't use Xenon... It is about 40 tons and is a mk1 SSTO. I'm thinking about it. I only just launched a functional SSTO to Duna and back for the first time and Eeloo would be a lot harder. But I may do it just to break a record, :)

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@Firemetal The Jool 5 Challenge has outstanding longevity; partly I guess that because Jool system is so beautiful - but also because it has a variety of kinds of challenge under the one umbrella. There are a couple of Duna challenges (DERP & Duna Permanent Outpost Mission Architecture) where LS upped the ante in a good way. Anyway up to you obviously, just putting it out there.

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2 minutes ago, DBowman said:

@Firemetal The Jool 5 Challenge has outstanding longevity; partly I guess that because Jool system is so beautiful - but also because it has a variety of kinds of challenge under the one umbrella. There are a couple of Duna challenges (DERP & Duna Permanent Outpost Mission Architecture) where LS upped the ante in a good way. Anyway up to you obviously, just putting it out there.

Yes but those are not low mass challenges. I know Jool 5 has a low mass section but I doubt that life support would fit in a low mass challenge. What you do in a low mass challenge is try to exploit the things you can do with low mass parts. This means low funds, low part count (lol forget that you put like 50 batteries on yours (still counts tho)) and low mass. This is unrealistic as is a lot of stuff in KSP (even though a lot is to be fair) and life support makes what is unrealistic, realistic and people can't build 5 ton rockets to go to various planets and back. There is a lot more planning that goes into it. DERP and Duna Permanent Outpost Mission Architecture is not a low mass challenge.

Thanks for the suggestion though.

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Hi @Firemetal I made a second attempt with wings - 4.290 ton.

kD6XJ5e.png

album embed may be borked just now the album is http://imgur.com/a/ONtL7

 

  • Wings: the natural way to use a jet. Big-S Wing Strake has the mass of a wing but with
    LF tank built in
  • Stage the under carriage for minimum drag - it doesn't have to land
  • Jet: I used a dedicated atmosphere only Panther engine - less mass & less to orbit than a RAPIER
  • Flight Path:
    • heading & launch time to get into an inclined orbit to match a reference burn (see album)
    • climb at pitch 35 in 'dry mode'
    • ease back to pitch 15 as atmosphere thins and thrust drops
    • at 9km turn on after burners
    • at 500 m/s pitch up shooting for 45 just as LF runs out and (engine - drag - gravity) = 0
    • stage away wings + Jet
  • LF Rocket: burn hot & hard, got to be careful re aerodynamic forces & shock heating
  • Ion:
    • pop a high Ap to give time for ion circularization
    • for Kerbin depart split the burn into two (see album)
  • Gravity Assists:
    • Kerbin - Eeloo: I saw @PLAD low dV to Eeloo Challenge and reproduced on of his 'simpler' KEKJEe paths 2344 m/s to Eeloo surface
    • Eeloo - Kerbin: While playing around I lucked onto a EeJK trajectory. For this entry I used @PLAD Fly by to find an EeJK & then seat of the pants added another K to reduce capture dV from 1300 to 1000 m/s
  • Aerobraking: 900 m/s saved on K circularization. Just set a safe Pe, for me in a cmd chair around 64km, add a Pe
    node and keep warping to node. Orbits decay fast at the end
  • EVA splashdown: A Kerbil terminal velocity can be reduced to a survivable (water impact) velocity with the jet pack.A
    chute is like 10% the mass of the whole vacuum craft, cannot afford it

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