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Payload Efficiency Challenge

Right

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Right

Right

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Posted (edited)

Derived from mhoram's Payload Fraction Challenge.

Mission Description

Design a launch vehicle with the highest payload cost efficiency and bring it from the launchpad to a Kerbin-orbit with a periapsis of 75km or higher.

Scoring

Calculate the payload cost efficiency as total ship cost before liftoff minus payload cost minus recovered funds divided by payload mass in orbit; AKA

(Total ship cost - Payload Cost - recovered funds)/Payload Mass. The lower the value, the better.

Restrictions

  • No cheating, debug console, part clipping, infiniglide
  • No participation of the payload in the ascent
    • No engines in the payload (Xenon and RCS also count as engines)
    • Fuel tanks in the payload must reach the orbit full (LiquidFuel, Oxidizer, XenonGas, MonoPropellant and SolidFuel)
    • No excessive usage of torque in the payload (explanation)
    • The cost and mass of all lift surfaces applies to the launch vehicle, and not the payload.

    [*]Drag coefficient of the payload must be 0.2 or higher

    [*]Stock KSP V0.90 (MechJeb, KER, & other Info Mods OK)

    [*]Use of FAR, or NEAR will go under modded designs

Submissions

A valid submission must contain at least the following information

  1. Payload mass
  2. Launch vehicle cost at launch (ship cost - payload cost)
  3. Part count
  4. Picture of the ship in the VAB/SPH
  5. Picture of the ship after reaching orbit and decoupling the propellant (periapsis altitude, payload mass & resources-tab must be visible)
  6. If the final stage is recoverable, you may calculate 100% return of the stage if you either:

    A.) Show that the stage has at least 1 radial chute per 10 tons (empty), control, torque, and enough dV to deorbit after decoupling the payload

    B.) Or show picture of the stage landed at KSC after delivering the payload


  7. Documentation of the drag coefficient of the payload either by displaying it in MechJeb (Vessel -> Drag coefficient) or by submitting the payloads craft file or detailed pictures of the payload must be provided where each individual part (in this case keep the number of low drag parts small) is recognizable

Entries which use jet engines will be listed in a separate category

Awards

MechJeb Compliance Award

MechJeb can bring this ship into orbit without human interaction. To qualify for this award state that MechJeb was used and submit a screenshot of MechJeb's ascent path editor. After launch no human interaction is allowed while the periapsis is smaller than 74km.

Tech Level [1, 2, 3, 4, 5, 6, 7] Award

This craft requires a maximum tech level of [#] to build. (Use the advanced filtering mode on your build parts panel)

Leaderboard

Rocket-Engine Designs

Light Category (Payload < 10 ton)

  1. (8.942 Tons, 20 Parts)
    MechJeb Compliance Award

  2. (1 Tonne)
    "Kinda" MechJeb Compliance Award

Medium Category (10 ton <= Payload < 100 ton)

  1. (20.84 Tonnes, 25 Parts)
    MechJeb Compliance Award

  2. (26.3 Tonnes, 35 Parts)
    MechJeb Compliance Award

  3. (50.8 Tonnes)

  4. (36 Tonnes, 29 Parts)

  5. (18.4 Tonnes)
    MechJeb Compliance Award

  6. (41.4 Tonnes, 73 Parts)

Heavy Category (100 ton <= Payload)

  1. (137.3 Tonnes, 107 Parts)

  2. (102.5 Tonnes, ~100 Parts)

Jet-Engine Designs

Light Category (Payload < 10 ton)

  1. (6.765 Tonnes, 19 Parts)

  2. (0.065 Tonnes, 17 Parts)

Medium-Heavy Category (10 ton <= Payload)

  1. (144 Tonnes, 184 Parts)

  2. (32.2 Tonnes, 240 Parts)

  3. (82 Tonnes)

Modded Rocket Designs

  1. 631 Funds/tonne - Pamynx (21.6 Tonnes) [FAR, DRE, RT2, ProceduralFairings]

Modded Jet Designs

  1. 151.56 Funds/tonne - kcs123 (32.25 Tonnes, 98 Parts) [FAR, B9, B9PWings, Adjus. Landing Gear]

Edited by Right
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astrobond

astrobond

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Hi Right :)

Don't know if this is ok for this challenge, but for my next Biomes Catcher mission to Eeloo, i wanted to try my new MK3 SSTO Plane as lifter...

Very versatile and easy to fly, full stock + KER

36 Tons max payload (tested with the big orange tank... without pictures lol)

275893 Funds, 56 Tons without Payload, 240 Parts

For this mission, the payload was 32.2 Tons in Spaceplane Hangar

Cost to lift the payload at 90km: 275893-274880=1013 Funds

1013/32.2=31.46 funds/ton

Here is the album:

Javascript is disabled. View full album

Fly safe with Jeb !

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Right

Right

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Hi Right :)

Don't know if this is ok for this challenge, but for my next Biomes Catcher mission to Eeloo, i wanted to try my new MK3 SSTO Plane as lifter...

Greetings! Well your payload does have RCS thrusters on board which is prohibited. However, since you're not evidently offering your most competitive possible entry (90k Peri, larger theoretical payload) I will go ahead and tentatively list it. Besides, it has great style! ;)

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hoioh

hoioh

Posted
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So I thought it might be a good idea to go light, but that was a mistake. So here is a not so very competitive entry which is ultra light (below 3 tonnes). Used Mechjeb, but when using jets the ascent guidance isn't worth a penny, so no full autopilot ascent.

Javascript is disabled. View full album

Payload mass: 0.065 tons (this is where the high cost/ton comes from)

Total vessel cost: 29.273 Kerbuck$

Payload cost: 17.770 Kerbuck$

Vessel cost: 11503 Kerbuck$

Recovered funds: 11430 Kerbuck$

Sum total cost of mission: 73 Kerbuck$

73/0.065 = 1123 Kerbuck$/ton

So, not so very competitive due to the super low mass.

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Laie

Laie

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Are tankers allowed? In that case, I could offer this:

RBT_05.jpg

-> craft file <- (requires Mechjeb)

Launch cost: 796820

Recovery: 268594 + 367461 = 636055

Launch - Recovery: 160765

Cargo was 234 tons of fuel, worth 21481.2 funds on the ground. That leaves me with a net cost of (160.7k - 21.5k) / 234 = 595 funds / ton. It might be possible to make mechjeb perform just the right ascent profile, but I won't even try. So: not MJ-compliant.

To summarize: 234 tons @595funds/ton, 156parts on the pad, 68 parts in orbit. Sustainable.

Edit: according to my notes this Jet-driven tail-sitter should come to ~26funds/ton. However, I'm controlling it through kOS. Submit or not?

Edited by Laie
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ttnarg

ttnarg

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So I had a go at this, didn't get an amazing cost per ton (for jets) nor did I get into the 100+ ton range like I was aiming for :-(. I used Jets but no wings. Had a flight path of a rocket not a space plane. If you recover @ 100% then the cost is the fuel you use I'm guessing space planes use a lot less fuel. Which is why my cost per payload ton is not amazing.

Here are the numbers. Will try and post pictures tomorrow.

Total Rocket Cost 452,867 (190 parts)

Payload cost 22,800 (1 part)

Lift cost = 430,067 ( 452,867 - 22,800 ) (189 parts)

Recoved Funds = 409,868 (189 parts recoved for 100% at the runway)

Net cost = 20,199 ( 430,067 - 409,868 )

Payload Ton = 82

Cost per Ton = 246.33 ( 20,199 / 82 )

100% stock, no MJ, Landed by hand using 12 Parachute and Jets.

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GoSlash27

GoSlash27

Posted
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Here's one that I made a while back for a different challenge:

http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Lifter-Ception

http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Lifter-Ception/Flight

It ran $32 a tonne for a 20+ tonne payload, but I'll have to rerun the mission to make it legit.

I also have a pure rocket SSTO I made to assist another member that completed this challenge. 41 tonne payload to 75x75 orbit at $580/ tonne.

Sounds like I've got a lot of flying/ documenting to do this weekend!

Best,

-Slashy

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Right

Right

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Since this is a design oriented challenge, I've made the requirements for recovery more lenient. Basically, just show that your final stage is recoverable and you may calculate 100% of funds for that stage, empty, as recovered. This removes the burden of needing a career mode with all science unlocked, and of often painstakingly flying your ship back to KSC.

So I thought it might be a good idea to go light, but that was a mistake. So here is a not so very competitive entry which is ultra light.

I think you have the right idea actually. Optimize payload cost on a small craft, and then scale it up with similar ratios. As for your craft, I'm betting you would be able to bring that number up a lot if your craft's total mass was closer to 10-12 tons, with some of that being extra fuel, but mostly payload.

Are tankers allowed? In that case, I could offer this:

-> craft file <- (requires Mechjeb)

Edit: according to my notes this Jet-driven tail-sitter should come to ~26funds/ton. However, I'm controlling it through kOS. Submit or not?

I like the design of the first stage, as well as the coordinated multistage recovery! Unfortunately neither of these crafts have a dedicated payload. As a result, its hard to apportion the true cost of the payload since they depend on a receptacle vessel already in orbit. With a little tweaking, they should be able to provide similar cost efficiency while complying with the restrictions.

Rules aside though, that is a very efficient fuel delivery vehicle!

Will try and post pictures tomorrow.

Looking forward to it!

Medium Category entry:

http://youtu.be/ykp5hMA0IWk

You fly with the earmarks of one who has piloted many-a-payload to LKO haha. You're entry does not meet the 75k periapsis requirement. However, since you obviously had plenty of fuel to spare (and which was ultimately dumped just before landing), I think we can assume that it would not have been an obstacle for your craft. In fact, thanks to your detailed documentation, I'm going to recalculate your score based on 100% recovery (empty) since its clear you easily could have landed on the pad. :wink:

Here's one that I made a while back for a different challenge:

http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Lifter-Ception

Haha, great choice for the payload. Better believe that scores kerbals will step into ships built by the lowest bidder.

I read a great post by you at some point recommending the ram air intake based on their superior intake and drag. Might give that craft a bit more through?

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GoSlash27

GoSlash27

Posted
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My entry for rocket power:

http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Efficiency%20LFB

41.4 tonne payload

$109,442 booster at launch, $80,971 recoverable (not counting the leftover fuel)

$687.81/ tonne.

AFAIK it's fully MechJeb compliant since it's launch profile is a standard gravity turn. It's also fully sustainable (nothing left in orbit but the payload).

It's a start...

Best,

-Slashy

*edit* Wikisend doesn't seem to be working. I trust you'll take my word for it... :(

- - - Updated - - -

Haha, great choice for the payload. Better believe that scores kerbals will step into ships built by the lowest bidder.

I read a great post by you at some point recommending the ram air intake based on their superior intake and drag. Might give that craft a bit more through?

Kerbals don't actually ride the mass- lifter. It's just used to put outsized and heavy payloads into orbit for assembly. My kerbals ride spaceplanes for safety.

I just used hitchhiker pods for that lift to show there was no way to cheat.

I'll rerun the launch to verify it this weekend.

Best,

-Slashy

Edited by GoSlash27
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Laie

Laie

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its hard to apportion the true cost of the payload since they depend on a receptacle vessel

Huh? Weight before docking. Weight after. Multiply difference by cost of fuel (91.8funds/ton).

Tankers *are* easier, though, because it's a flexible payload. Launch went better than expected? Great, the payload has just increased.

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ttnarg

ttnarg

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I didn't read the bit about having to get to 75k so I guess this dose not count. If I had known that I thing I would of had the fuel to make it but it would be very close. It would of left me with such a week deorbit burn that I might of needed an orbit or 2 of air breaking before landing and that would of made it all but imposable to get back to the KSC. But this was my first try with this craft if I try again I think I could do it just need a little better flight up.

Here are the pictures anyway. Might try again if I have time.

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SanderB

SanderB

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Mid Level Booster range:

Mechjeb & sustainable compliant and 75km periapsis to boot!

Payload: 18.385t

Booster Cost - Recovery: 87,620 - 74,352 = 13,268

Cost / t: 721.68

Fuel Cost: 11,750

Fuel cost / t: 639.11.

I think it is fair to go with 639.11 kredits/t considering how close I got to the launchpad :P.

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ttnarg

ttnarg

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Getting 100% with out a powered landing is hard: Aim to fly over the runway (it long so much easier then the launchpad); Quick save a little way out; Then it just a case of timing your parachutes.

(I landed on jets which has it own problems but does mean I can fly around a bit to get my landing where I want it.)

PS I've been thinking of doing landings on wheels then having a solar powered truck with a Klaw to pull it onto the runway to get 100%.

Edited by ttnarg
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SanderB

SanderB

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(intended for the <1t entry even though it is precisely 1t.)

Payload: 1.00t

Fuel: 1193 Kredits

fuel cost / t: sorry idk, math too hard!

Recovery on launchpad.

Kinda MJ compliant (Someone has to turn off the main engine at vessel mass ~12t), sustainable compliant, lands on landing legs (which are wholly reusable without needing to be repaired) and reaches a 76km periapsis.

I think i have MJ assisted precision landing down pretty well now. Just have to make sure that the latitudinal prediction is on target and that the longitudinal prediction is a little over the target by half an arcminute, and just gradually retrothrust while descending to bring it more on target as it fluctuates less and less.

Next up: 0.1t and 10kg entries.

Edited by SanderB
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Laie

Laie

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Getting 100% with out a powered landing is hard

Nearly impossibe / not worthwhile, I'd say. In order to not blow up the runway, you have to come down reeeaaally slow. Requires an insane amount of chutes (reducing your payload), or a powered landing. See my first entry for how it doesn't work.

That said, here's another:

Two-Stage_01.jpg

(/ (- 1041060 271134 573667 69450) 245.99) -> 515.5 funds / ton.

Sustainable, not MJ-compliant.

Slight problem: I was using Vernors for RCS and these things have tapped the payload. Not much, but it happened.

Also notable, I still had 6t of fuel in the tanks when I returned. In case of a tanker, most of that would have been delivered and the cost would have improved by another ~10funds/ton. Not allowing tankers is probably better for the challenge.

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ttnarg

ttnarg

Posted
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Nearly impossibe / not worthwhile, I'd say. In order to not blow up the runway, you have to come down reeeaaally slow. Requires an insane amount of chutes (reducing your payload), or a powered landing. See my first entry for how it doesn't work.

There an option for that when you start the game which this challenge dose not forbid :-P but your right I was not counting a short blip of engine power right before touch down.

245.99 ton? Nice. I was looking at a 2 stage craft for 100ton+ this lunch time but didn't get it to fly before I had to go back to work.

Edited by ttnarg
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Laie

Laie

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Slashy, I raise you one:

Slashy_plus.jpg

That's basically your vessel, plus a little extra. Lost equipment has increased by one SRB, reduced by several decouplers.

Net launch cost, after recovery and not counting the payload, is 26419 funds for 50.8 tons, or 520 funds/ton. Sustainable and MJ-compliant.

No proper gallery was made; when launched according to the given profile, it will have ~190m/s left for recovery. As it requires a powered landing, don't spend more than ~120m/s on the de-orbit burn.

->craft file<-

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Right

Right

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My entry for rocket power: http://s52.photobucket.com/user/GoSlash27/slideshow/KSP/Efficiency%20LFB

*edit* Wikisend doesn't seem to be working. I trust you'll take my word for it... :(

The pictures suffice :)

Huh? Weight before docking. Weight after. Multiply difference by cost of fuel (91.8funds/ton).

Tankers *are* easier, though, because it's a flexible payload. Launch went better than expected? Great, the payload has just increased.

My point was that the receptacle vessel cost money to get into orbit, and that cost is not being factored into the efficiency.

Other than that though it appears to me they possess no inherent advantage (I don't consider convenience as one) over a craft with a dedicated payload. However, I hope you will forgive me if I still don't permit them simply because it would add another layer of exceptions and counter-exceptions to the rules.

As to the question about kOS, I don't think I see a problem with it. Is there any conceivable situation in which it would give a higher theoretical efficiency?

Excellent results on the second entry! I think your multistage recovery techniques will be the key to the best efficiencies for rockets. I'll look past the RCS thing, its SO minimal I doubt it would even make a difference to the accuracy we're measuring.

I wonder, do you think using an even steeper ascent and landing the first stage at KSC would improve the score? Would require more fuel, but probably not more than the extra 4% you would get.

I didn't read the bit about having to get to 75k so I guess this dose not count.

Looks like you had enough fuel to push the peri up and still deorbit. Proof enough for me. Besides, I'd rather you spend time seeing if you can improve or redesign than fly things again and again. You're welcome to set up a tow truck for fun! As the OP says though, you can assume 100% recovery if its clear you can potentially land it.

Mid Level Booster range:

(intended for the <1t entry even though it is precisely 1t.)

Entries look good! Good tip about the landing. I'm thinking about putting some wings on my designs so I can have a bit of glide ability before chuting.

Also, I would have loved to see your face while you were landing the entry #4. Fuel ran out just before reaching the ground and it looked grim for those nuke engines haha.

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Right

Right

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If anyone wants to give partial credit for a craft to someone else, let me know and I'll list more than one name.

What about making if with FAR and DRE ?

Well I am lazy and do not want to uninstall those addon to see what my launcher are worth ;)

Sure, I'll set up a bracket for modded entries. For now it will be pretty catch all, but if we get enough entries I will set up multiple categories like stock.

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