Laythe Capitalism!

[mr_yogurt]

I used to write about fuel efficiency, so I couldn't pass by this. My entry. $95.11 per ticket! (see cost breakdown spoiler below)

-snip-

Cool, our first sub 100 Funds entry!

And also 100th reply!

...COINCIDENCE? I THINK NOT.

I've updated the leaderboard. I'm surprised we haven't seen any modded entries yet.

[Wanderfound]

I've updated the leaderboard. I'm surprised we haven't seen any modded entries yet.

Waiting on the update release so as to use the new spaceplane bits.

[Kulebron]

Thanks for such an interesting challenge! I'm surprised there not many entries at all. Apparently, it's very exhausting to perfect the design, rather than getting a goal at any cost.

[RocketBlam]

So in the case of people who use multiple ships, are the costs of getting fuel to the ships included? I mean, it's one thing to use X amount of fuel in a transfer ship between Kerbin and Laythe, but you have to refuel that ship, right? Getting that fuel off Kerbin costs a lot more than the fuel itself, especially shipping it to Laythe.

[Kulebron]

@RocketBlam: Yes, you have to pay to ship the fuel itself. If you look at our screenshots, Kasuha lifts fuel in another vessel and calculates both its own cost and delivery. I start with fuel that's needed for the round trip, then refuel the interplanetary vessel. Other guys flew the entire round trip in one ship.

The trick is that we use jet engines that have much higher specific impulse (about 10 times more) and this saves a lot of fuel.

[RocketBlam]

@RocketBlam: Yes, you have to pay to ship the fuel itself. If you look at our screenshots, Kasuha lifts fuel in another vessel and calculates both its own cost and delivery. I start with fuel that's needed for the round trip, then refuel the interplanetary vessel. Other guys flew the entire round trip in one ship.

The trick is that we use jet engines that have much higher specific impulse (about 10 times more) and this saves a lot of fuel.

Cool. Can you post your .craft files?

[Kulebron]

Hm. Not for free. I'll write a post with this craft file.

[Aravorn Nighthawk]

I really like the idea of the this challenge....I may take this on....but it will be a while as I am just really getting into this game...and have a while to go to learn. =)

[RocketBlam]

So basically it's going to boil down to whoever spams the most air intakes.

[Nao]

So basically it's going to boil down to whoever spams the most air intakes.

Not quite i think. I have a one ship design (basically a small tweak to my previous SST-LaytheAndBack plane) that could in theory go below 70funds/kerbal at like 8-12 intakes per engine. I just need enough time to fly this... so it's "coming soon tm" T_T

[mr_yogurt]

I've updated the rules to accommodate for the new difficulty options in .25.

I'm excited to see the new entries we'll get with the new parts! I'm expecting epic.

[cadaverific]

Space plane designated US-3D (UtilitySpaceplane-v3revD) SSTLAB capable of transporting 24 lucky kerbals (+1 pilot) in first class.

Here we go with my entry kicking off the modded category:

Javascript is disabled. View full album

This plane requires b9 and KER parts with FAR. I also use TACFB, Kerbal Flight Data, and Kerbal Flight Indicators in flight.

As a SSTO that is capable of landing at the runway recovery funds is not an issue. I did do this in sandbox(don't have a career save i can use atm), but i can just calculate everything myself. Here's the breakdown:

Total plane cost: 100,940 funds

Liquid Fuel: 3197 - 443 = 2754 * .80 = 2203.2

Oxidizer : 3419 - 544 = 2875 * .18 = +517.5

Total cost: 2720.7/24

Ticket Price: 113.4 funds

[Kulebron]

Ticket price dropping to $66 !!!

Will post in a few minutes. Older fleet is sold for $1 Multifora (interplanet), Ployka (kerbin), Vihotka (laythe).

[Kulebron]

Our spacelines made a major hardware upgrade, and now you can fly to Laythe in a more comfortable seat for less money!

Kulebra Spacelines offers round trip for only $66!

I made screenshots of ships at the beginning and in the end of the ciycle. All the additional fuel was loaded onto the Kerbin ship, then was pumped to the other ones. Some fuel was excessive, so in the next cycle I can load less of it. (Which will make me spend even less.)

Javascript is disabled. View full album

In the beginning, I took the new nice parts and made ships sleek and beautiful. But that could not be serious. A non-ugly thing can't fly in space, because it's suboptimal. So I squeezed more out of them: lower CoM, more compact layout which gave less oscillating and lower angular inertia.

Javascript is disabled. View full album

Very cheap and safe flying: aspirating engines to ascent, NERVA for interplanetary. Parachutes and engines secure each other: if parachutes fail, engines will land it safely. If fuel is over, parachutes allow safe crash landing sacrificing only some legs bits.

AIn the end, the ship stands in KSC, ready to be refuelled and launched again. No parts are lost. Parachutes are repacked in EVA.

See technical details (including ascent paths) if you're curious.

Javascript is disabled. View full album

Correction 1: Uploading these screenshots I found out that I was so carefully picturing both aerobraking procedures that both plane change maneuvers screenshots were missed. So here's the tech proof: look at MechJeb readouts and notice that I did aerocapture, but not circularization. That's for a reason: near Ap, velocity is low, and plane change is proportionally cheaper than in Pe/low orbit. At Laythe, SOI is narrow, so high orbit is just 3500Km high, but that was enough to get plane change budget (even in the middle between Pe and Ap) as cheap as 78 m/s for 5 degree rel.inc. On next Pe I circularized the orbit. You may hyperedit to make orbit according to screenshot data and see how plane change is cheap. At Kerbin, orbit Ap was about 11Mm, plane change cost 33 m/s of dv.

Correction 2: you may notice that Kerbin shuttle has nose cones in one screenshot, but not in the others. That was the first attempt, I proceeded only to apoapse and cancelled the flight. After reorganizing the ship (removed some massless parts and these cones) the entire trip was made from that point.

Correction 3: the first docking has a screenshot with an attempt to do it with MechJeb (where LF~=5x). I reloded from quicksave after that and docked manually.

Conclusions:

1. If space plane has TWR >1.3 and you need to space, there's no reason to fly on wings. Just eject into upper atmosphere and save dV.

2. New parts have low drag, which made ascents very cheap, and allowed to get high Gs from engines while getting less drag.

3. New parts drag depends on orientation. I flew them like knife, which gives no lift, but reduces drag by 0.005 points.

4. MechJeb can't land ships with these new parts properly, because it estimates drag coeff to be the same as currently, and prediction oscillates with movement. Fuel is overused tremendously. I just oriented retrograde, aimed my prediction manually, used low thrust for corrections and compared coordinates. A couple radial and normal burns did the job.

5. dV expended is quite close to that of rockets, so it's almost perfect, little improvement margin.

I guess, one can improve this if he uses Duna assists, but that is tricky and limits launch windows to 1 in 3 Earth years.

These were too beautiful for me

Javascript is disabled. View full album

Edited October 19, 2014 by Kulebron

[Kulebron]

Impressive! I tried this once, was quite surprised how it slowed down!

[mr_yogurt]

-snip-

Cool. I did not expect the price to get this low when I first posted the challenge.

Funds are worth a lot of earth money. 1 Fund is likely worth at least a million USD, if we compare to how far earth dollars will get you in space.

[Zorph]

Mad props who everyone who completed this challenge, regardless of ticket price. This was hard!

Anyway here's my entry. I took 24 Kerbals at a time, and used 3240 units of liquid fuel and 3278 units of oxidizer, for a just under $133.

That's not a winning entry, despite my Laythe lander being (I think) smaller. Apparently I just don't know how to fly as well as the top finishers.

Here's my Kerbin lander and interplanetary bus, docked in LKO:

I don't know how to post a series of pictures, so here's a link to the album:

http://imgur.com/a/gurSC

Oh, this is no mod parts, BTW, just the new ones.

[Kulebron]

Cool. I did not expect the price to get this low when I first posted the challenge.

Funds are worth a lot of earth money. 1 Fund is likely worth at least a million USD, if we compare to how far earth dollars will get you in space.

Me neither. Yes, that would be comparable.

By the way, I think it's would be good to mark KSP versions of entries in the leaderboard, because I did this already in 0.25 having better hardware.

[Kulebron]

That's not a winning entry, despite my Laythe lander being (I think) smaller. Apparently I just don't know how to fly as well as the top finishers.

I don't know how to post a series of pictures, so here's a link to the album:

http://imgur.com/a/gurSC

MechJeb is allowed, so it facilitates test process a lot. You did a good transfer with Mün gravity assist and direct Laythe encounter by the way.

Use [ imgur ] tag for albums: [noparse]

Javascript is disabled. View full album

[/noparse]

[mr_yogurt]

Me neither. Yes, that would be comparable.

By the way, I think it's would be good to mark KSP versions of entries in the leaderboard, because I did this already in 0.25 having better hardware.

Ok. I did that.

Although if we compared to fuel cost 1 Fund would be worth less than 1 million USD. Finding a working exchange rate (if one exists) is going to be difficult.

[Kulebron]

Well, I read that Soyuz had launch cost about $70M, and a lot of cost is engine turbopumps. So if we look at it's size engine, like LV-T45 at 950f, the reasonable ratio would be $1000/1f. (20 such engines on one rocket, would be $19M.) Seems within 100% margin error, which is enough for estimates. $66 000 IRL would be about what Virgin Galactic wants for its suborbital flight.

[Zorph]

MechJeb is allowed, so it facilitates test process a lot. You did a good transfer with Mün gravity assist and direct Laythe encounter by the way.

Use [ imgur ] tag for albums: [noparse]http://imgur.com/a/<album id from the url>[/noparse]

Thanks for the tips!

I didn't realize MechJeb was allowed. I've never tried it, but maybe now's the time.

[EvifNam]

I can do this mission for $27 400

[Thunderous Echo]

I will try this, however, I must ask:

Could RSS fit into this in some way?

I'd be going to Laythe-Titan, the largest moon of Dres-Saturn.

Edited November 20, 2014 by Thunderous Echo

[astrobond]

Hi All

Here is my 0.25 "New KLK SSTO 15T" craft file, and the YouTube Video

All stock parts but MechJeb2.

Not intended for this challenge, but with 70880$ cost and 70168$ returned, that makes 356$ for each Kerbal with this "Minibus to Laythe and back" ! lol

And perhaps that could add a badge to my signature ?

.

Edited November 20, 2014 by astrobond