I traveled to Eeloo's surface and back using 1 fuel tank

[Red Iron Crown]

What happened in this thread? The video looks legit to me, there's no evidence of tank clipping or infinite fueling that I can see.

Please drop the cheating talk, now please wait a moment while I clean all the bickering out of this thread.

Edit: There, all cleaned up. Please play nice, people.

Edited May 28, 2017 by Red Iron Crown

[KAL 9000]

@JacobJHC If it's real, I apologize. It looked a little fishy to me, and I may have been wrong. 

I hope this doesn't negatively impact your credibility as a YouTuber and forum user, and I look forward to seeing more from you in the future.

[JacobJHC]

2 minutes ago, KAL 9000 said:

@JacobJHC If it's real, I apologize. It looked a little fishy to me, and I may have been wrong. 

I hope this doesn't negatively impact your credibility as a YouTuber and forum user, and I look forward to seeing more from you in the future.

Don't worry about it. Currently I am attempting another challenge involving Eeloo and I made sure the ship had similar delta-v levels to prove that the mission can work. Thanks.

[John FX]

On 28/05/2017 at 11:36 PM, Red Iron Crown said:

What happened in this thread? The video looks legit to me, there's no evidence of tank clipping or infinite fueling that I can see.

Please drop the cheating talk, now please wait a moment while I clean all the bickering out of this thread.

Edit: There, all cleaned up. Please play nice, people.

Wait, I read the cleaned thread?

Sheesh, there really is not much in KSP a skilled player cannot do with 10Kdv, except land on larger planets with no atmosphere, like tylo.

Video looked fine to me, just because someone else can do something you cannot is no reason to accuse them of cheating.

[Matt Lowne]

On 2017-5-27 at 9:13 PM, KAL 9000 said:

Not to offend, but this is probably fake. No gravity assists whatsoever, and @Matt Lowne has a video showing that @hazard-ish couldn't have gone to Tylo, which is closer, with a single fuel tank using gravity assists. The Delta-V requirements are just too strict.

Tylo is not analogous to Eeloo at all. It's much easier to go to Eeloo than to Tylo. Not to detract from this video, just weighing in that it's not the same. My "Debunk" video was created using complete mathematical evaluation of every point of the mission. If you want to make serious accusations of faking then you need to at least crunch the numbers. And this doesn't include personal anecdotes. I haven't watched the video to the extent that I'd be willing to support one view or the other, but just from the concept alone I would expect this to be possible.

[Chel]

What about a handy thing called 'launch windows'? Eeloo spends most of it's time very far from Kerbol, but it also intersects Jool's orbit as well. Waiting until Eeloo is there saves fuel, and makes it easier to get an encounter.

[Zhetaan]

*Stops the video*

*Replays the video*

*Replays again*

Wow!

I have a few questions:

1.  What's the story behind that wing profile?  You added some weird admixture of dihedral angle and I-don't-know-what for stability, obviously, but I would have expected a lot more flexure from that many wing parts.  Autostrut, I assume?

2.  311+ years?  I'm interested to know why you picked the transfer windows you did.  I'll guess that the reason has to do with Eeloo's eccentricity having a more pronounced effect on the efficiency of certain transfer windows over others, but I'd like to know what you have to say on the subject.

3.  I really liked your landing leg solution to take-off.  I was wondering whether you were going to try to stand the thing up on the engine bell and just jetpack up and down, or do something else, but I wasn't certain whether your reaction wheel module had enough torque to move that thing around.  What gave you the idea?

4.  How was your final?

[JacobJHC]

30 minutes ago, Zhetaan said:

*Stops the video*

*Replays the video*

*Replays again*

Wow!

I have a few questions:

1.  What's the story behind that wing profile?  You added some weird admixture of dihedral angle and I-don't-know-what for stability, obviously, but I would have expected a lot more flexure from that many wing parts.  Autostrut, I assume?

2.  311+ years?  I'm interested to know why you picked the transfer windows you did.  I'll guess that the reason has to do with Eeloo's eccentricity having a more pronounced effect on the efficiency of certain transfer windows over others, but I'd like to know what you have to say on the subject.

3.  I really liked your landing leg solution to take-off.  I was wondering whether you were going to try to stand the thing up on the engine bell and just jetpack up and down, or do something else, but I wasn't certain whether your reaction wheel module had enough torque to move that thing around.  What gave you the idea?

4.  How was your final?

First off I am glad you liked the video.

1. For the wings I just spammed them until I could get the center of lift where I wanted it, that's why they were shaped weird. At least it looked cool. Yes I did use autostrut, it is my best friend. I probably didn't need it and normal struts would have done the job but it has become habit since my large ships need autostrut so that they can be firm and not kill frame-rate.

2. My launch window was so that I would have an orbit that would get a Jool encounter one of the nodes for Eeloo's orbit so I could almost match Eeloo's orbit using Jool. 

3. Thanks. I knew I was tight on fuel to begin with so I tried to find the lightest way in terms of mass to right the craft. I originally tried airbrakes but those kept poofing away and I would crash the craft instead of liftoff. I then remembered how the large landing legs would flip when they open and I though "hey if these things flip maybe I can have one flip me into the air".

4. Pretty good I think. Thanks for asking. 

[Starman4308]

Did you ever consider something like having one of your two LV-Ns on a separate decoupler, so that you could remove that mass once you no longer needed the thrust?

EDIT: Also, to elaborate a bit for some people: the reason why Tylo is harder than Eeloo is that you can use gravitational slingshots to enter an SOI with arbitrarily small relative velocity for free*, but once inside the SOI, there are hard limits on how much delta-V you have to spend to land and return. For Tylo, you're talking ~6 km/sec bare minimum to land and return, versus just 1.6 km/sec for Eeloo.

So, with smart gravity assists, you can get to Tylo and Eeloo with similar amounts of delta-V, but orbit insertion, landing, and return is much more difficult for Tylo than Eeloo.

*Assuming infinite patience and precision. In practice, you're going to be somewhere above this theoretical lower bound.

Edited June 3, 2017 by Starman4308

[Alpha 360]

Great job! I love to support the 'newer' players(since I only played for a year) and this is awesome! I have hardly gotten out of Kerbin's SOI, and so something like this is amazing! Keep up the good work.

[Regor]

Words cannot explain how amazed I am! Wow! Just Wow!

[JacobJHC]

1 hour ago, Starman4308 said:

Did you ever consider something like having one of your two LV-Ns on a separate decoupler, so that you could remove that mass once you no longer needed the thrust?

 

I did not consider that, ditching one of the nervs would boost the craft's range by quite a bit. Although I am not sure if the reaction wheel would be powerful enough to counteract the offset thrust. I might look into that real quick.

[Starman4308]

8 minutes ago, JacobJHC said:

I did not consider that, ditching one of the nervs would boost the craft's range by quite a bit. Although I am not sure if the reaction wheel would be powerful enough to counteract the offset thrust. I might look into that real quick.

Now that I think about it more carefully, you could have the second LV-N angled through CoM. It'd be curious to see; dropping the second LV-N early would increase gravity losses landing on Eeloo, but takes a significant chunk out of your dry mass.

[JacobJHC]

13 minutes ago, Starman4308 said:

Now that I think about it more carefully, you could have the second LV-N angled through CoM. It'd be curious to see; dropping the second LV-N early would increase gravity losses landing on Eeloo, but takes a significant chunk out of your dry mass.

It would although in my testing I had to use 2 engines since the craft, if fueled to a certain point, cannot use a single engine to land. I didn't know how much fuel I would have when I got there and I didn't want to risk it.

[Superfluous J]

On 6/1/2017 at 10:05 PM, The_Cat_In_Space said:

Eeloo spends most of it's time very far from Kerbol, but it also intersects Jool's orbit as well. Waiting until Eeloo is there saves fuel, and makes it easier to get an encounter.

Actually this is not true. It costs drops of fuel to burn up to Eeloo's apoapsis vs it's periapsis (from LKO) but out there Eeloo is moving slower, so you have to speed up less to match its speed.

Same with Moho, only opposite. You want to meet it near its periapsis as it's going faster and you need to slow down less.

[Firemetal]

On ‎5‎/‎28‎/‎2017 at 3:55 PM, The Moose In Your House said:

still, not enough.

It is. Seen Matt Lowne's Argus to Eeloo? Or Mark Thrimm's SSTO to Eeloo? It can take a lot less DV than 10k DV to get there and back. Legit imo.

Fire

[NSEP]

Seeing the replies on this topic is sad. I believe this is very real, but Matt Lowne's debunking video made all hell break loose. Tension is high, but its not a cold war. I really hope not to see more drama in the future.

Drama aside, nice video. 311 Kerbin years is quite alot! 

[xendelaar]

cool video and impressive work! i don't think i would be able to replicate this ( because i lack the skills) so i can only applaud your accomplishment good sir. 

[John FX]

On 02/06/2017 at 3:05 AM, The_Cat_In_Space said:

What about a handy thing called 'launch windows'? Eeloo spends most of it's time very far from Kerbol, but it also intersects Jool's orbit as well. Waiting until Eeloo is there saves fuel, and makes it easier to get an encounter.

You could save fuel by using a Jool slingshot to contribute some Dv to help circularise your orbit so you do not have to use fuel to reduce your velocity relative to Eeloo, of course this means spending an orbit roughly as far out as Jool, which takes some time, time you can use waiting for Eeloo to get where you need it to be to get an encounter.

This would make the lower fuel launch window nearly a whole Jool orbit earlier than the direct route. There are longer routes that save even more fuel but it is not worth extending the mission by decades to save1 or 2 hundred Dv.