Kergarin

August 24, 2016

13 minutes ago, foamyesque said:

I make that a vacuum Eve TWR of 1.3. Hm.

I would have to check how much thrust they generate on 7500m. But it will be verry low above a twr of 1 I think

August 24, 2016

10 hours ago, magnemoe said:

Over 3 year refueling
If you use two large drills it will use 1/5 of the time, also depend on how much ore its on the mountain top.

One tips if you use this on an grand tour is to dock an large ISRU on top docking port then you are not on Eve as it will convert 10 times as much fuel.
For an grand tour I think I would used an smaller tug, Outside of Eve you could use the lander as fuel tank for the tug.

Yes, if I take it to a grand tour I will optimize it. The tug is just a quick build for the video, but it has 6 large drills and a large converter, so it can mine too partially refuel the lander.

8 hours ago, KerikBalm said:

Well, I think ISRU is the only way this worked as a reusable SSTO. He used up a lot of fuel on the way down to prevent overheating. He used fuel to adjust his trajectory to land at the right place...

Nobody had made a SSTO from eve that could actually de-orbit and land before.

This one deorbits and lands, but it needs refueling on the surface. That requires ISRU on the surface.

Now you could seperate the ISRU from the craft, and have some Eve ISRU hopper that could ferry fuel to the mountaintop if the mountaintop has no ISRU... provided there is a suitable source of ore close enough that a rocket powered hopper could bring fuel to the mountaintop... or provided that you have extreme patience and can drive it up there with electric wheels.

Otherwise, you send down lots of disposable fuel tanks to the surface to refuel the SSTO

There are a lot of ways to speed up mining, in this model I was just after an all in one solutions that also looks and flies nice.

2 hours ago, foamyesque said:

EDIT:

@Kergarin: What were your fully-fueled vac deltaV/TWR numbers? I'd like to know roughly what I need to shoot for while I work on this sucker:

Since I'm playing stock, I do not have a display for that, but profossi on reddit calculated these numbers based on the video:

Property	Value	Unit
Dry mass	279.62	t
Propellant when fully loaded	1168	t
Propellant expended	1165.3	t
Propellant after reaching LEO	2.71	t
"Mammoth" engine ISP (vac)	315	s
Eff. exhaust velocity (vac)	3089.2	m/s
Vac. ∆V when fully loaded	5079.4	m/s
Vac. ∆V expended	5049.6	m/s
Vac. ∆V after reaching LEO	29.8	m/s
"Extra" propellant at launch	13.9	t
Propellant margin	1.2	%

That's around 1448tons on 8 mammoth - to calculate twr.

7 minutes ago, Brainlord Mesomorph said:

You must have been up late, dude.

Did you know that ship is named "MONOLTIH 1"

You right with both, have realized it while uploading and have mentioned in the video description... But this was to much work to record again. :huh:

August 24, 2016

8 minutes ago, KerikBalm said:

Wow... 3 year refeuling time.... yea... if I were to use something like this in career, I'd havae a surface base refeuler that just claws to it to refeul it.

Swapping for a full sizedd ISRU gets 5x the fuel per unit of ore drilled -> down to less than a year. I forget how much faster the large drills mine, but with a surface station, you could slap on as many as you want, and use gigantor solar (I think solar works ok at that altitude on eve... it doesn't work so well at sea level).

That margin was razor thin though... I don't use mechjeb, and I wouldn't be comfortable in the margins for getting it to space. I think I'd almost prefer the sub-orbital rendevous concept.

Can you get ot the chutes to repack them on the surface? or must you EVA in space to repack them? If you can repack the chutes while on the surface, then that could be turned into a biome hopper (assuming you find ore in each biome), as long as it returns to the highest peak - but a faster ISRU solution would be desirable otherwise that could take decades

For sure there are many ways to make this more efficient.

My goal was just to make it deorbit and orbit autonomusly at all costs.

The margins are not as bad as they seem. I'm flying manually on keyboard. You just need to start the gravity turn at the right time.

The chutes have to be packed in space unless you add ladders. But you can also use it as biome hopper by landing without chutes.

August 24, 2016

6 hours ago, Justicier said:

As much as I love making SSTO spaceplanes... this is one project I could never bring myself to take on. So many parts... so much CPU load... so little framerate. Huge props to anybody who has successfully done an Eve SSTO, Spaceplane or otherwise.

It was more than a hundred hours of really hard work just to build this one working lander, plus several hundred hours of experience in building SSTOs.

But the result is worth the pain I think

59 minutes ago, Brainlord Mesomorph said:

ooookaaay.

As I have already said, you, sir, are a steely eyed missile-man.

now I'm going to need some numbers:

1. what does that thing COST? (16 PBNuks? that alone is half my budget) I'll assume you're not in career,

2. total fuel capacity? wet mass? dry mass?

3. are you burning all the fuel on landing?

4. is that the only way to keep it from burning up? could it be landed on chutes alone fully fueled?

5. How long did that refuel take? (is that 3 and half YEARS?)

wow,

that is indeed a wow.

I hear that in Darth Vader's voice

Edit: And I can save you 350 parts right now: Why does the tug have engines? With all the engines on the lander, the tug just needs to be what I call an Autonomous Drop Tank. Just enough FUEL (and O2) for the lander to get itself back and forth from Gilly to LEO. Once you do that the rest of the solar system is yours.

I'm at work right now and will have to answer this later. What I can say:

3. Yes almost all

4. Yes. You would need to add (disposable?) heatshields.

No. Drop rate is around 35m/s on chutes only.

5. Ahm... Yes... But you can change this to the large drills to speed it up.

34 minutes ago, magnemoe said:

Problem is that you have to pull that with an standard docking port.
On the other hand I would probably sent that ship from Minmus to Eve with its own engines, refuel it on Gilly, having an LV-N based tanker who also refiled on Gilly and refiled lander in low Eve orbit.
It looks like many parts is used to make the tug wider something who is not needed if it don't pull the lander.

The tug was just a quick build to have something cool looking for the video, since it is mainly about the SSTO. It will change if I really use it for a grand tour.

August 24, 2016

42 minutes ago, foamyesque said:

Pretty sure you can't see Kerbals from the outside in stock. (1:50 in the vid)

I don't know since when, but this ist stock in 1.1.3

There is a little round button left to the Kerbals "portraits"

August 24, 2016

5 hours ago, magnemoe said:

Impressive.

Thanks

4 hours ago, foamyesque said:

That is really impressive. Looks like you had some mods going? And what's the story with the hatch in the Mammoth?

Thanks it's absolutely stock. @magnemoe is right, it's a mk1 lander can, clipped into the mammoth. I think this kind of clipping is ok, since it doesn't give me any other advantage than a better looking. The thing would work with long ladders too

4 hours ago, Justicier said:

As much as I love making SSTO spaceplanes... this is one project I could never bring myself to take on. So many parts... so much CPU load... so little framerate. Huge props to anybody who has successfully done an Eve SSTO, Spaceplane or otherwise.

The lander itself has 123parts, that's actually good to handle. The problem is the interplanetary ship, which adds around 350 parts. That means 2-5 fps :huh:

3 hours ago, JadeOfMaar said:

O_O! It's....it's the king of landers! Such precision and efficiency!

Thanks to be honest... The landing didn't succeed in the first try... it might have been two or three or a million attempts

1 hour ago, KerikBalm said:

Its been done....

How many drills are you using? just 2 small ones? could you make it work with 1 large one, so that it can land in more places (no minimum 2.5% ore restriction)?

What is its power source? I assume you're using the small convertor... plus small drills, means very power intensive mining... doesn't seem like fuel cells would work for a net gain...

Yes it has just 2 small ones. They are powered by 16 NUK generators inside the small bays.

This lander has a payload of ~10tons - if flown correctly. So you can also put large drills on it. The only reason why I'm using the small ones, is to make look better vor the video

August 24, 2016

Turn up volume

August 23, 2016

10 hours ago, Brainlord Mesomorph said:

Usually in this game I feel like the Director of NASA, deciding what flights I can afford and which mission to scrub. Other times I feel like the CEO of an aerospace company trying to design vehicles to accomplish missions.

Lately (in this thread) feel like the CEO of an aerospace company whose competition has succeeded where we have failed. I have tidbits of press releases, corporate espionage, some footage of a successful test of a model,and a mass number (w/ a typo).

And then we're in the VAB trying to guess what arrangement of parts adds up to that. ("we", me and the other Kerbals)

The most time I feel like a mad rocket scientist

Video will hopefully come tomorrow, it's all recorded, only needs to be cut.

August 23, 2016

Landing: works

Isru: works

SSTO: works

All systems go the video should be there tomorrow.

1.448 tons with ~10 tons payload.

I was even able to give it an Mk3 cockpit, but that doesn't look verry well, so I switched back some other pods :huh:

August 22, 2016

15 hours ago, JadeOfMaar said:

A powerful motivation started coming over me a few days ago to try to create a flag in honor of @Kergarin and his Ultimate Challenge SSTO. I've come up with 8 ideas so far but none run as deep as these two finalist ideas. They are perfectly sized to download and plug into the game.

The first is most suited for branding and hence contains his name. With just three reference objects, it tells the story "With this same Rapier, I have slain Eve, and I have slain Jool."

The second is better for a badge or banner and clearly sows that his ship, the Excalibur, has been literally everywhere. There is significance to the display of moons behind the chevrons-- those moons and their kooky orbits.

~~The plane below is not intended to fly.~~

Wow! What an honour! :0.0:

I like the second one and will definitely take this with me on my next grand tour.

August 21, 2016

30 minutes ago, KerikBalm said:

Well, I had a go at Eve SSTO. I tried a crossfeeding design with a mammoth and 4 aerospikes. Aerospikes have better Isp throughout pretty much the whole ascent, but their TWR is inferior to the mammoth.

But, especially since its a SSTO, the mammoth has way more thrust than needed in later parts of the flight. So I have 4 aerospikes and a mammoth, I throttle back the mammoth with the slider/shut it down once I'm going mostly horizontal, and just let the aerospikes push the rest of the way with their 8% better Isp. I barely made orbit from the highest point on eve... so I guess its no better than the mammoth only designs

Has anyone landed one of these yet?

The mix of aerospikes and mammoth were in my test worse or equal to mammoth only designs.

Yes I have just landed my isru ssto. Just working on some beauty fixes and hope to have a video tomorrow.

August 21, 2016

It's now a 10 ton payload eve ssto :confused:

Reached orbit with isru mk1 cockpit and 8tons of spare fuel.

August 21, 2016

2 minutes ago, DualDesertEagle said:

Just a little something I keep noticing over and over again: What is it with this "turn right to head east on take-off" thing? I keep wondering why all spacecraft deployed on the launch pad by default are oriented in a way that pitching down would make them head north instead of east. So what makes such a counter-intuitive thing better than launching them belly-to-the-east so u can simply pitch down to get the correct heading?

I think it's to match the default camera perspective. Now someone could ask why the camera is oriented this way.

2 minutes ago, Brainlord Mesomorph said:

indeed.

I'd love to see a pic of what you have so I could think about that mothership

As soon as it's works like expected, there will be a video

August 21, 2016

11 hours ago, Brainlord Mesomorph said:

more than certainly.

I have been waiting for the appropriate time to use the following compliment on this forum (I believe it should be our highest commendation):

You, sir, are a steely eyed missile-man.

Thanks, what an honour

Maybe this is due to a lack of sleep, but what if I use an SSTO to move an asteroid to low eve orbit, and use this to refuel the lander using its ISRU?? instead of using a mothership to move the lander around. :confused:

August 20, 2016

On 14.8.2016 at 0:02 AM, Brainlord Mesomorph said:

toying w/ eve lander designs, and it occurs to me:

"If you make an Eve SSTO rocket, do you win this game?"

its supposed to take 8km/s of dV, and if your rocket can do that (and refuel) doesn't that mean it can ANYTHING else in this game?

Such a rocketship would easily take it self to LKO with plenty of fuel to land on Minmus and refuel and then it could go and land ANYWHERE. Do anything, without any help, without a fuel tender, it wouldn't even need gantries, b/c it would have to land on Eve, it would the ultimate KSP rocket!! Am i right?

this begs the question: can it be done with stock parts??

Well I'm just answering this question. Nothing more, nothing less.

Most of this thread is theory and assumptions, and im posting what I know from SEVERAL HUNDRED launches on Eve, to help others and make clear which assumptions are right and which are wrong.

I have started working on an Eve SSTO long before, but this thread really motivated me a lot, to focus on this and show what's possible.

But this has nothing to do with fun anymore, it's hard work and took several weeks of my life to get this far.

If you would like to ~~steal~~ build a Hercules named sistership of my MONOLITH once it's released, that would be ok to me. But it would be nice, if you then refer to its original

Apart from this, the thing is working. I'm just trying to give the Kerbals a more comfy place than sitting between the engines I have a version with a prograde facing Mk1 cockpit at the lower top of the rocket (like on a container ship), this gives the pilot a really impressive view, but adds to much weight compared to the lander can... :huh: while it's great to outbalance the ISRU equipment.

August 20, 2016

Which mission plan?

Why do I get the feeling I'm developing something for you?

August 20, 2016

I have just build an SSTO which brings 2 Kerbals to Orbit. ISRU seems so near.

August 20, 2016

48 minutes ago, Brainlord Mesomorph said:

The MK1 inline has a higher max temp. Could it be mounted radially on the bottom (Millenium Falcon style?)

you could offset the weight and drag w/ a fuel tank on the other side?

Also how about Disposable Replaceable Heat Shields?

with that shielded docking port on the nose, you could mount an Inflatable heat shield on a docking port and dock them in orbit, enter Eve atmosphere, and then toss the thing right before parachute deployment.

The sistership could carry 3 or 4 spares.

Thanks for the tip. But radial mounting will require additional parts like nose and tail cones, which will result in extra weight and drag. There is really no margin without massive upscaling.

I will try to make this thing 100% reusable, so disposable parts would be my last way out.

August 20, 2016

1 hour ago, GoSlash27 said:

Makes sense for a high altitude SSTO.

Best,
-Slashy

I think high altitude is the only altitude that works. Even from 1.000m less it seems impossible.

Every letter and number of the model name C9H8 stands for a new type, model and version that I have tested. And that's not a straight line, there a dozens parallel to that. Nothing else worked.

1 hour ago, Brainlord Mesomorph said:

That's what I was thinking, but you guys seemed so sure of the opposite.

The tough part is going to be reliably landing that thing upright.

good work!

Thanks

I think my upscaled version can land, and its so wide that it won't flip. But it's still 120m/s short on ascend...

47 minutes ago, magnemoe said:

Congratulation well done.
Payload here is an 100 kg probe core, is it an shielded docking port in front? That is 100 kg more, as I can see no power or reaction wheels or fins.
An Mk1 pod will be 0.84 ton and should be doable.

ISRU is another issue, the small isru have so low efficiency it will use many months filling the huge rocket. My Tylo ssto use a week and only hold around an orange tank of fuel.
It also had two of the large drills. bringing the total weight up to 1.25*2+125 its also award to place without generate lots of drag, As I used the SSTO on Laythe too I put drills and isru into MK2 cargo bays with MK2 probes as bottom and aerospike as engine, this too has plenty with drag,

Thanks

The shielded docking port is the only part that I found to be heat resistant enough. If I go up any slower, I don't reach orbit, even not with the reduced weight or drag of the other nosecones that I have tested.

The only reaction wheels are the ones inside the probe core. That's just enoug to keep it straight before reaching orbit. The rest is done by engine gimbal.

The problem by using the mk1 Pod isn't weight, it's heat again. I just can't get fast enough, without exploding the pod. (if it's top mounted) Also a really usable top mounted pod would need ladders. And ladders are enough to change the the CoM so badly, that the rocket will flip.

I have tried a bottom mounted lander can, but you can't get back inside it, because it's not possible to walk between the engines of the mammoth. (collision box does not match the real model) :huh:

An ISRU refuel will take month, if not years.

But there is a much bigger problem: there is no ore at my launch site

August 20, 2016

Finally... here is the video

August 20, 2016

So here it is.

It's the total oposite of what i was thinking about when i started working on an Eve SSTO... :confused:

No wings, no drag. Just get out of the soup as fast as possible.

Im working on an upscaled manned version with ISRU. But that only reaches 3.080m/s at 90km AP by now. Seems possilbe!

August 19, 2016

Did it!!!

(at least unmanned SSTO from EVE, landing is another part :confused: )

The video and details will follow soon!

August 19, 2016

3 hours ago, magnemoe said:

I referred to the videos as I have not done it myself, I never talked about staying slow, just an takeoff and low attitude TWR who is less than that would work on an rocket.

Ok, then I got you wrong, sorry. I thought you were talking about something like "just a few aerospikes"

3 hours ago, magnemoe said:

It might even be an idea to increase climb rate as in becoming an rocket once your TWR start to become reasonable for an rocket to reduce drag an heating then pull nose down for the gravity turn.

That's exactly how I did it in my first attempts.

But it seems more efficient, to climb in a straight line until you go into a gravity turn.

At the moment when twr is high enough to increase climb rate, the atmosphere is already so thin, that you can fly more efficient straigt throug it.

August 19, 2016

27 minutes ago, magnemoe said:

No not tried it, watched the Eve SSTO video and the one with an full reusable Eve mission with tug to circulate, both used an winged rocket.
I'm a rocket guy myself and not an good pilot, but it looks to me that you would not get an standard rocket of Eve as ssto as the twr get to low.

I think the question is: how do you define low twr and slow ascend? Until now, I was thinking you are talking about something, that's much slower than the planes in those two videos.

My best eve planes have a takeoff speed of around 150m/s and i'm trying to keep it at 200m/s on full throttle at around 45degree angle until I'm out of the soup.

Is this what you mean by slow, or are you talking about even less?

August 19, 2016

1 minute ago, magnemoe said:

The benefit of an winged accent stage is that you can manage with lower TWR as the wings takes much of the gravity loss, the penalty is drag, the drag really come back and bite you as you move faster.
Look at designs for real world winged spaceplanes.
On kerbin the rules are a bit different as we can use the very efficient jet engines.

Have you tried it?

I did several times.

It just does not work on eve.

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