is an Eve SSTO rocket possible?

[Kergarin]

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. 

[foamyesque]

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

[Kergarin]

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

[astrobond]

20 hours ago, Kergarin said:

 

Turn up volume 

@Kergarin Just...WOW !!! Really impressive and efficient ship  Congratulations !!! you just win the 1.1.3 game  

[CallisTrOn Entertainment]

OK, you won Eve. Now we want to see a nice video of the grand tour.

 

And if you still won't get bored of the game after this, then you win this game :-)

[foamyesque]

Well, progress. I can land it on Eve. It blew apart coming out of timewarp during the ISRU, though . :v

[Kergarin]

20 hours ago, astrobond said:

@Kergarin Just...WOW !!! Really impressive and efficient ship  Congratulations !!! you just win the 1.1.3 game  

Thanks!  As I already wrote on youtube, your Eve SSTO video gave me the power to keep trying. 

My first designs were winged too, but it seems a rocket is the way to go in 1.1.3

11 hours ago, CallisTrOn Entertainment said:

OK, you won Eve. Now we want to see a nice video of the grand tour.

 

And if you still won't get bored of the game after this, then you win this game :-)

This would take some time, my last grand tour took 3 month to develop and execute 

See: https://youtu.be/FXAzQk01vuw

 

8 hours ago, foamyesque said:

Well, progress. I can land it on Eve. It blew apart coming out of timewarp during the ISRU, though . :v

Maybe it just gets to heavy with the produced fuel,  and then breaks when you return to normal speed/physics?

 

 

 

Something I have realized now that I had more sleep than the last days: 

All my plane attempts were done from 6.800m and also this rocket was developed on this height.

When @Stratzenblitz75 told me there is also a 7.500m launchsite, I already gave up plane designs and was happy that my actual rocket design worked from there.

It reached orbit with ~10tons of fuel left, and I did not try to scale it down again.

Maybe it can be downscaled to the half size or less. also a really small single seater should be possible.

Edited August 25, 2016 by Kergarin

[foamyesque]

26 minutes ago, Kergarin said:

Maybe it just gets to heavy with the produced fuel,  and then breaks when you return to normal speed/physics?

 

Possible. I'm not completely sure, though, since it was only about half-loaded and it's fine on Kerbin with a full fuel load. It'll take some poking.

[Brainlord Mesomorph]

So, now I'm trying one of these.

I'm working with a 3/4 scale version: 1000 tons 6 mammoths. (same TWR and dV, less payload) my idea was to remove the ISRU, add a detactable/replaceable inflatable heat shield and parachute it down fully fueled. That may not be possible.

Kergarin is getting several advantages by burning all the fuel on the way down. The inflatable heat shield is not big enough even for my smaller ship, by using engines to slow down he's not generating nearly as much heat. He has more control than I do, and he's only landing a 270 ton ship, a QUARTER of the smaller one I'm (not) landing.

So I'm saying ISRU may be the ONLY way to this.

(all the more congrats)

Edited August 25, 2016 by Brainlord Mesomorph

[Kergarin]

23 minutes ago, Brainlord Mesomorph said:

So, now I'm trying one of these.

I'm working with a 3/4 scale version: 1000 tons 6 mammoths. (same TWR and dV, less payload) my idea was to remove the ISRU, add a detactable/replaceable inflatable heat shield and parachute it down fully fueled. That may not be possible.

Kergarin is getting several advantages by burning all the fuel on the way down. The inflatable heat shield is not big enough even for my smaller ship, by using engines to slow down he's not generating nearly as much heat. He has more control than I do, and he's only landing a 270 ton ship, a QUARTER of the smaller one I'm (not) landing.

So I'm saying ISRU may be the ONLY way to this.

(all the more congrats)

I think you will need a lot of inflatable heatshields and an insane amount of parachutes.

If you either land on that heatshields or mount them on top of your lander, they could assist the parachutes down to landing. But you would have to check if this works, just an idea.

[foamyesque]

Actually, just to be sure here, Kergain: Your descent is done after refuelling at the orbiting mother ship, right?

[Brainlord Mesomorph]

6 minutes ago, Kergarin said:

I think you will need a lot of inflatable heatshields and an insane amount of parachutes.

If you either land on that heatshields or mount them on top of your lander, they could assist the parachutes down to landing. But you would have to check if this works, just an idea.

so far even insane parachutes only slow it to 18 m/s on Kerbin, but i'm still workig on the >1 heat shields

 

4 minutes ago, foamyesque said:

Actually, just to be sure here, Kergain: Your descent is done after refuelling at the orbiting mother ship, right?

IFAIK that's a "show" mothership and he hyperedited that to Eve orbit. (for the video) but hypothetically, yes.

Edited August 25, 2016 by Brainlord Mesomorph

[foamyesque]

2 minutes ago, Brainlord Mesomorph said:

IFAIK that's a "show" mothership and he hyperedited that to Eve orbit. (for the video) but hypothetically, yes.

I know it's a show mothership, but I'm pretty sure he needs its fuel to perform his second descent.

[Kergarin]

29 minutes ago, foamyesque said:

Actually, just to be sure here, Kergain: Your descent is done after refuelling at the orbiting mother ship, right?

The lander and the mothership do both refuel at Gilly. The mothership then takes the fully loaded lander to low eve orbit. 

 

But since it's nothing special to move a ship from Gilly to eve, I only concentrated on the lander for now, the mothership might need resizing if it should bring the lander also to moho and so on for a grand tour.

If you do a late suicide burn, the ship won't need all its fuel to descend. Maybe it can get from Gilly to low eve orbit by a lot of aerobraking with enough fuel to land safe. But since can't leave eve orbit alone after this, it will always need a mothership, so I haven't tested this.

25 minutes ago, Brainlord Mesomorph said:

so far even insane parachutes only slow it to 18 m/s on Kerbin, but i'm still workig on the >1 heat shields

 

IFAIK that's a "show" mothership and he hyperedited that to Eve orbit. (for the video) but hypothetically, yes.

What speed is that on eve? It will vary.

Yes, I just didn't want to wait the burntime it would take on my computer to get there on nervs with a 450part ship at almost no framerate  but the mothership should be able to do this. The worst possible thing would be, that I need to add more fuel tanks. The video is just about the lander and the mothership should show that one is needed to pull it away from eve.

22 minutes ago, foamyesque said:

I know it's a show mothership, but I'm pretty sure he needs its fuel to perform his second descent.

For a second descend they both need to refuel at Gilly again. A mothership that can take the lander plus more than a thousand tons spare fuel for a second descend to eve would be... Gigantic

Edited August 25, 2016 by Kergarin

[Kergarin]

31 minutes ago, foamyesque said:

I know it's a show mothership, but I'm pretty sure he needs its fuel to perform his second descent.

Or you could use a tanker instead that harvests alone at Gilly and then refuels the lander in orbit. So it doesn't need to be moved around.

[GoSlash27]

On 8/24/2016 at 5:32 PM, foamyesque said:

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

foamyesque,
 Not that unusual. High initial t/w is good for minimal DV to orbit, but if you want max payload fraction or minimal cost per tonne, you have to set it lower. Most of my launchers operate in this range.
 Plus, he's battling tremendous heat.

Best,
-Slashy

[foamyesque]

1 hour ago, GoSlash27 said:

foamyesque,
 Not that unusual. High initial t/w is good for minimal DV to orbit, but if you want max payload fraction or minimal cost per tonne, you have to set it lower. Most of my launchers operate in this range.
 Plus, he's battling tremendous heat.

Best,
-Slashy

Didn't say it was unusual. It's actually massively higher than my TWR, because I'm working on a plane layout -- it has an Eve vac TWR of 0.8. It was more a point of interest than anything else

 

Edited August 26, 2016 by foamyesque

[Brainlord Mesomorph]

Where is that high flat spot he landed on? (specifically, please)

[foamyesque]

15 minutes ago, Brainlord Mesomorph said:

Where is that high flat spot he landed on? (specifically, please)

 

I think it's here: http://www.kerbalmaps.com/?body=eve&style=color&loc=-24.9946,-158.4744,Highest+Elevation
7541+m
-24.9946+:+-158.4744

[GoSlash27]

8 hours ago, foamyesque said:

Didn't say it was unusual. It's actually massively higher than my TWR, because I'm working on a plane layout -- it has an Eve vac TWR of 0.8. It was more a point of interest than anything else

 

Eve sea level??

Ambitious!

-Slashy

[KerikBalm]

Where does he say anything about sea level? Sure the pic is at 1200m, but thats still quite different from sea level, and it may have been just a test without landing it at the mountain that basically must be used for this to work

[GoSlash27]

38 minutes ago, KerikBalm said:

Where does he say anything about sea level? Sure the pic is at 1200m, but thats still quite different from sea level, and it may have been just a test without landing it at the mountain that basically must be used for this to work

Well... he *is* refueling down there for some reason  It's his project, so he'd be the one to ask.

FWIW I agree with you; I don't think sea level SSTO can be done, but I'll be thrilled if I'm proven wrong.

Best,
-Slashy

[KerikBalm]

but you could refuel at sea level, then relocate to the mountain, then refuel again...

"It's his project, so he'd be the one to ask. " - but you're the only one who said anything about sea level, unless he's edited it out since you read it/

[Kergarin]

8 hours ago, Brainlord Mesomorph said:

Where is that high flat spot he landed on? (specifically, please)

I've got these coordinates from Stratzenblitz75 at reddit: -25,-158.45

They work perfectly for hyperedit.

 

5 minutes ago, GoSlash27 said:

 

FWIW I agree with you; I don't think sea level SSTO can be done, but I'll be thrilled if I'm proven wrong

Already the difference between 7500m and 6800m is massive... Sea level seems impossible without staging

[Sharpy]

25 minutes ago, GoSlash27 said:

FWIW I agree with you; I don't think sea level SSTO can be done, but I'll be thrilled if I'm proven wrong.

Best,
-Slashy

 

18 minutes ago, Kergarin said:

Already the difference between 7500m and 6800m is massive... Sea level seems impossible without staging

Or wheels.