Post 1.0 - Lightest sea level* Eve ascent challenge

[KerikBalm]

Wow, I must not be flying my gravity turns right (a mechjeb advantage here?)

Its also pretty weird that the inversion of the nosecones is reducing drag... but I'll take your word for now.

Can you confirm that nothing breaks if you land on solid ground for the 100m record too?

Its pretty surprising that the 1000 vs sea level mass difference is only 5.5 tons... but that actuall ends up being >16% more massive

[Moonk]

Need some help here.

Yesterday this ship get to the orbit easily. Now she can't even launch from the ground.

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I suspect that there is something wrong with the settings of the game. Even did reinstalling , but it did not help.

Edited August 27, 2015 by Moonk

[Nefrums]

There must have been something wrong with the settings of the game if you managed to get that to orbit using skipper engines, they are almost useless in the thick eve atmosphere.

Are you sure you did not have mainsails instead of skippers on the ship that got to orbit?

[Moonk]

There must have been something wrong with the settings of the game if you managed to get that to orbit using skipper engines, they are almost useless in the thick eve atmosphere.

Are you sure you did not have mainsails instead of skippers on the ship that got to orbit?

Looks like yesterday i made launch hanging chutes few km underground. Couldnt even amagin it will be such difference in thrust.

[KerikBalm]

"Looks like yesterday i made launch hanging chutes few km underground. "

Huh?

Anyway, based on your pictures, it has less than a 1:1 TWR at low elevations on Eve.

You should have KER display the atmospheric TWR stats for Eve.

I can't see how that would get to orbit on Skippers

[Nefrums]

Ther is a huge difference on the thrust generated by most engines at 5km vs 1km attitude on Eve. Skippers is are not recommended. Mainsails work, but they are not as good as aerospikes or mammoths.

[Moonk]

Thank you. Just check it, Twin-boar has the same efficiency as Mainsail, and they both behind Mammoth and Aerospike is the best

[Nefrums]

Yes. since the aerospike buff in 1.0.3 that engine is the best one. That is why almost all landers in this thread rely on it.

[Moonk]

Skipper is far behind... Ahh... i was hoping i found some kind of know-how yesterday, but it is was just launch from high altitude

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Yes. since the aerospike buff in 1.0.3 that engine is the best one. That is why almost all landers in this thread rely on it.

Thanks to you and Foxster , I made 12 stages ship based on aerospikes to lauch my 4 kerbals from Eve ground. But it is so ugly and has more then 250 parts. Trying to find other solution currently.

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"Looks like yesterday i made launch hanging chutes few km underground. "

Huh?

Anyway, based on your pictures, it has less than a 1:1 TWR at low elevations on Eve.

You should have KER display the atmospheric TWR stats for Eve.

I can't see how that would get to orbit on Skippers

Yesterday i was in hurry and didnt add landing gear to ship launching it from chutes. Skippers was realy good, they produce more thrust per engine weight then aerospikes. Too bad they need to be 4-5 km higher underground

[Foxster]

Wow, I must not be flying my gravity turns right (a mechjeb advantage here?)

Yes, MJ does help with the consistency of the lift. For something new I usually do it manually first to get the feel for it, then use MJ after that for fine tuning and consistency between launches.

It's also pretty weird that the inversion of the nosecones is reducing drag... but I'll take your word for now.

I think it's to do with the drag model making the nosecone reduce drag at both the front and rear of the section when it is inverted. To be honest the difference is very small and the craft will work without it.

Can you confirm that nothing breaks if you land on solid ground for the 100m record too?

Yes, it does work fine.

It's pretty surprising that the 1000 vs sea level mass difference is only 5.5 tons... but that actually ends up being >16% more massive

My previous craft for the <1000m entry had about 600m/s spare by orbit from a 950m launch. It worked fine from 60m too but I didn't make an entry for that as I wanted someone else to have a chance to do that. This sea-landing one could be almost the same mass, as the drop tanks at the bottom aren't strictly necessary, they are just supporting the reaction wheels that keep it upright, I could just as well use the first stage tanks for buoyancy, meaning this craft could be the same mass as the previous one plus just one ton for the reaction wheels and PB-NUKs. I thought I'd only bother shaving it down if someone beats it.

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By the way...I have a feeling that I'm homing in on an Eve rocket SSTO. I'm only a few hundred dV short of orbit now.

It will be interesting to see the new engine we are getting in the next release. It just might make this more possible.

[Nefrums]

By the way...I have a feeling that I'm homing in on an Eve rocket SSTO. I'm only a few hundred dV short of orbit now.

It will be interesting to see the new engine we are getting in the next release. It just might make this more possible.

That is cool! are you launching from atop the highest mountain?

[Foxster]

That is cool! are you launching from atop the highest mountain?

Yup. Which might be a problem for the SSTO purists. I need some big legs and landing gear to cope with the slope there and then I'm throwing them away as soon as off the ground. Not sure if that really makes it an SSTO or not. What do you think?

[astrobond]

Hi all

Some pictures of my best (manual) SSTO (pure lol) test, Plane put on Eve with HyperEdit at the coordinates given by Foxster:

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Fly safe with Val

Edited August 27, 2015 by astrobond

[Foxster]

Dang - that was close!

I really think this is do-able.

BTW...the craft I am testing with is almost the same as yours but without the wings.

[astrobond]

Close... but the last dV is really hard to find !!!

More fuel = bad TWR and less dV at AP

Less fuel = better TWR but less dV left at AP

.... grrr

But i'm too sure someone will find a way to do it

Maybe i'll try MechJeb to help me... xD

[Nefrums]

Nice plane. Looks a bit like the plane I used for the eve ssto limbo.

I think I will have to have a go at this Eve SSTO designing.

What are the HE coordinates for the Eve mountain?

Edited August 27, 2015 by Nefrums

[astrobond]

Just for info: Eve's highest point is at (or very close to) HE coordinates Lat -25.000156474942, Lon -158.474595962928.

Thank's Nefrums, yes almost the same as your's !

Just a little more fuel and wings with Angle Of Attack to help climbing

[Nich]

Anyideas how to optimize the AOA? Your AOI looks quite large perhaps more wing and less AOI might get you that 100dV

[Nich]

Also has anyone considered the spark as a first stage booster engine? it has a little better TWR and doesn't seem to be hit as badly as the aerospike by atmoshpere. I am not sure of its Eve performance I am not sure how to get this information. However the additional drag of 10 stacks vs 1 stack may nullify its benefit entirely.

[KerikBalm]

Nice plane. Looks a bit like the plane I used for the eve ssto limbo.

I think I will have to have a go at this Eve SSTO designing.

What are the HE coordinates for the Eve mountain?

http://forum.kerbalspaceprogram.com/threads/132211-Eve-SSTO-Limbo?p=2152534&viewfull=1#post2152534

"Just for info: Eve's highest point is at (or very close to) HE coordinates Lat -25.000156474942, Lon -158.474595962928."

Yup. Which might be a problem for the SSTO purists. I need some big legs and landing gear to cope with the slope there and then I'm throwing them away as soon as off the ground. Not sure if that really makes it an SSTO or not. What do you think?

I think you should make an entry for the SSTO limbo (as should astrobond with his nearly SSTO craft)

In that challenge, I have a category for a reusable craft... if you could attach landing equipment via docking port or something like that... then for each eve landing, one only needs to refuel the craft, and then dock some new landing equipment.

I wonder what astrobond's design would do if it had some LV-N's and LF fuel tanks, a triple mount of them shouldn't hurt the TWR too bad, and it shouldn't be too long before they start pushing their own weight.

[astrobond]

...I wonder what astrobond's design would do if it had some LV-N's and LF fuel tanks, a triple mount of them shouldn't hurt the TWR too bad, and it shouldn't be too long before they start pushing their own weight.

Tested yesterday ^^

But added weight was not balanced by the LV-N's added dV to circularize...

More dV needed at the end than for the published test.

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Anyideas how to optimize the AOA? Your AOI looks quite large perhaps more wing and less AOI might get you that 100dV

Hi Nich

Yes my AOI (and not AOA sorry) is one "shift click rotation tool" angle in VAB, not tried less AOI, could be a good idea

I will also try big new wings...

[astrobond]

Thank's Nich

Less AOI, new wings, a little "diedre" (i don't know if this is the good word in English)

My best try ! Almost done...

[astrobond]

OMG 82m/s of the graal in manual piloting ^^

Now i'm SURE this is doable

(ascent 35°, Prograde at 28km)

[Moonk]

Did 4 kerbals landing and launch

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[Kelderek]

@Moonk: Impressive Eve ship you have there! It never would have occurred to me to do an intentional flip during descent. I would have expected such a flip to yank the ship to pieces. Did you have much trouble getting that to work safely?