Eve Return with 2 Kerbal lander can in version 0.23 with a bunch of (non OP) mods

[A35K]

So I still have this 0.23 save which I often use. The main reason why I keep this is because it has this planet mod (Krag's Planet Factory) which has a bunch of cool planets which I never got around to going to, but the mod is not compatible with later versions. However this ended up being the save where I do most of my 'proper' missions in sandbox mode, mostly so that I won't get interrupted with updates. So I decided to do an Eve return mission, since I have never done it. Here we go:

The hardest part by far was designing the lander. Surprisingly, achieving the required Dv was not hard at all (although looking back, it could have been much more efficient. This design could achieve orbit from around 2000m from sea level on Eve), but making it able to sit on the ground on Eve without disintegrating was very challenging. Also finding the right amount of parachutes so that it would slow it down enough, and at the same time not break it apart. The final contraption weighed in at around 900 tonnes and 800 parts, including the largest fuel tank I ever made (using procedural tanks mod). Other mods I used were B9 for a bunch of lights and a few reaction wheels (nothing important at all), and KW rocketry for a few fuel tanks and 1 engine. MechJeb was necessary to control this 800 part monstrosity efficiently, due to lag.

Here is the first image:
This was before some minor tweaks such as the changing of the landing gear, as this one resulted in the whole ship vibrating after landing and exploding (as I discovered after a bunch of hyperedit tests on Eve), and adding drogue chutes. Anyway, as you can see, each stage has a TWR of exactly 1 on Eve, (1.7 on Kerbin), except the last stage, as this was before I added two of the tiny radial Rockomax engines (28-R?). Here's a breakdown of each stage (bottom to top):
1: Powered by 10 Mainsails, this is the stage that lifts the whole things up to around 7000m. The huge fuel tank holds about 40,000 units of liquid fuel. All those huge conical fuel tanks are made with the procedural tanks mod. I realised after building it that it sort of resembled a short and fat N1:D.
2: This stage is powered by 16 aerospikes, lifts it out of the thick atmosphere.
3: This is the crucial stage, powered by 8 aerospikes, gets it up nearly out of the atmosphere, and gets it up to about half orbital velocity.
4: This stage completes the orbital insertion, and is powered by an engine in the KW pack, called the Atlas Low Profile engine, which is designed for landers and is very flat. It has 120kN thrust and ISP of around 390, so nothing special.

Launching this thing to space intact was quite challenging, but my 1000 tonne lifter did the job (after a few tries due to unplanned disintegration). This thing had more than 1200 parts, so the lag made mechjeb autopilot necessary:
The first stage of the lifter is powered only by those 4 SRBs, which are built using the procedural tanks mod again, each produces a thrust of around 25,000kN! (Ok, this part might be somewhat cheaty... the mod lets you scale SRBs to whatever size, readjusting the thrust.) The fuel tanks you see underneath are 5m KW tanks, and each of those engine clusters produces 11,000kN of thrust. The whole thing weighs about 3000-4000 tonnes on launch. As you can see I added 2 radial Skipper engines on the lander to aid with the landing.


Dropping the massive SRBs (You might be wondering why there are no flames coming out of the engine. I think it's a glitch with KW on my save as most of their large engines do that, but they work normally.):


Separation of next stage:


And the next stage:


And the stage after that


Circularising:


To get this lander to Eve, an equally large transfer stage had to be sent up using the same lifter, and docking these two behemoths was quite challenging, requiring over 7000 units of monopropellant from the 'tug' (unfortunately forgot to take pictures of the launch and docking, but it was very tedious, at least they used a 3.75m docking port which was part of KW), which also weighed about 1000 tonnes, and was built using 5 KW 3.75m tanks, and powered by 16 LV-Ns and 1 KW rocketry 3.75m engine that has the same thrust as a Mainsail with similar ISP (used as a boost during the Kerbin escape burn). By the way, this mission also includes a rover and a bunch of scout probes to find the best landing site, which were sent to Eve using a much smaller ship, which you'll see later as I forgot to take pictures of it departing Kerbin. But it is a KW 2m tank powered by 6 LV-Ns basically (this is used to return the capsule back to Kerbin). Anyway, quite a lot of real life time passed between this picture and the next, as I had taken a break from KSP, by which time I had installed the Interstellar mod (this might have caused slight unexpected problems, as you will see later), which I used to build a new Plasma Powered SSTO to bring the crew to the ship in LKO (which required 14GW of power beamed to it using reactors in orbit). The crew consists of Lodory and Edvis Kerman, veterans of my Dres mission, and first Kerbals to Dres (and anywhere beyond Duna). There is no way I would have launched the crew on that lifter:D:


In atmosphere it uses Monopropellant, giving it an ISP of around 2700s (comparable to jet engines) and a thrust of around 475kN.


In space, it uses Vacuum Plasma mode, which means it uses no fuel whatsoever, albeit with a penalty in thrust, which decreases to around 200kN (here approaching the 'KSS Mercury', as I called the lander):


After a game crash, finally reached the KSS Mercury, interplanetary tug already docked:


Transfer burn:


The transfer stage had around 2500m/s of Dv, more than enough to get to Eve.


Plane change in Solar orbit:


Thanks to a low energy transfer, only minimal aerobraking was required to capture, ensuring the ship didn't disintegrate... Although 5 aerobraking passes were required to get to low orbit. Mechjeb came in handy here as it tells you your trajectory after aerobraking (The orientation of the lander was always changed using the autopilot due to lag and lack of RCS, with only few reaction wheels):


First pass (the node Dv is what mechjeb says you get from aerobraking):


Orbit after aerobraking and predicted orbit after next pass:


Approaching Eve again:


Final circular orbit at 120km after a few more passes:


Here is the vessel carrying the 8 scout probes and rover, arriving at Eve:


Being a much smaller and structurally stronger ship, the aerobrake to low orbit was done in one pass, resulting in the ship turning into a meteor:cool:: By the way, remember how I said the Interstellar mod could cause problems, even if the ship doesn't have any part from it? Well, it adds a waste heat mechanic, which means that the closer the solar panels are to the sun, the more heat they produce, which has to be dissipated with radiators, which the ship doesn't have, or else everything shuts down. So I had to retract all panels except one.


Final orbit of the ship (same as the Mercury, to facilitate docking afterwards):


The first probe was dropped, which caused a strange bug where the mothership would not stop rotating, probably something to do with the decoupler being attached to a 'massless' part (the cubic octagonal strut). I managed to stop it by decoupling the opposite probe:


Each probe has mechjeb as it tells you precisely where you will be landing on atmospheric planets. Each probe consists of a flat octagonal probe core, the OSCAR-B fuel tank, and 2 radial LV-1s and a small parachute. Fortunately, I found the perfect location with the first probe, as it was above 2000m ASL and very flat. I decided to drop the other 7 probes anyway, not like they were going to be useful for anything:


De-orbiting the rover:


Another fireball:


Dropping the fuel tank and engine:


After chute deployment:


Touchdown in the green sunrise:


De-orbiting the Mercury. The tug is separated and crashes ahead of the landing site:


A vary large fireball. One good thing about the shape of the Mercury is that it is very bottom-heavy, which makes it very stable during re-entry. No turning back now, but the pilots don't seem bothered by the fact they could never go home if even the slightest thing goes wrong... (This is not using autopilot, the landing guidance window just tells me how far from the target, which is the probe, I will land).


After a whole bunch of chutes deployed. However a lot of them have been cut, since I landed at a higher altitude than expected, so it would have been going too fast and it would have broken apart. As you can see, the landing gear is now made of structural beams, with loads of B9 wheels at the bottom. The whole gear decouples for takeoff, as it weighs over 4 tonnes.


Touchdown! As you can see, the 2 Skipper boosters are dry, and I used a little more fuel than necessary, as less parachutes were used. But I landed at a higher altitude, so that should compensate for it, since by design it should reach orbit from 2000m.


Jettisoning the parachutes in true Kerbal style using SRBs:cool::


Lodory steps out, and becomes the first Kerbal to have been to the surface of Eve:


The mighty lander with Lodory and Edvis in front (I believe I measured the whole rocket to be about 25m tall):


Mandatory flag planting...


And Lodory runs excitedly towards the rover, to begin the exploration of the area:


Part 2, the exploration and return coming next!

Edited November 30, 2015 by A35K

[A35K]

OK, so here's part 2:

Ready for the first rover trip:


Approaching a lake:


The Kerbals go for a swim, becoming the first to do so on another planet:


Leaving the ocean and lakes after planting a flag and after a nice day at the beach:cool::


After a few hours, they went on a trip to a nearby peak. Nice view:


Speeding down a hill, returning to the Mercury for their first night on Eve (notice the speedometer? I actually got up to 55m/s down some hills, at which point the rover was bouncing around uncontrollably, but thankfully it had reaction wheels with SAS which kept it stable):


Enjoying the beautiful Eve sunset, bright green:


If you look just below the HUD brake icon, you will see a small dot which caught my eye, so I brought up the map to check what planet it was (I have distant object enhancement installed):

Map. Nothing there (look perpendicular to Eve's orbit away from the sun, as that is the direction the object should be at)...


Turns out I had to zoom way out, as it was Serious that I saw, a dwarf star orbiting very far from Kerbol, which is part of the planet factory mod. The fact that it looks so bright even from Eve definitely confirms it is a star. Probe you see with that huge elliptical orbit was not meant to go to the star, it was actually launched before I installed the mod, and passed just above the surface of the Sun, and then ended up in the current orbit after getting a Jool assist (by pure chance).


The second day the kerbals went on another nearby peak, this time to the south, and then back towards the ocean on the other side of the thin strip of land we arrived on.
Here's kerbal walking back to the rover after falling off at 40m/s...


By the way, this is the area where we landed, the lander is in the middle of the thin strip of land, the flag on the other side is the one that was planted near the ocean, and the station and rover icons are actually on the other side of the planet, so ignore them...


Approaching the coast on the other side (where the huge red cross is in the picture above):


After going for another swim, they begin to return to the Mercury, however we suffered an accident on the rover while flying down a hill at 50m/s, which broke a few wheels and the rover's only headlight:


Fortunately wheels can be fixed by Kerbals, and they were back on the way. Here they approach the Mercury, clearly visible from more than 1 km away (even though here it's only 300m...):


The next morning, preparations for takeoff are made, after a successful 2 day mission and 4 rover trips each about 100km. The next launch window to Kerbin isn't until 250 days, but the return stage in orbit has more than 7000m/s of delta-v, so we can take a shortcut and leave now, avoiding a 250 day wait:). Ladders retracted, empty Skipper boosters dropped (stats for each stage are displayed. The 0.97 TWR on the first stage is due to the landing gear which hasn't been decoupled yet, (obviously...):


And liftoff! For max efficiency, the ascent is controlled by MechJeb (even though I had to set the parameters myself for which altitude to turn at, etc. During testing I found 23km to be optimal). I selected the autostage option with a delay of 0, so that the second a stage is dry, the next one ignites, to reduce gravity losses, which is especially important since most stages have a TWR of exactly 1. Here the landing gear is decoupled:


Ascending:


First stage runs out at about 7500m, with an atmospheric pressure of 1.7 atm, as you can see. When the aerospikes ignited, they destroyed the bottom tank, leaving a quite cool formation of aerodynamic fins:cool::


Second stage burning:


Ignition of third stage. No explosion this time;.;.


Picking up speed (this is the stage with the most D-v):


Commencing gravity turn (Lodory and Edvis seem concerned...):


Blasting out of the atmosphere:


Separation of third stage and ignition of 4th and final stage (screenshot just at the right time!):


In order to increase available delta-v, as soon as the TWR reaches 1.3, the radial Rockomax engines are switched off (the remaining engine will give a TWR of 1). I know it probably wasn't necessary to have a TWR of more than 1 at this point, but just in case...


Apoapsis reaching target of 100km, meanwhile deploying solar panels:


Apoapsis safely above the atmosphere! Before reaching Ap, the now unneeded reaction wheel is dropped, to save every last bit of D-v:


Preparing for the circularisation burn:


And we're in orbit!:D With around 500m/s of delta-v left (MechJeb says 426 because it is assuming the two radial engines in the same stage are active)! This small capsule and engine are all that's left of the 900t monster.


Planning the docking with the RIS (Reusable Inter-planetary Stage), which was also used to bring the lander for the Dres mission to Dres, and bring the (same) crew back home.


Approaching the RIS:


And the docking was successful! As you can see, we have more than 7000m/s of D-v at our disposal:


Well, this huge burn would get us quite close, but it would take 20 minutes (ignore what the timer is saying, it messed up), which is impossible to do accurately in low orbit.


So I break it down into a much more achievable 1500m/s burn, and I'll burn the rest later.


Burning out of Eve orbit:


Only one panel deployed, due to the previously discussed issue...:huh:. Looks like some sort of solar sail...


Great! Now all we need is a tiny 4000m/s burn and we'll be pretty much spot on... (this is why you wait for launch windows:sticktongue:)


Halfway through the burn, which took around 10 minutes:


After the burn, Lodory and Edvis enjoying the view as they shoot out of the Eve system at 6000m/s.


And we still have 2000m/s at our disposal, even though according to MechJeb it's negative... Must be because it's calculating from the lander can's point of view, which is pointing the wrong way relative to the LV-Ns.


And the first manned mission to Eve was a complete success! I may or may not post the images of the arrival to Kerbin, but it's nothing special, I just used an aerobrake to circularise, and the crew were brought to the KSC with an SSTO Spaceplane.
However, I may eventually post a mission to Eeloo, using some parts in the Interstellar mod, so that should be interesting...:)

Edited November 30, 2015 by A35K

[Wallygator]

That was nice.

Well documented, but not too much fru fru unnecessary stuff. Nice to see a well reported "vintage" mission report in these current times!

[A35K]

On 26 November 2015 at 23:51:21, Wallygator said:

That was nice.

Well documented, but not too much fru fru unnecessary stuff. Nice to see a well reported "vintage" mission report in these current times!

Thanks! Unfortunately, it seems the new forum has removed all of the pictures...

Edit: Nevermind, just opening it and saving it returned the pictures.

Edited November 30, 2015 by A35K