Jool accent, the imposible chalenge.

[magnemoe]

After the grand tour with less than an 100 ton ship it looked like it was no more challenges left.

Until someone showed it was possible to get out from ground level on Jool using only stock parts. However the ship was hyperedited into Jool orbit and the lander looked inefficient.

So I decided to try this myself.

I had some experience with Jool accents but then using the pretty overpowered Hooliganlabs balloons to take me out of the thick part of the atmosphere, reducing dV demands to around 12000 m/s who is doable as Jool has an pretty low gravity so you can use LV-N for the majority of the burn.

I build and tested an lander.

Stage 15 to 9 is groups of either 7 or 5 aerospikes under 2.5 meter tanks. I tried using the stock 2.5 meter to 4 x 1.25 meter adapters, however an major issue with the Jool accent is the overheating of the aerospikes down in the 15 bar and 900 degree atmosphere.

Puting them on spikes let me increase throttle from 66% up to around 80% who helped a lot so I did this with all aerospikes.

Stage 8 to 3 is aerospikes with 1.25 meter tanks. 2 and 1 is LV-N who is fired at 31 km where the pressure is 0.8 bar and the LV-N has similar ISP as the aerospikes.

stage 0 is 48-7S and 45 liter tank probe core and seat.

---

Lander in LKO during during refueling 7 of 8.

it was launched as an SSTO, the orange drop tanks was used to let the outer engines burn longer and will be used during the Jool transfer, I will need 8 more orange tanks for refueling in low Jool orbit so I need to make an huge transporter to get them where.

[Geschosskopf]

Egad, that thing probably produces its own gravity . I look forward to seeing more of this.

[thatsmessedup]

WHOLLY MOLLY!! Jeb has gone insane

[magnemoe]

More is coming, first some more shot of the lander.

Top, Shows the structure pretty well, first 8 droptanks, then 10 2.5 meter stacks with 7 aerospikes, 4 with 5 aerospikes, followed by 12 1.25 meter stages and the three nuclear engines.

I had two more stacks of LV-N but forgot the fuel line so I jettisoned them, even with 24 LV-N trust then fully filled is an amazing 0.1g so they would be missed.

However the ship is hard to launch, rolls easy at start of gravity turn, just forget to use mechjeb for launching it.

Bottom with 102 aerospike engines.

An launch attempt.

This one was deorbited because of another bug with the piping, Let me check out the crew escape system who worked as Bill's is happy for.

An very kerbal inversion, on the top picture you can see the orange braking parachute, an one man landing can below, I can decople the landing can and open all parachutes, this will pull the landing can fast uppward it I move in the direction of trust, this is also how I plan of getting rid of the landing can after arriving at Jool.

[magnemoe]

Other systems used during this project.

First the refuler.

It takes 4.5 orange tanks with fuel to 80 Km orbit and I have so far used 7 of them to refuel the lander. Will need one more as I used two orange tanks lifting the lander to an 300 km orbit, the burn to Jool will take over 25 minutes so I can ot do it from to low orbit. Waiting with the refuler as I might use it for two targets.

Second the Jool fuel transfer ship.

10 orange tanks, 4 large gray tanks who will be dropped during the burn. It will deliver around 8 orange tanks with fuel to Jool orbit.

This was a interesting situation, I used an mainsail on the center tank go give better twr during launch, two 180 liter tanks to get it so far back the thick top part of the mainsail is at the neck of the LV-N, it was disabled and dropped then I reached high enough speed to don't need the TWR however during trust it was stuck, it worked fine to drop it during an static test, Luckily it moved away from the ship during warp.

Here is an earlier version of the launcher.

An picture taken some seconds later, also the most common result of the launches even if most reached an higher attitude.

Next task now is to refuel it and bring the crew module who will be docked in front of the fuel carrier, before launching the two ships to Jool

[thatsmessedup]

all i can say is holy motherF##K!

[magnemoe]

Refueling The bitch. official name for the Jool fuel transfer ship because its 480 in LKO ton is the second heaviest thing I have launched using stock parts. 1600 ton on pad, 697 parts, it needed to refuel around 6 orange tanks or 200 ton fuel in orbit so it was not so insane.

Launching the crew module, calname doghouse. It was just added on top of the second refueler who will top off the beast, collect Jeb, dock doghouse to the bitch and top it up with fuel after it has been moved to 150 km orbit awaiting launch.

First launch became "testing the escape system" it worked well, the launcher did not.

Doghouse is its own 13 ton spaceship, it has 2500 m/s dV so it should be able to get back from Jool on its own, its also able to do an powered landing on Kerbin however it lost one of the engines here so I had to separate the command module and do an parachute splashdown. Anyway an escape system on the escape system is good safety.

Topping off the Beast.

Jool lander is named The Beast and is 1416 ton and 788 parts, it was 1706 ton and 856 part on pad, however the only thing dropped from it was the 16 solid fuel boosters.

Jeb on Eva back to doghouse.

it gives some details of the center of beast, the cube probe is to easy set the direction for LV-N trust for the transfer.

Look like Geschosskopf was right an the beast has gravity, after undocking doghouse prior to Jeb Eve I did an 1 m/s backward trust with the rcs however doghouse moved back.

Docking Doghouse to Bitch and transferring fuel.

Bob almost forgot to do the Apollo twist and move doghouse around before docking with Bitch.

Waiting for Jool transfer, Jeb is strategically placed below the Toothbrushes and Board games.

Bob is still angry because he got the blame for not rotating doghouse.

This also answer if the kerbals eat or not.

[thatsmessedup]

how many orange tanks did you bring up at once? 6? I thought my 4x orange tankard hauled a lot.

[magnemoe]

how many orange tanks did you bring up at once? 6? I thought my 4x orange tankard hauled a lot.

The default launcher is five, one core and four side tanks, an pancake in bottom to avoid overheat, it lift 4 and an half orange tanks to target at 80 km. launch weight is 1108 ton.

As I have launched a lot of these its very fine tuned.

during the default launch it drops the last booster set a second before the end of gravity turn, circulating is 230 m/s.

[magnemoe]

To Jool, as the beast would use half an hour on the burn I did one pre burn who lifted my Ap almost to Mun orbit, as the 2.1 degree plane change is pretty much at kerbins location during the launch I rolled the plane change into the launch.

I realize I should have done that maneuver close to the Ap and I could have saved over 200 m/s.

Dropping tanks:

The last set.

Burn was an totally pain, because of the slow frame rate it probably took two hours real time, luckily I has two screens so I put KSP on the secondary and just checked then it was time to drop tanks.

However I used 3 and a half orange tanks of the inboard fuel, pretty much on budget.

The bitch was an nice dog once in orbit, her I drop two of the drop tanks, the two pancake tanks below the lander is drop tanks for the beast for the deorbit burn. However as I have 8 45 liter tanks below the nuclear engines and two for the power modules I doubt I need them. The good news is that the bitch is above budget and has 6 orange tanks of fuel left.

[magnemoe]

An last picture of Kerbin: All the stuff in LKO is refueling probes with 5 orange tanks.

Incoming to Jool:ships is one day from each other, almost so I had to do an burn to let bitch arive later.

Stand by for aerobrake

Bitch is incomming:

I found I put the ships in an too low orbit, it was an nightmare to dock as the relative speed indicators was jumping all over, increasing Ap to over 200 km helped, do did decoupling the lander and the side tanks I didn't need as I had 10 45 liter tanks with fuel under nuclear engines and the power modules.

An tiny deorbit burn

Giving Jool an radiation belt.

Just my luck and Tylo eclipse just before aerobraking so I turned off SAS luclily beast was very stable during aerobraking, I also got it during accent so I had to disable most sas modules and move power to the central batteries

Note that you can not see Tylo,

Out of the eclipse so I drops the power modules

Start of aerobraking:

The power modules behaved very strange, first they dropped behind, then they start moving forward with high speed, my theory is that the solar panels generated a lot of drag slowing them down, then the solar panels broke the low part count compared to beast gave them lower air resistance so the past it.

Aerobraking was pretty gentle max at 4.5 g.

Ship has slowed down and Jeb moves from the command module to the seat.

I tried to take an picture of the command module getting ejected but it happened too fast.

Into the darkness.

[magnemoe]

Getting out again: Ignition

Dropping bellow zero attitude and braking, the effect was pretty cool

Dropping first booster set:

Continuing dropping boosters:

Overheat is an very serious issue down in the very thick and hot atmosphere, its also why I had an TWR of more than 2, you can not have more than 80% throttle.

Last of the 7 engine boosters is dropped, the stages switched from beeing restrained by overheat or air resistance while getting emptied.

Moving power to central batteries because of the Tylo eclipse who came again as I stopped.

Dropping 1.25 meter stages, pressuer is much lower and its cooler so no more overheat issues.

Activating nuclear engines as 31 km, here the air pressure is 0.7 bar and the LV-N has better ISP than the aerospikes.

Dropping the last booster set, looking good, I just has to reach 5600 m/s while keeping higher than 137 km.

Beast became easier and easier to handle during accent:

Orbit: Now I has to dock bitch and doghouse befor Jeb meet them.

As bitch has plenty of fuel left I plan to tour visit some Bop, Pol and probably Vall before returning.

[magnemoe]

Album with more pictures during the expedition:

http://imgur.com/a/dahmU#0

[magnemoe]

Back to doghouse and an mission extension, as bitch was almost half full it was decided to visit Vall, Bop and Pol, however at Jeb approaches bitch he found that something was wrong.

Yes it miss one of the four double tanks and four of the engines.

It must have fallen off as I did orbital adjustments after docking, if you let mechjeb do the burn it tend to wobble the ship a lot during the final adjustments of the burn.

Quick test show that the ship was workable with trimming fuel, as its wildly asymmetric it would be hard to use manual however I will not let mechjeb do fine tuning on large fragile ships anymore.

Anyway off to Vall where they had to show off.

Jeb wonder why the lander only has one solar panel, and Tylo sneaks in again

[Accelerando]

I know this is an oldish thread now, but this is amazing. Hats off to you.

[oggylt]

Wow, this is glorious! Eve is nothing compared to this

[Th_]

How could you even fit that many aerospikes on a vessel? The most engines I've ever had on the same ship, including the launch stage, was 12!

[turkwinif]

Holy cow, that is one heck of a ship! You must of been very patient and lucky! The Kraken would've swallowed that ship whole for me if I ever tried something at that big of a scale!

Now, the only thing left is...to land on...THE SUN! (if at all possible )

[HafCoJoe]

Yes indeed this is quite impressive!

[Whovian]

Holy sniznizl! I'd considered this, but figured it was impossible without mods like KSPI due to the thick atmo.

Good job!

[fespinor]

Hi, I have a question, because when I try to land on jool , the screen goes black , and the ship explodes ? Someone else has had this problem? And anyone know what causes it ?

[psyper]

Hi, I have a question, because when I try to land on jool , the screen goes black , and the ship explodes ? Someone else has had this problem? And anyone know what causes it ?

Technically you shouldn't be able to land on Jool as it "shouldn't" have a solid surface - much like its analogy in real life - jupiter or saturn - no probe is able to land on it and should be crushed by the atmosphere. Saying that there is a KRAKEN who lives down there and if you're very lucky he will let you land upon his back but its only at his whim and for no reason he will crush your tiny ship in a snap.

[magnemoe]

Technically you shouldn't be able to land on Jool as it "shouldn't" have a solid surface - much like its analogy in real life - jupiter or saturn - no probe is able to land on it and should be crushed by the atmosphere. Saying that there is a KRAKEN who lives down there and if you're very lucky he will let you land upon his back but its only at his whim and for no reason he will crush your tiny ship in a snap.

Back in 0.19 Jool had an actual surface you could land on it however the ship would be thrown around and be destroyed in in short time of unknown reasons.

I managed to land Jeb on this surface using an airship and a kas winch. Some other managed to plant a flag.

This was changed in 0.20 or 0.21, no surface and getting at some negative attitude destroys your ship same as if you fly less than 1.4 km from sun.

Game has kill zones below the surface purpose of this is to crash crafts who hit bodies fast or under high time warp and could pass the surface between calculations.