Sending a shuttle to jool

[MagicFireCaster]

Hey guys, so i've made this thread since i wan't to send a shuttle directly to jool with a 87 tons payload (1 lander 4 probes and 4 kerbals and fuel) and i want to know if it's viable or if i should do some changes?  i think right now it has around 3481 m7s of Dv to work from kerbin orbit (i think it isn't enough)

Here is a pic of the shuttle

The plan so far:

I will refuel the ship once it is in orbit 

Use the docking ports around the ship to dock extra fuel tanks (and maybe engines) for the transfer burn,

I'm considering changing the vector engines for another ones in orbit (that would requiere replace them using docking ports so i would have to change that in the VAB), also i'm thinking maybe i would be able to aerobrake due to the parts being highly heat resistant, will they do? 

Is it  going to work like this or should i build a bigger ship to help it get into jool orbit? 

PD: I want to get THIS SHIP to jool, not another one, i want to try the challenge of getting a shuttle like this far away, so i'm just considering desing changes, but not replacement.

 

[Geschosskopf]

That's a nice looking shuttle, but the question of its viability for a Jool trip is dependent on its amount of delta-V, which you didn't mention.  You need considerably more to get from LKO to Jool and back than you do to get from the ground to LKO to start with.   I don't see that much fuel aboard your shuttle.

Do you use a mod that tells you the amount of delta-V in your ship, and delta-V maps that tell you how much you need for a given trip?

[ElWanderer]

LKO to Jool, I'd allow 2.5km/s (plotted burn of about 2km/s, plus corrections and an inclination change). Getting into medium Jool orbit without any gravity assists cost me 1.5km/s last time I did it, but by slinging around Laythe or Tylo you should be able to get a Jool orbit for much less. Still, that doesn't leave your shuttle much if any fuel to do anything further. Is your final destination just any Jool orbit or are you hoping to visit the moons with the shuttle? Are you intending to come back to Kerbin?

[MagicFireCaster]

As i said before i have around 3481 m/s of delta v  from lko after refueling the ship (i did the math myself it could be wrong), maybe i'm going to do some fly-by to some moons, just to drop the probes in them.

[KerikBalm]

23 hours ago, MagicFireCaster said:

Use the docking ports around the ship to dock extra fuel tanks (and maybe engines) for the transfer burn

If you attach anything to those docking ports, as the attachement would be perpendicular to the thrust line, you would need a combination of very low attached mass and/or very low craft acceleration to make it work. If you want to dock things and do significant maneuvers, they should be "in line" with the thrust, and ideally, you'd be pulling the payload, not pushing.

If you want to get 87 tons to Jool orbit, you'll probably want to make use of a tug... a big tug

[Plusck]

18 hours ago, ElWanderer said:

... but by slinging around Laythe or Tylo you should be able to get a Jool orbit for much less. ...

Since accidentally getting a good Tylo flyby once, every single one of my Jool missions has used exactly zero m/s dv to get a capture into Jool orbit. Generally with a Pe between Laythe and Vall and an Ap close to Bop. For a maximum course correction of about 80 m/s halfway there.

Edited January 10, 2016 by Plusck

[MagicFireCaster]

1 hour ago, KerikBalm said:

If you attach anything to those docking ports, as the attachement would be perpendicular to the thrust line, you would need a combination of very low attached mass and/or very low craft acceleration to make it work. If you want to dock things and do significant maneuvers, they should be "in line" with the thrust, and ideally, you'd be pulling the payload, not pushing.

If you want to get 87 tons to Jool orbit, you'll probably want to make use of a tug... a big tug

I need to think about something else to send it then 

[fourfa]

Things I might try: 

-keep it simple; don't try to aerobrake. Just bring enough dV. 

-put a large docking port under the top 2.5m nose cone. Jettison the cone before Kerbin circularization. Then you have a more or less inline docking port

-attach additional big 3.75m tanks, but empty them in VAB so you just barely get to orbit. Then refuel in orbit for more dV than you could have launched to LKO without docking. 

-you can gain a large amount of vacuum dV with more efficient engines (Rhino for instance) and make up the sea level deficiency with SRBs or radial boosters

[Warzouz]

On 10/1/2016 at 4:23 PM, Plusck said:

Since accidentally getting a good Tylo flyby once, every single one of my Jool missions has used exactly zero m/s dv to get a capture into Jool orbit. Generally with a Pe between Laythe and Vall and an Ap close to Bop. For a maximum course correction of about 80 m/s halfway there.

Fun thing, I did exactly the same. I got a Tylo + Vall + Laythe flyby and ended on a AP near Bop orbit that managed to be also the AN or DN with Bop (very cheap plane change. All that for less than 20m/s (in 3 burns). Then I could go to Bop for 400m/s.

[Plusck]

1 hour ago, Warzouz said:

Fun thing, I did exactly the same. I got a Tylo + Vall + Laythe flyby and ended on a AP near Bop orbit that managed to be also the AN or DN with Bop (very cheap plane change. All that for less than 20m/s (in 3 burns). Then I could go to Bop for 400m/s.

Nice. Right now I have a ton of ships converging on Bop (needing fuel, low TWR mining ship among them) but the planes are all out of synch with the arrival angle so I can't get a decent (i.e. free) plane change. I've mostly given up trying to get the orbits to settle down post-encounter so I just float by Tylo and sort my orbits in detail afterwards.