Jool: My First (now second) Build

[Aevitas]

Previous (failed) attempt post:

Spoiler

So, yesterday, spurred on by missions, decided to do a Jool mission. Specifcations of the mission below, put in spoiler tag in case you do not want to see the specifics for actual mission.

Spoiler

The mission was simple; orbit Jool in a 300km~ circular orbit with main station (beefy antennia), and undock the small probe and send it down to Jool's atmosphere to take a sample,  completing two missions at once.

 

I've played KSP1 for nearly 600 hours. I've not once set foot deeper past Mun, Minmas, Duna, and Ike. In KSP 2, I want to change that.

So I built this thing:

I should have enough Delta-V to intercept & orbit Jool just fine. However... that is not what happens. There is some game breaking bug with delta-v calcuations or usage that is happening with radial tanks. Seems to horribly effect Nuclear engines.  I'm not sure how to counteract this, but I'm going to give it one last shot. I think my only chance is using vertical only, and no radial tanks. I usually build like the image above to force my rocket to be smaller & more compact. No idea how I'm going to lift this into LKO; good thing I tested it before trying to build an ascent vehicle. 

 

-- Mission Complete!  --

Finally, after 600 hours in KSP1, and 30 hours in KSP2, I have reached outside of Mun, Minmas, Duna, and Ike. Finally, I've reached farther.

After the failed build above, I decided to rebuild everything. Using radical decouplers with fuel-feed off and only vertical tanks in a single line, I developed my craft. Lifting it into orbit was surprisingly trivial, though I had a few issues of spontanious wiggle exploding the vessel on the pad, and some strange force in the upper atmosphere causing uncontrollable spin. And the fairing naturally did not protect from heat. 

I forgot to screenshot the ascent vehicle, but I've posted 3 screenshots below of the end of the trip

Spoiler

 

Edited January 17 by Aevitas
Added completion

[Poppa Wheelie]

22 hours ago, Aevitas said:

avoid the delta-v calc bug

Some options:

• Attach all radial tanks with radial decouplers instead of directly tank on tank
• Manually calculate your dV using the rocket formula

[Icegrx]

This bug is easily bypassed by manually calculating Delta V

[Aevitas]

5 hours ago, Poppa Wheelie said:

Some options:

• Attach all radial tanks with radial decouplers instead of directly tank on tank
• Manually calculate your dV using the rocket formula

 

1 hour ago, Icegrx said:

This bug is easily bypassed by manually calculating Delta V

Δv = ln ( fueled mass divided by dry mass ) * Isp * 9.80665

9.80665 being kerbin gravity; since this is being used in vaccum only for Kerbin escape/intercept/Jool Orbit, do I not use the 9.81? 

Do I need to calculate the total ISP of 8 NERV engines?

I did not think about manually calculating the Delta-V. Thank you both

[Poppa Wheelie]

40 minutes ago, Aevitas said:

do I not use the 9.81? 

You still use the 9.81.  This is required because of the way Isp is defined.  I don't know the details, I can't show you the math.  But you must still include the 9.81.

[Poppa Wheelie]

You may find this helpful.

 

[Aevitas]

18 hours ago, Poppa Wheelie said:

You may find this helpful.

Thanks! I managed to do it via literally raising my orbit expectations, instead of getting 350 kilometers circlular orbit I was roughly 3000~ kilometers circle.

However that'll be a huge help later on, my ultimate goal is for a Jool-5 type mission (way later) and maybe other challenges. Would absolutely need something like that for then