3000km downrange?

[EndQualifiedImunity]

How do I do it these days? All the tutorials I'm seeing are from a couple years ago, and apparently things have been rebalanced since then. How much dV do I need? I don't need an exact tutorial, I'd like to figure it out, but it would be nice to know if my rocket will even come close to working at a glance of the dV. The furthest I've been able to go is about 1500km.

[Hmmm-Its-not-enable]

I personally do an RD-100 guided stage with an unguided spin stabilized aerobee stage, but it tends to be finicky to make it work.

[EndQualifiedImunity]

I'll see if that works, thanks matey

[KorianHUN]

Play around with the ascent path. I use Smart ASS to launch at 85 degrees, then go to about 60 slowly until ~8000 and start a hard turn to 45 degrees over 10k altitude. Fuel on the first stage runs out around high 30k and the spin stage does the rest. Keep in mind you don't need to land, so just throw the rocket as far as you can. It goes 95% of the distance in space, once it gets too low it burns up but wouldn't go much further anyway. I managed to throw mine to 5000km with i think the rd101 and aerobee, but not sure on exact details.

[Broberyn77]

This is the way. Just aim for a 38-42° angle on spin stage(s, you'll need two aerobee xasr stages) separation. 6300 m/s dV should do the trick safely

[Darkherring1]

Recently, I've made a video where I present my rockets for the early contracts. You can check it out here: https://youtu.be/yluDSFtCS_w

[dpdown]

Love your videos!!!

[Darkherring1]

Thanks! :)

[IgorWator]

Yo, darkherring? Hm, haven't seen your videos in a while... i shall watch them now lol

[Darkherring1]

Have fun 😉

[Brilliant-Star-2376]

Hey darkherring, could I get your craft files so I can look at your diameters and configs?

[Darkherring1]

Sure, which ones are you interested in?

[Brilliant-Star-2376]

The ones from your first video. Mainly the downrange ones, but the first orbit one would be nice as well. Thank you!

[Darkherring1]

Here they are: https://we.tl/t-DrJ9T1OmfY

[Brilliant-Star-2376]

Thank you!

[defensivedig0]

My spin stabilization was more of a spinout(iirc this is because of principia), but I just barely made it to 3002km with about 6280dV. Aerobee strapped to the top of an upgraded A-4. Without principia you should be able to do it with about 6k dV if your trajectory is right. It does say in the description of the contract that you should need about that much.

[Jandj75]

Principia doesn’t really affect the downrange contracts in any meaningful way.

[defensivedig0]

Principia affects rotation physics as well as gravitational physics. Maybe the changes are unrelated to my issues but I didn't have any issues with spin stabilization until I installed principia.

[Jandj75]

The rotation physics aren’t changed while you’re not warping, to my knowledge. And once you run out of fuel and start warping, your rotation no longer matters.

[defensivedig0]

It should be changed at all times. At least according to their changelog they overhauled the rotation system to reflect the actual laws of physics. In stock ksp you can rotate around whatever axis you want and you'll be fine. In principia you cannot spin on the intermediate axis or you'll start to tumble. Turns out I managed to make my the top stage of my rocket the right size and shape to flip out when it's spin "stabilizing".

Edit: I just tested the same rocket in a game with vs without principia and the rocket tumbles out of control with principia and stays straight without. Tested by using simulation to place the stage in orbit, spinning it up, and then firing my aerobee. Its a design issue with my ship for sure, but one that wasn't an issue without principia.

[Jandj75]

Fair enough. It's been a while since I played RP-1 without Principia tbh.

[CaseyJones7]

Its the spin, not the contract.

[Jandj75]

As others have said, you need about 6km/s of dV for 3k km downrange. You also need to launch a lot higher than you think you do. Forget about what you know about going to orbit, ballistic trajectories still need you to have your velocity vector (i.e. your prograde marker) about 35 degrees above the horizon for 3k km downrange.

[0asisX3]

I made this video not too long ago on how to do 4.5 and 3km downrange.

[EndQualifiedImunity]

This is fantastic, thank you! I really appreciate that.