Making Better Rockets

Tuning your rocket engines effectively and using the right fuels can also greatly increase efficiency. My upper stages are generally always hydrolox as you can get away with using smaller engines in space plus they are a lot more efficient. Low throat size and as large as practically possible nozzle length when tuning engines for vacuum use will produce more thrust per unit of fuel used.
On the surface, you need raw power - energy dense fuels such as kerolox or methalox paired with a gas generator or full-flow staged rocket motor with plenty of thrust will make sure your rockets get off the ground. For this, high chamber pressure, large throat and a shorter nozzle will make your rocket more efficient at sea level. I tend to aim so that my first stage gets me at least 15-20 km ASL. Then a second ‘intermediate’ stage finishes ascension and circularises my Droo orbit. From there my third stage will do all my interplanetary manoeuvres then a final payload stage will have small low-powered engines and enough fuel to fine tune its orbit once it gets to its destination.

I have been doing the Tydos moon missions in career mode. The hardest part is getting there in time as Droo can be in the wrong position for a simple transfer orbit burn once leaving Droo’s SOI. the mission timelines usually don’t allow for the time to do a chain of gravity assist manoeuvres to reduce delta-V budget unless of course the mission is accepted in a position where the planets are perfectly aligned. My current rocket for these missions at this point in time is a Saturn V style spacecraft. It is a beast - 106 m tall, 1200 tonnes with a total delta-V of around 11km/s and costs around $110M plus launch fees.
I have found if I do the mission in three steps, I tend to succeed. First step is to get into orbit around Droo, this is my “parking orbit” which is around 120-150 km ASL. At this point I wait until the craft is in a position to do a prograde ~1.4 km/s burn to escape Droo’s SOI. This gets me into a roughly circular orbit around Juno. Next I try to find the closest position to do another ~1.4-1.7 km/s burn. This can range from a purely prograde burn or incorporate some burn on the radial axis to pull the orbit path backward or forward so the apoapsis is closer to the SOI of Tydos. Then I fine tune the burn node so that the craft enters Tydos’ SOI and goes into Tydos’ atmosphere to perform an aerobraking manoeuvre. The orbit inside Tydos’ SOI should have a periapsis of around 2700 km meaning the craft will have an orbital velocity of 24000 m/s and aerobrake enough to reduce the orbit from hyperbolic to an apoapsis of between 150-300 Mm depending on how low into the atmosphere you go and also how un-aerodynamic your craft is.
When around Tydos your final stage should have plenty of delta-V because if it doesn’t, you won’t be making many orbital adjustments due to the intense gravitational pull of Tydos. Even a small orbital adjustment such as inclination of a few degrees can require hundreds of m/s of delta-V if your craft is close (inside the moons’ orbits) to Tydos.

So I would recommend you start learning how to do satellite rendezvous, because if you are going to send a full on mission to let’s say urados, you need to assemble a ship in orbit with not one, but many rockets. Once you finish that, you can have landers and droods launched to the vehicle and it can service as a mobile space station for your mission.

It’s however a WHOLE new story when sending a manned mission there. It’s almost impossible to send a Apollo-style mission with the whole mission in one rocket. So if you even want to get close (let’s say we wanted to land on boreas or miros) you would need to do a separate launch to have a ascent rocket. But that still would be tough.

Now considering you don’t want to use tinker, I have sent many probes to Tydos with my big rocket. Tydos is kind of the barrier where it starts to get almost impossible to make a good enough rocket to send a probe to Urados.

I have send probes to Urados very few times. I did this by aero breaking, but if I haven’t used aerobreaking I would have never got that probe there. Which I realized that was close to the barrier of vanilla capability.

@AstronautPlanes alright thanks @QarabinaKa ill see about transfer orbits

I battled quite a bit getting to Tydos, but I eventually managed to do it with a rocket with Delta-v of about 10km/s. My method was to get Tydos overhead at dawn, lock pitch at 90° and just burn straight up until I get into a transfer trajectory. Probably not the most efficient way but it's the only one I can get to work for myself.

@speediplayz You can go ti settings and configure the max time warp, if you need more help you can contact me on Discord

@AstronautPlanes cant thrusters only work at 2x max unless its ion? (and no im not making a giant ion thrust rocket)

@speediplayz Just make the nozzle big, make it as powerful as you can, and have time warp to the maximum (in KSP it was boring because there was 4x time warp, SR2 has 10x so it doesn't get that boring)

@AstronautPlanes I dont see how nuclear engines are so good, im not having any luck with them

@speediplayz Docking modules is probably the best option, use nuclear engines btw (liquid hydrogen is the best)

@Gabepasc Id needa practice transfer window stuff as im not too good with it, so as bmcclory said probably the simpler stuff

@Bmcclory The rocket does not need to be huge if you know when the transfer window is but I cannot find anything about that for simplerockets2.

@Bmcclory thanks, ill see if i can make the big rockets as i am horrible with rendezvous

@s5ehfr9 gravitational slingshots will take alot of time for me to get good at, and I will probably just stick with regular rockets. @Gabepasc It probably would be a good idea for me to reduce the size of my satellites

I just made it to Urados by building a huge rocket with a very small probe. The first time I made it there I used 18 km/s of deltaV.

First u need to be able to put hundreds of tons of payload into orbit, so u have enough delta-v to go to places u want to reach. If that's not enough, u might need to use orbital mechanics to ur advantage (like oberth effect and gravity slingshots). If that's still not enough, try using non-combustion rockets, which have higher impulse.

@NoIDontWanna im pretty sure thats kinda obvious