KSP2 Aero-model discussion thread.

[DA299]

So, I haven't bought the EA yet, but here's my question to the people who have already played it for a while: what changes do you see in the aero-model?

I'm a huge plane/spaceplane guy, so naturally I would be interested in knowing the state of things. Do parts still have drag-cubes, or does KSP2 finally use a holistic voxel approach to calculating drag, like in FAR?

How do airplanes stall? and is ground effect being modelled?

Anything other that is remarkable in the new aero model, please do enlighten us all.

[Periple]

I haven’t done any detailed exploration but it seems to be very similar to KSP except somewhat better behaved. You don’t get ground effect or realistic stalls FAR style, but planes are overall easier to fly and more predictable to design.

[Vl3d]

My impression is that planes are much more stable now, but also less agile (you need higher angles for control surfaces). But it might depend on the speed and my design. Overall I think the aero model feels great for planes.

Edited March 5, 2023 by Vl3d

[RocketRockington]

8 hours ago, DA299 said:

So, I haven't bought the EA yet, but here's my question to the people who have already played it for a while: what changes do you see in the aero-model?

I'm a huge plane/spaceplane guy, so naturally I would be interested in knowing the state of things. Do parts still have drag-cubes, or does KSP2 finally use a holistic voxel approach to calculating drag, like in FAR?

How do airplanes stall? and is ground effect being modelled?

Anything other that is remarkable in the new aero model, please do enlighten us all.

From my testing pre refund, it's a simplified version of the KSP1 model (or at least with more artificial guard rails).  It's still per part aero with artificial tuning around that, and no holistic occlusion, but now parts don't even have individual velocity.  Or maybe I was.misunderstanding what I was seeing, aero debugging is also less robust.

The game also seems to add some sort of artificial stability to craft.  Stalls are even more gentle/nonexistent vs KSP1.

Definitely easier for newbies to use, but also seems like it's even a notch less realistic than KSP1 aero.

Edited March 5, 2023 by RocketRockington

[schlosrat]

Planes may be easier due to aero, but let me tell you rockets are most definitely not. That may not matter to you if you're playing the game mostly for planes, but control of a rocket on ascent is now noticeably harder. Double or triple the reaction wheels, if you're bothering to rely on them at all while you're atmospheric. If you slap on enough to control your rocket in the air, you'll have far more than you need once out of atmo. Just forget about the so-called stabilizers and go for control surfaces. I'm not sure fairings even do anything at all other than sit there and look pretty.

[Vl3d]

5 minutes ago, schlosrat said:

Planes may be easier due to aero, but let me tell you rockets are most definitely not. That may not matter to you if you're playing the game mostly for planes, but control of a rocket on ascent is now noticeably harder. Double or triple the reaction wheels, if you're bothering to rely on them at all while you're atmospheric. If you slap on enough to control your rocket in the air, you'll have far more than you need once out of atmo. Just forget about the so-called stabilizers and go for control surfaces. I'm not sure fairings even do anything at all other than sit there and look pretty.

I tend to not agree, I feel like rocket aero is more realistic now. I have encountered no aero issues with getting to orbit (except for bugs). But I think aerodynamics shape is very important now and also a thought out ascent profile. Other players have mentioned that there's a lot more drag now. I think that's great! No more...

...horror.

Edited March 5, 2023 by Vl3d

[schlosrat]

More drag, perhaps, but more realistic, I don't think so.

With the biggest engine in game and a TWR north of 1.5 I can easily get up to speed quickly and don't even being a turn until at least 100 m/s. That motor, with it's gimbaling, should be able to handle an ordinary rocket just fine without even needing fins, or only minimal fins. Do you see fins on a Falcon 9? An Atlas V, or a Delta IV Heavy? Nope, nope, and nope again. And I can assure you they begin their turns a lot earlier than I can in KSP. I live in the Space Coast area of Florida and watch/photograph lots of launches. They start their turns early, and they don't have any stinking fins. If I build something that looks about like a Saturn V and use the so-called size MD stabilizers (looks about right scale-wise), that sucker's gonna flip. If I take off the so-called stabilizers and put on control surfaces that are about 3 -  4 times bigger (visually speaking - though still Size MD), then I may get to orbit without it flipping on me.

Here's a shot of the LV with the rover and no fairing - this get's to orbit, but it's tricky.

I fly rockets. I mostly fly them to the Mun and Minums right now, and I land things on both targets. Lately I've been landing rovers. I just put a large rover near the easter egg on Minmus, and that was fun! Interesting thing with that launch - I tried the LV with a fairing over the large rover and it flipped. It had more than enough dV, TWR, and the fairing was just big enough to encompass the rover and it's wheels. Picture something like what's shown above except with one less large reaction wheel and with Skippers for the strap-on engines - everything else the same except it had a fairing. It was not anything like the comically large fairing posted above. I made the changes seen above to the rocket and ran it without the fairing, but larger control surfaces, bigger strap-on engines, and double the first stage reaction wheels. With a very late gravity turn I got it to orbit, but it was a complete PITA on the way up.

So, while the new aero may be making things easier for those flying planes, in my experience it's certainly not making things easier or more realistic for those flying rockets. I'm happy that the new aero works so well for planes. It's nice that it's easier now for those. I sure would be nice if rockets could get some of that love.

Edited March 5, 2023 by schlosrat

[RocketRockington]

Take this with a grain of salt as it's second hand information, I didn't test this, but reports on reddit say the fairings don't shield parts inside them from aero at all.  Fairings may currently be decorative items only.