Wubslin

I can handle early 2023!

Bless me, for I have sinned...

Damn, this is a good one. And cool to see a face put to the name with Chris Adderley (AKA Nertea, king of the KSP modders) for the first time. Also, I totally called it that the torch engines would be for smaller brachistochrones in-system like in the Expanse. Any word on if we'll be able to include the flip in the timewarp? Edit: Wait. Does this frame seem to show you guys are modeling relative stellar motion about the galactic core???

Wow, that's looking really good.

Bro what even was that omg

Adding NFTs to KSP 2 would be the worst thing I could possibly imagine. Like, worse than breaking the base game up into expensive DLCs and endless microtransactions bad. Do the people who want that crap in video games even understand why video games are fun? Does it compute for them that there might be reasons to do things other than getting more money? It's disgusting. I don't want to play a speculative slot machine-like stock market, I want to get into orbit.

Go watch the video I embedded. "Point at target" would not be nearly enough.

To everyone saying KSP 2 is a game about "peaceful exploration", if there's going to be multiplayer with separate ships you're basically denying an entire other dimension of gameplay that can exist. If I'm screwing around with my friend in cismunar space and I go "Minmus is MINE muahaha, attempt no landing there!" do you think the game will be more fun or less fun if we both are equipped with the proper tools to challenge or defend that claim? Peaceful game worlds or passive mode ships can always be a single context menu button away. Maybe KSP 2 shouldn't come with striker drones and attack lasers but at the very least, probe cores should be able to continue to follow SAS commands after you tab away from them (and maybe also have a proportional aiming based 'face target' mode too!)

Oh crap, I found something better! There's been a recent kickstarter for a 6DoF joystick by a group called Sublight Dynamics, and it looks far superior for the application of flying. From what I've read, it's easier to avoid having motions bleed into different axes and you get a better range of travel. Last we heard from these guys was a few months ago, so it doesn't seem like they're vaporware or a scam or anything. I would expect this to easily integrate with joystick controls, so long as RCS translation can also be assigned to analog axes.

Hey, every word I've heard says these things aren't great. But they literally do have a monopoly on 6dof controllers like this. Like I said, I'm not trying to shill for them.

To those who are unfamiliar, the 3DConnexion Space Mouse is this unique six degree of freedom mouse that allows three axes of rotation and three of translation through manipulating a joystick-type thing. From what I've read from several years-old forum posts, the compatibility KSP 1 has with the Space Mouse is crusty at best. I think it would be really cool for KSP 2 to have native support for RCS translation and rotation as well as attitude control in flight using these from the get go. I know Space Mice™© are uber proprietary and support would be enshrining this one highly specific company and all that, but c'mon. The Rocinante uses them as her main controls.

Even if it does have a metastable phase to it, it's still a monopropellant. John D. Clark's Ignition! tells us that when you're working on monopropellants not reliant on catalysis to decompose, you're essentially playing with primary high explosives. Metallic Hydrogen could be ridiculously dangerous if the slightest disturbance in the fuel lines resulted in your entire craft going up like a low yield nuclear explosion. Not to mention needing, like the devs said, to have a mixture of hydrogen and a dopant to make the substance reactive to a magnetic field and able to be contained by a magnetic nozzle. How would that even work? I'm not trying to argue the fuels' exclusion from the game, I'm just saying that it's basically the one propulsion mechanism whose physics aren't really understood. Even with nuclear salt water rockets, we're maybe a year of multiphysics simulations performed on big iron at some national lab like Los Alamos before we'd have a working design. Inertial confinement fusion is real technology. Nuclear fission is real technology. Metallic hydrogen? Remains to be seen whether it can exist without the weight of a gas giant bearing down on it or a wall of metal imploded by a nuclear explosion transiently rushing in on it.

They actually do not. That concern was speculation brought up while the details of nuclear aircraft propulsion were still being figured out and the theories surrounding their operation was in their infancy. It's still persisted, but if it matters at all just remember that a nuclear thermal rocket is essentially the same exact principle and those have been fired for long duration (just like nuclear jet engines have) without ill effect. It is of course true that they require high enrichment, but that much is true for any reactor designed to be compact or move around. If you had the ability to travel anywhere at will, by far the easiest way to come across multiple fission weapons' worth of high enrichment Uranium would be by going to the Moon or Mars in the near decades and stealing a Kilopower reactor. Remoteness replaces security up there. Of course planes are easier to steal but this is space frog video game. For your last point, it is true that shielding weighs a massive amount but it's offset by the fact that the plane needs to carry no heavy fuel otherwise. (Firing footage around 9 minutes or so)

Dang, that certainly doesn't sound trivial. Maybe if you took solids out of the game you could avoid all smoke trails!

Yeah. A lot of what I included in the images there is the XNJ140E nuclear turbojet, which was a General Electric project which made it basically all the way to the operational flight testing phase until Kennedy suddenly said "nuclear flight is de-cades away!" in his classic Boston accent before cancelling the nuclear aircraft propulsion program in 1961. Development for the engine soon ended, and to date a plane has never flown under nuclear power. The engine was expected to have an operational life of 1000 hours. The big fat thing I also posted, the HTRE-3 assembly, was successfully run at full power for almost 130 hours straight. There were a number of different designs that either had a turboshaft go straight through the reactor pile or else had multiple separate engine assemblies lead to a single reactor. It seems there never was a purpose-built compressor and turbine assembly and that the hardware used was repurposed from normal combustion turbojets. The website link there is the blog I got most of this information from, by the way. The Convair NX2 was a bomber with an interesting split tail design meant to accommodate three of those engines. Here's another good one: https://www.osti.gov/biblio/1048124 Hey look! A nuclear ramjet! No moving parts! Edit: oh and here's a last one, another Russian design that smartly avoids sending a turboshaft directly through the reactor pile (neutron embrittlement anyone?) but does it by sending the intake air and exhaust off to the side all funky-like.

Hey all! I just had a thought. The gas Brayton cycle we all know and love from such hits as jet engines, gas turbines, and that weird car that Jay Leno owns is a perfectly respected thermodynamic cycle. It's like the steam Rankine cycle without the cool phase change benefit but with none of the sogginess you normally get between the turbine and the heat source. Well, I was thinking about how jet engines don't have to have chemical combustors after their compressors, they just need something that cranks out heat. What else cranks out heat besides a flame? So yeah, it turns out there's been a lot of thought at one point into making nuclear jet engines. In fact, if you look up the HTRE devices you'll see they've been successfully run and even flown on real planes before! Just not at the same time though. How convenient would it be to have something that can breathe Eve's atmosphere but with more propulsive heft than just a simple electric propellor? And what better way to do it than with something like the above, a barely-shielded nuclear reactor with a turboshaft running right through the core and a chemical afterburner in the back for when there is oxygen in the atmosphere? I think it could make for a pretty cool part. Here's some food for thought: And the full report to anyone who cares: https://www.osti.gov/biblio/12555356-xnj140e-nuclear-turbojet-section-reactor

Hydrogen probably doesn't have a metastable metallic phase though, so you might want to label that as magic. It's even less likely that metallic phase would stay metastable if you tried to add impurities for magnetic confinement, either. I'm not mad though. It's just a game and that kind of thing is totally within the realm of possibility. I take the MST3K mantra on this stuff but if we want to shift into maximum pedantry overdrive, just remember that Kerbin is an impossibly small pebble with 1 G and 1 Bar at the surface. https://tvtropes.org/pmwiki/pmwiki.php/Main/MST3KMantra

If there's going to be even remotely realistic flying with Rask and Rusk, and I expect there will be because the devs have said there will be lagrange points, KSP 2 is at least going to have some kind of a system to model what's called restricted three body. Rask and Rusk may have a rigidly defined sphere of influence where patched conics apply outside and restricted three body applies inside. With restricted three body, both Rask and Rusk are on rails but the force they apply on your ship is a vector sum of Newton's law of gravitation i.e. "Gm1m2*r^-2". These two forces will be applied as impulses from iteration to iteration, thus effecting the motion of your ship. Due to there not being infinite accuracy in the values which describe your ship's motion, there will be a chaotic factor for values of time far into the future. In this video, you can imagine your ship as the yellow dot and Rask/Rusk as the pink and blue dots. Only with the same mass in KSP 2. In short it means that Rask will have a gravitational pull on your ship, and Rusk will have a gravitational pull on your ship, but neither Rask nor Rusk will pull on each other and your ship will be incapable of exerting its miniscule force on either planetoid. I'm no programmer but I imagine that if intercept came up with a working solution for restricted three body, they may be able to generalize and be able to do restricted n-body as well.

That's a really good point! I'm a complete novice when it comes to video game development and that didn't even occur to me. Yeah, this would be pretty much an ideal use for particle effects. You know how KSP 1 would always give your craft this piddly smoke column in an atmosphere that was made of individual puffs? And how if you got going fast enough or your PC slowed down they would be really obvious? Eliminating that effect and replacing it with a much smaller but more lively turbulent stream of fire that moves with your rocket would not only look better but be way easier on the hardware since you would only need a few examples of the effect at any given time. The coordinate system for this effect can be based on the engine itself. Presto! All you'd need to do after that is disinclude solid rocket boosters and you'd be set in terms of not having to deal with those smoke puff trails. Of course we all know that's not going to happen...

It looks amazing. If I had to suggest something, I noticed that the sea level exhaust plumes end by simply spreading out into a narrow cone of flow and fading. With irl plumes, at low altitudes you get a mixing regime where the exhaust begins to slow down and becomes highly turbulent as it moves downwards along with air that has been dragged along by the plume. This might be ridiculously hard to model so I don't expect the team to tackle that effect. It might be possible to simply fade the shock diamond effect and attempt to seamlessly blend in a second, more sputter-y and turbulent effect which can then be made to spread out and dim in a realistic-looking fashion, through. How hard that would be is definitely not something I would know. As for supersonic retropropulsion in an atmosphere, there's also some really distinct effects as the rocket exhaust exits the engine and forms a stagnation front as air slams into it in the opposing direcction. If you wanted to model this, perhaps you could take your transitional exhaust effects, truncate them at a certain distance, and then below the engine add a new geometric surface (like a backwards paraboloid) of similar textures and shaders to represent the exhaust backing up and flowing in the other direction. It could be pretty neat to see some falcon 9-style entry burns being performed in the game. Final note not so related to exhaust plumes, I have some questions about how we'll be flying these engines. I've got a few things that I've experienced through mods, and I have to ask, in order of increasing realism and inconvenience: Ullage thrust to start engines in free fall: I know this game isn't going to be hyper-simulationist and all that, but having to scooch forwards a little on RCS before performing a burn always gave me an increased feeling of immersion in the game. A setting to disable/enable this or possibly only including the feature in "hard mode" would be really cool. Thrust development: I imagine the base "normal mode" of the game will have throttle depth and response like in KSP 1 i.e. infinite and instantaneous, but again if there were going to be a "hard mode" it would be neat to have thrust come on gradually on ignition or application of throttle, and for there also to be thrust residuals when a given engine is turned off. NERVA engines for instance could have much more residual thrust than chemical engines out of the necessity to run hydrogen over the atomic pile to cool it back down. Throttle depth limits would also add to realism in a hypothetical hard mode. Limited numbers of engine starts: Going full realism overhaul here. Could such a hypothetical difficulty include limited numbers of restarts depending on the engine? This would be one of the most hardcore options of all. Possible inclusion? Honestly I'd be fine to see this one not make it into any hypothetical gameplay scenario. Again, you guys are pulling off incredible work and I'm definitely excited for the end result no matter what the team's vision for it may be. Keep it up!

I have a minor question. When we actually start building with these engines, is there going to be some kind of low profile mode like in KSP 1 where we can mount these engines without that large engine plate-looking structure?

Nice! You should try bringing up some Soyuz boats and doing some flyarounds to show all the angles of the station off.

I fly tilted spacecraft all the time! Or was it that I fly spacecraft while tilted? hmm...

I think the number of notches on the flight UI we've been shown imply we get at least an order of magnitude better than KSP maximum, i.e. a million times normal speed. We may even get another on top of that - so 10 million times normal speed.

So, I don't know if this footage has been available elsewhere but one of ShadowZone's recent videos has actually shown example Daedalus craft XYZ departing its orbital shipyard in a recent video. At about 9:23: That is a RIDICULOUS amount of acceleration if we're going to be burning for months or years. That was like, somewhere between 0.1 G and 1G. Which is nuts. If you ask me, it implies that although the Kerbol system itself is at a miniature toy scale then it seems that the distances in the local stellar neighborhood won't be. If anything, it almost implies that the planets you'll find out there will be more like the real life solar system in size. Is this a crazy guess? Maybe! That's still crazy acceleration if you ask me.