Does the Community Want Better Aerodynamics?

[Eric S]

Yes. Not only proc fairings but also various cargo holds (like B9 and Nothke service compartment). Anything under a fairing or inside a cargo hold does not produce drag at all.

Provided that FAR recognizes the part as shielding the contents. That's not a given, and since FAR doesn't try to simulate the craft's airflow it has to be recognized in order to work. In fact, originally FAR didn't recognize procedural fairings. I don't remember which was changed to fix that. I think the same thing happened to the 6S parts.

[Roman_legion]

Sure better aerodynamics. But forcing players into proper reentry angles doesnt feel kerbal.

[Vrana]

Provided that FAR recognizes the part as shielding the contents. That's not a given....

True, but the recognition already works on every mod i can think of and if it doesnt its a trivial matter of renaming the unrecognized part since FAR detects fairing/cargo according to part name.

[Eric S]

True, but the recognition already works on every mod i can think of and if it doesnt its a trivial matter of renaming the unrecognized part since FAR detects fairing/cargo according to part name.

Which doesn't change what I said. I was clarifying the statement that "Anything under a fairing or inside a cargo hold does not produce drag." The actual statement should be "Anything under a fairing or inside a cargo hold that FAR recognizes as such does not produce drag." and there have been enough (usually temporary) exceptions to that to note the condition, including the entire category of fairings made out of structural panels.

[TMS]

...and there have been enough (usually temporary) exceptions to that to note the condition, including the entire category of fairings made out of structural panels.

That's because they're not fairings, they're structural panels.

[Eric S]

That's because they're not fairings, they're structural panels.

... that when arranged in the right way, get called "stock fairings" by some people. It might make the craft look more aerodynamic, but they're not functionally fairings. On that we agree, I'm just making sure that people understand that FAR does not simulate air flow, so just because it looks like a fairing doesn't mean it will function like one.

[Leatherneck]

I showed this before with albums even but you and the rest of the naysaying minortiy outright ignored it. Lets try again....

YOU CAN LAUNCH INASNE ROCKETS WITHOUT FAIRINGS WITH FAR INSTALLED. You are afraid of something that does not exist (at least in current FAR).

Just takes more dV and possibly a better understanding of how to lift it. But in no shape or form are you losing game options by installing FAR(other then outright exploits like infigliding if that is still psosible in stock).

Of course they're going to ignore your post, it's far easier to ignore it than address it with a valid counterpoint.

[Madrias]

I may have been unfairly biased against FAR. I figured, seeing as the last time I'd used it was back in .20, I'd give it another try. And it's not too bad. I can make it off the runway and I can cruise around. That's good enough for me at this point, and I can still build somewhat Kerbal aircraft designs. If it ends up being the standard for aerodynamics, I can certainly adjust, though it'd take a bit of effort.

[Azimech]

Airflow simulation is the Holy Grail of aircraft simulation. This is what X-Plane does and so even aircraft designers use it (because you can design planes in X-Plane, really cool and really hard!)

It works for a relatively simple body like an airplane. It would work for KSP, if only we all had supercomputers. But hey, if it ever appears (maybe "KSP, The Next Generation"?), we can even build working fairings out of structural plates.

[TMS]

... that when arranged in the right way, get called "stock fairings" by some people. It might make the craft look more aerodynamic, but they're not functionally fairings. On that we agree, I'm just making sure that people understand that FAR does not simulate air flow, so just because it looks like a fairing doesn't mean it will function like one.

Understood.

I suspect accurate air flow might turn our designated, solitary-confined, KSP processor into a gibbering wreck.

[Gweese_king]

I think if there is a way to make flight cheracteristics more realistic across the board it should be implemented. I would like to see deadly results from poor reentry angles as well. I think a major draw to ksp for me was that it offered an educational challenge that few games can replicate. You have to learn to play the game, its great. On that note, I say make it harder, bring on the challenge. This community wouldnt exist if the game wasnt challenging people to the point of having to research and discuss with other players. I think more accurate aerodynamics would be a welcome addition to the game. But it would have to come with some new stock parts (fairings of all sizes and shapes). If you cant launch your rediculously shaped rocket all at once, assemble the damn thing in orbit with multiple launches and dockings. It adds to the challenge.

[Execute13]

That's like saying stock is pea soup versus FAR's chicken broth, when FAR is actually more tomato-soupy. But I can see how it was read that way.

Sorry for bringing up a post several pages back, but so much funny!

On Topic: I feel that better aerodynamics, though not as important at this stage in development, aren't really that hard to implement because it's already been done, and the resources are out there. I don't think that FAR should simply be added into the game as-is, but I think that the fact that planes are impossible to stall, given enough wings, needs fixing. Yes, this is Kerbal Space Program, but don't forget that there is a runway.

[Nao]

I think if there is a way to make flight cheracteristics more realistic across the board it should be implemented. I would like to see deadly results from poor reentry angles as well. I think a major draw to ksp for me was that it offered an educational challenge that few games can replicate. You have to learn to play the game, its great. On that note, I say make it harder, bring on the challenge. This community wouldnt exist if the game wasnt challenging people to the point of having to research and discuss with other players. I think more accurate aerodynamics would be a welcome addition to the game. But it would have to come with some new stock parts (fairings of all sizes and shapes). If you cant launch your rediculously shaped rocket all at once, assemble the damn thing in orbit with multiple launches and dockings. It adds to the challenge.

And yet here are a lot of people who can only get to Mun with Mechjeb, and are having great fun. Hard is good, but the Formula for good game is "easy to learn hard to master" So it's either some compromise to make things manageable for everyone or having an option to select simulation accuracy. (but that begs for more changes in other parts of the game as well, so not going to happen soon)

Airflow simulation is the Holy Grail of aircraft simulation. This is what X-Plane does and so even aircraft designers use it (because you can design planes in X-Plane, really cool and really hard!)

It works for a relatively simple body like an airplane. It would work for KSP, if only we all had supercomputers. But hey, if it ever appears (maybe "KSP, The Next Generation"?), we can even build working fairings out of structural plates.

There are two notable problems with accurate airflow simulation. 1) Real time computing of advanced flight model it would require pre-computing the flight characteristics of a plane. Since KSP planes can have many parts, it would be almost impossible to do, as there is to much configurations for one plane. And computing things as the situation changes is out of the questions on PC's for probably maaany more years.

2) Most KSP part's and general rocket shape resulting from them is quite suboptimal (simplified shapes, lack of many transition parts etc). That could cause lots of problems, forcing implementation of internal "fly be wire" system to have somewhat predictable and consistent controls, and that has its own can of problems.

For example currently wings are just boards with sharp edges. Without preset properties for each part they wouldn't work as good wings at all, and then if they had one, interaction with other parts like more wings around or other parts placed on wing would be almost impossible to predict and include in the parametrers.

This is why only simplified modes will work, and Ferram has made excelent work creating one. But I think before it can be implemented it would need some tweaking to balance characteristics for both untrained pilots, and game veterans.

Actually i think a Ferram model + some sliders for adding simplifying counter-forces forces that would help getting predictable and forgiving flight characteristics would be the way to go (default: on, with some information popup, like the one for physics acceleration).

[Mmmmyum]

And even if doing airflow calculations would add to the workload our CPU's have to do, they could easily run it on another core

Edited December 22, 2013 by Mmmmyum

[FenrirWolf]

I showed this before with albums even but you and the rest of the naysaying minortiy outright ignored it. Lets try again....

YOU CAN LAUNCH INASNE ROCKETS WITHOUT FAIRINGS WITH FAR INSTALLED. You are afraid of something that does not exist (at least in current FAR).

Just takes more dV and possibly a better understanding of how to lift it. But in no shape or form are you losing game options by installing FAR(other then outright exploits like infigliding if that is still psosible in stock).

When I first installed FAR this was my worry too. I thought that if the aerodynamics were more realistic then it meant that all my rockets had to be boring tall things. But that really isn't the case. Heck, considering FAR makes it take 1000 less delta-v to achieve orbit, that just means you can throw that extra delta-v towards forcing more contrived contraptions into space whether they like it or not!

Besides, don't we remember why we are here to begin with? KSP is a spaceship game that doesn't insult our intelligence and isn't afraid to throw some real-world physics in our face. Of course we know that it doesn't throw all the physics at us, since we're dealing with patched conics instead of relativistic physics. But the system the game presents does strike a wonderful compromise between realism and playability. Whatever SQUAD decides to implement when it comes to aerodynamics doesn't have to be exactly like FAR, but I feel like FAR itself does a pretty good job of being a decent approximation to reality while being a fun environment at the same time.

Edited December 22, 2013 by FenrirWolf

[Nao]

And even if doing airflow calculations would add to the workload our CPU's have to do, they could easily run it on another core

Having meaningful CFD computation requires tons of power. Maybe supercomputer could run simple simulations in real time. And simplified models like the ones used in flight sims use a lot of precomputed parameters. In KPS the problem would occur when the ship itself changes, for example during staging, as it would freeze the game for a moment to create new model for each part even if this was done on the other seven cores.

I don't have much knowledge on modern flightsim physics models so there might be tricks that could be used to bypass these problems, but i'm sure it wouldn't be easy to implement in KSP, and even harder to put in a thread separated from main physics thread.

[Mmmmyum]

Having meaningful CFD computation requires tons of power. Maybe supercomputer could run simple simulations in real time. And simplified models like the ones used in flight sims use a lot of precomputed parameters. In KPS the problem would occur when the ship itself changes, for example during staging, as it would freeze the game for a moment to create new model for each part even if this was done on the other seven cores.

I don't have much knowledge on modern flightsim physics models so there might be tricks that could be used to bypass these problems, but i'm sure it wouldn't be easy to implement in KSP, and even harder to put in a thread separated from main physics thread.

Surely it could be a requirement that all parts (mods etc) have a precomputed airflow model? That would take nearly all the load off our PCs. And make it as simple as possible while being realistic as possible

[Eric S]

Surely it could be a requirement that all parts (mods etc) have a precomputed airflow model? That would take nearly all the load off our PCs. And make it as simple as possible while being realistic as possible

The airflow around any given part is going to depend on any other parts in the vicinity of that part, the direction of the airflow, the speed of the airflow, etc. While you might be able to factor away the latter components, you can't precompute the first one since there's no way to precompute it prior to the craft being built in the VAB. Think about it, the whole point of a nosecone is to reduce the drag of the craft, which means that it's going to affect the airflow of anything under it, assuming it's pointed into the airflow. If the craft is going sideways, it shouldn't help the other parts, and will only be adding drag to the craft.

[Skyrunner27]

I don't think an option should be made. A game is a player doing things with a certain amount of restraints. Also FAR as I have seen it will not effect large rockets(I am just going off of others who use FAR). The current aerodynamics model is holding the community down. While doing nothing to lift the community up. I would take it as far as to add damaging reentry effects because right now it is too easy to just recover science experiments. Also reentry has became boring about 3 weeks after .19 dropped.

[Nao]

Surely it could be a requirement that all parts (mods etc) have a precomputed airflow model? That would take nearly all the load off our PCs. And make it as simple as possible while being realistic as possible

The problem is that while one wing has a set of properties, if we add several wings together just adding their values won't create realistic properties for the construction. Real life example of that are multi-wing aircraft, just as we saw in aircraft development in first world war, they were adding more wings on top of each other to increase lift, and there were severe diminishing returns from each one added. In the end we ended up with one wing as the most best option.

This means we need new base properties model for each plane configuration. Modern simulators have limited module count that allow every part to be computed for limited set of flight states it can get itself into. In KSP we can have 200 wing plane hit the launch tower and disassemble almost randomly, only the simplest flight models can compute flight properties on the fly for each separated element.

...argh didn't see Eric answering that one >_< , aw whatever posting my answer as well away ~weee

[Eric S]

...argh didn't see Eric answering that one >_< , aw whatever posting my answer as well away ~weee

Yes, but I liked your answer better, the real world implications of multiple wings is fascinating stuff. I always thought that the reason multiple levels of wings went away was because faster craft produced more lift, so less wing was needed. However, if that were the reasoning, they would have kept the multiple wings and just gone with shorter wings because they'd be more structurally stable. See, you really can learn something new every day.

[Nao]

Yes, but I liked your answer better, the real world implications of multiple wings is fascinating stuff. I always thought that the reason multiple levels of wings went away was because faster craft produced more lift, so less wing was needed. However, if that were the reasoning, they would have kept the multiple wings and just gone with shorter wings because they'd be more structurally stable. See, you really can learn something new every day.

The two main problems of multiple wings are simple: 1) As the wings work on pressure (top of the wing having less pressure than bottom) another wing right above the first one will cancel the effect out (thats why on modern 2 wing aircraft like acrobatic Pitts top wing is placed more forward) and 2) Up to 40% of wing drag comes from induced drag that forms at the wingtips, more wingtips more drag, thats also why gliders have very long wings and many modern planes have winglets.

Edited December 23, 2013 by Nao

[vexx32]

Actually, Nao, that's a common misconception. A pressure difference is not in fact what causes lift. It's commonly taught, but it's incorrect -- go on, look it up. I had to, after making the same mistake many times. Lift is created because the curved upper surface deflects air downwards, and by the Second Law of Motion, that results in an upward force on the wing. It works because air clings to the surface of the wing, a bit of an odd quirk of fluid dynamics.

If they did work on pressure difference, stunt planes wouldn't work, since both lower and upper wing surfaces have the same curved surface (so that the plane can fly just as well upside down).

[Leatherneck]

Actually, Nao, that's a common misconception. A pressure difference is not in fact what causes lift. It's commonly taught, but it's incorrect -- go on, look it up.

Okay, where's the source on that? Your description goes directly against Bernoulli's principle, or you are also describing it incorrectly.

The air going over the top of the wing (standard shape) has to move faster than the bottom, which causes lower pressure on the top, and the higher pressure air underneath pushes the wing up. It has nothing to do with air being pushed down. This is why you can stall an aircraft from too steep of an angle of attack, because the air flow "breaks" and you get a dead zone which breaks up the effect. Flaps (back of wing) and Slats (front of wing) will affect the shape of the wing to alter for changes in airspeed and the desire for more/less lift, but the principle remains the same.

Edited December 24, 2013 by Leatherneck

[allmhuran]

For the "classic" airfoil shape both principles are in effect. Planes flying upside down have to counteract the pressure difference by increasing AoA, and thereby increasing deflection at the cost of airspeed.

Edited December 24, 2013 by allmhuran