Alternatives to Ferram for realistic drag models?

[Proply]

Hi, I was just wondering if anyone knows of any mods that change the drag model so that it is not linked to part mass, but isn't FAR. My reason for this is that I want a mod that makes nose-cones, fairings, etc, necessary for efficient launches, but I find that FAR makes getting to space too easy - I did a test with a small solid booster without a nose-cone in both stock KSP and with FAR and found that it actually went 4km higher with FAR installed, and that is without a nose-cone! With a nose cone FAR just makes it too easy! So if anyone knows of a mod that alters the drag model to be more realistic, but still maintains a similar level of difficulty to stock KSP (for example, worse performance than stock without nose-cone, and similar or slightly better performance than stock with nose-cone), a link would be much appreciated!

-Thanks, Proply.

[EDIT] While no other mods such as I described exist at present, Ferram has made the Kerbal Isp Difficulty Scaler which addresses my concerns. Thanks Ferram!

Edited October 16, 2013 by Proply

[Diazo]

Umm, to me that means FAR is working?

In the default model, each model's drag value is simply added up to get the vessel's drag (I believe). This is why nosecones are always a bad idea stock.

With FAR, even a short rocket, only the top fuel tank is producing drag, the other tanks (if present) and the engine are in line behind that first fuel tank and produce no drag.

Perhaps a picture?

As for other mods that modify the aerodynamic model, I am not aware of any.

D.

[Hodo]

I have never heard FAR makes getting to space too easy. But there are no others that I am aware of either.

[Eric S]

FAR attempts a more realistic atmospheric model, rather than just a more realistic drag model balanced for gameplay against the current drag model.

In reality, drag losses are about an order of magnitude less than we see in typical KSP launches, so of course a realistic mod is going to make it easier to get into space. I think the atmospheric drag losses on the Apollo missions were on the order of 80 delta-v, and most other launch systems were under 200 delta-v.

Deadly Reentry ran into similar issues. There's just not as much reentry heat possible in KSP as in reality because our reentry velocities tend to be significantly lower than reality. As soon as they went with a reentry heat model that was realistic, they had to look for things other than heat to make reentry deadly.

[NathanKell]

If you want things to be hard, just decrease engine thrust and Isp. The Isp is way too high anyway for non-hydrolox rockets.

[m4v]

IMO, FAR shouldn't neglect the gameplay aspect of the game: making something realistic, with the consequence of making it easier, is counter intuitive and not something you seek when looking for realism.

[NathanKell]

Then why are half the posts in the FAR thread people complaining about it making the game too hard?

[Diazo]

One thing to keep in mind is that FAR is really about planes, not as much the rockets.

It implements an aerodynamics model that is closer to reality so planes work more like we expect them too in a mod.

That then carries over to our rockets.

Besides, I would think any mod that affects aerodynamics would have reduced drag, I can't think of any model that is worse then the current one of each part adding a fixed sum to the drag equation.

To be clear, in base KSP, two fuel tanks have twice as much drag as one, placement does not matter. Stacked/split/horizontal/vertical/etc.

Now FAR comes along, and placement matters. Of course two fuel tanks stacked vertically are going to have a lot less drag then two fuel tanks placed side by side.

Regardless, it is a mod. Play around with it and leave it enabled or not.

D.

[Nobody_1707]

IMO, FAR shouldn't neglect the gameplay aspect of the game: making something realistic, with the consequence of making it easier, is counter intuitive and not something you seek when looking for realism.

What? That is what one is generally seeking when one looks for realism. Perhaps you're thinking of verisimilitude?

[Van Disaster]

It's not FAR making it easier, it's the stock engines being overpowered ( and thus making it easier ). FAR only makes simple rockets easy anyway.

Making something arbitrarily artificially hard is ludicrous, might as well forget any ideas about physics & simulation at that point.

[NathanKell]

Further, let's all recall that LKO takes less than half the deltaV required for low earth orbit. If you want to complain about people making it too easy, talk to Squad.

(And deltaV is exponential when it comes to fuel mass: double the deltaV, way more than double the fuel/thrust; half the deltaV, way less than half the mass of booster required.)

[Van Disaster]

What would also help is if ISP worked properly, so thrust changed with the atmosphere instead of fuel consumption; starting your giant rocket off when it's engines aren't able to provide full thrust *and* it has to be a sensible aerodynamic shape is starting to get interesting. I know there's a mod around that corrects ISP for some engines, but as it doesn't work with multi-mode things like B9 Sabres I've not actually tried it.

[m4v]

stock engines being overpowered

which engines? jet or rocket ones? you can argue that turbojets are OP, but rockets? they are pretty underpowered compared with IRL. Edited October 15, 2013 by m4v

[Read have Read]

Ah, the SRB test. A single part with very high TWR, lots of fuel, no payload and very little extra mass is not exactly indicative of what you will see from actual launches in FAR. While it is true that you can shave off 1000 Delta-v to orbit, the difficulty comes back in actually flying the rocket. With actual Aerodynamics, the direction of travel into the wind or through the air is very important - Planes and rockets alike can and will stall, spin and break up due to aerodynamic stresses caused by high Angles of Attack. I have many launches fail during MaxQ as side forces flipped my rocket around and I did not go to space. Mechjeb is has a hard time of launching a rocket in FAR. An asscent requires careful and gradual gravity turns starting right as you leave the pad and ending as you reach 35km, where atmospheric pressure drops to 0.001 or less.

[rhoark]

Learn to stop worrying and love the FAR.

[NathanKell]

Van Disaster, MFS does that now, and it works on anything configured for MFS, including B9 engines.

[Sean Mirrsen]

The thing about FAR is that it's not balanced against the rest of the game.

What I'd like to see is a version of FAR with variables tweaked so that a typical well-built stock rocket takes as much effort to get into space as it does in unmodded KSP. Take... I don't know, Kerbal X. Or really, any simple orbiter, built with aerodynamics in mind (i.e. with nosecones and such), and see how much delta-V it expends getting to orbit - then take FAR, and tweak it so that the same orbiter takes as much delta-V to get into orbit.

When balancing, it is important to find something to balance against. Balancing against the real world, when you have a planet with the same surface pressure and gravity, but ten times less size and atmosphere than Earth, is just not going to work. The point of FAR is to make design matter and add realism to aerodynamics - not make the game easier by any stretch. But in doing what it does it makes rockets stupidly overpowered. Tuning the rockets down is not a solution - they are balanced against the masses they must lift, for vacuum as well as atmosphere. The solution is to tweak FAR in such a way that it makes a well-built stock rocket rise to space as easily as it does in stock KSP, and make worse designs perform worse - not the other way around.

[HeadHunter67]

If that's what you want, why use FAR at all?

[NathanKell]

Again, take it up with Squad. It's their low planet size that makes things easy.

Besides, the same low drag that makes ascent easier (for certain values of easier) makes reentry harder (for _any_ value of harder). Assuming you're using Deadly Reentry, which if you care about difficulty as much as you say, you should.

[ferram4]

I'll admit that this issue has always irritated me a bit--realism shouldn't necessarily mean "easier," but given that the stock atmospheric model results in Kerbin being surrounded by some kind of pudding-like gunk, it's somewhat inevitable. To try and somewhat counteract this, I went and developed the new Kerbal Isp Difficulty Scaler plugin to reduce Isps and try to help rebalance KSP with FAR installed. I normally shy away from such obvious self-promotion, but considering this is the very reason why I developed it in the first place, I figured you guys would like to know about it.

[NathanKell]

As I said there. HAHAHA. Nice.

[enki]

I like the changes FAR adds to make spaceplanes sensible. I'd be willing to settle for a FAR-lite that includes control surface assignments, but getting a rocket to orbit stopped being a challenge for me a LONG time ago. Yes it requires less dV for orbit, it makes my rocket handle more like a rocket should. Changing pitch isn't something that you just do more or less instantly with little regard to your velocity vector. FAR fixes the infiniglider glitch (mostly, I was still able to get a plane to inch along with control surfaces, it didn't go up, it didn't reach orbital velocity) and generally makes planes tolerable to fly. I don't want to go for ultra realism. If anyone has been following Feed The Beast lately the patches that 'increase difficulty' only end up in adding tedium, not fun. FAR adds fun.

[Proply]

I'll admit that this issue has always irritated me a bit--realism shouldn't necessarily mean "easier," but given that the stock atmospheric model results in Kerbin being surrounded by some kind of pudding-like gunk, it's somewhat inevitable. To try and somewhat counteract this, I went and developed the new Kerbal Isp Difficulty Scaler plugin to reduce Isps and try to help rebalance KSP with FAR installed. I normally shy away from such obvious self-promotion, but considering this is the very reason why I developed it in the first place, I figured you guys would like to know about it.

Awesome, thanks! I will update my original post to list this solution.

[Sean Mirrsen]

If that's what you want, why use FAR at all?

Because I like it when design matters, plus I like FAR's control surface settings.

I want FAR to be balanced against the game, picking a definite standard for performance and tweaking it from there.

Hmm, I wonder. I do have some programming skill, maybe I could get permission and make a modified FAR version?

Call it NEAR or something.

[HeadHunter67]

Because I like it when design matters, plus I like FAR's control surface settings.

I want FAR to be balanced against the game, picking a definite standard for performance and tweaking it from there.

But you just argued that you want a craft with FAR to perform exactly the same as one without. So what's the point?

You clearly don't want it to change a craft's aerodynamic performance... unless you meant something different, in which case you might have spoken about that instead of going on about something else entirely.