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ferram4

[0.90]NEAR: A Simpler Aerodynamics Model v1.3.1 12/16/14

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Is it intended bahaviour that TurboJet Engine is 110 thrust and basic jet engine is 150 ? I can't get any plane with Turbo Jet off the ground with NEAR. The ratio of mass and consumption vs thrust is ridiculous.

It's intentional but if you don't like it, it's easy enough to undo. It's a patch installed in the NEAR.cfg file that sets all air breathing engines maxThrust to 1/2 power. Comment it out or delete it (EDIT: Don't delete the whole file, just the one @PART section that changes it). In my case I kinda liked the idea, but felt it was too heavy handed so I changed it from 0.5 to 0.75. For me it feels more balanced now but that's really a personal taste thing.

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@Dre4dW0rm: Yes, that is intentional. They are about as powerful as real jets (without the reduction in thrust with altitude), have the mass of real jets, and are still far more fuel efficient than their real life counterparts. Fuel consumption per unit thrust has not changed with NEAR, so I don't know what you're talking about with respect to fuel consumption being wrong. If you can't get a plane off the ground, then I'm going to take a wild guess and say that your planes are way too heavy; even so, you should have no difficulty reaching a (relatively high) take off velocity of 100 m/s by about 3/4 of the way down the runway with normal-sized vehicles.

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@Dre4dW0rm: Yes, that is intentional. They are about as powerful as real jets (without the reduction in thrust with altitude), have the mass of real jets, and are still far more fuel efficient than their real life counterparts. Fuel consumption per unit thrust has not changed with NEAR, so I don't know what you're talking about with respect to fuel consumption being wrong. If you can't get a plane off the ground, then I'm going to take a wild guess and say that your planes are way too heavy; even so, you should have no difficulty reaching a (relatively high) take off velocity of 100 m/s by about 3/4 of the way down the runway with normal-sized vehicles.

Thanks.

I have stock 0.24.2 with B9_Aerospace v5 and NEAR latest.

I tried a B9 mK2 cockpit + single fuselage with liquid fuel + split engine tail + long delta winglets with control surfaces set to pitch/roll + 2x turbo jet engines 110? each and 2 B9 small intakes. I can reach 190 m/s on the ground but just can't take off. Maybe it's something with the wings. I'll try some other configurations.

It's intentional but if you don't like it, it's easy enough to undo. It's a patch installed in the NEAR.cfg file that sets all air breathing engines maxThrust to 1/2 power. Comment it out or delete it (EDIT: Don't delete the whole file, just the one @PART section that changes it). In my case I kinda liked the idea, but felt it was too heavy handed so I changed it from 0.5 to 0.75. For me it feels more balanced now but that's really a personal taste thing.

Thanks, will try this too.

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Also, what's your TWR? Very high TWRs encourage rockets to lose control and become unstable.
It was around 1.40, definitely not too high.
I'm curious though, considering that ascent profiles are heavily affected by aerodynamic forces, did you not think that changing aerodynamics would require changes to your flight profile?
I expected to be able to touch the controls. I didn't suddenly turn to 45 degrees, that's not how a gravity turn works, I don't do that in stock KSP either. I literally touched the D key (heh, touched the D... sorry) and the rocket spun out.

Anyways, I just thought I'd share my experience in a somewhat humorous way, I never had a problem with stock "Aerodynamics", just thought I'd give Ferram a go, it ended poorly.

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At what speed and altitude and *current* TWR did you do that? How much control authority did you have at the time?

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So...when should I make my gravity turn ? (sorry its the first time I go into aerodynamics mods)

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So...when should I make my gravity turn ? (sorry its the first time I go into aerodynamics mods)

I'm a bit new at this but the answer seems to be different for every rocket, but in general you want to turn some time in the first 100 m/s.

I have a fairly uncontrollable rocket that does a perfect gravity turn if I tip it 5-10 degrees at about 30-35m/s. If I do it at 20m/s, the rocket ends up peaking at about 20km and then falling into the ocean. If I wait until 50m/s it essentially goes straight up until about 35km and by then it's not a gravity turn so much as a big huge fuel wasting endeavor.

I found out where the correct place was by testing. And by testing I mean wasting a TON of funds because I refused to revert to launch or the hangar :D

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Want a better aerodynamics model, but think that FAR is too much?

Dislike having to deal with Mach number effects, strange wing interactions and aerodynamic dis-assemblies?

Ain't got time for aerodynamic analysis, just got time to build and fly?

Then you should try:

Neophyte's Elementary Aerodynamics Replacement

A simpler aerodynamics model

Features:

What it does that is similar to FAR:

--Drag is based on shape and orientation

--Body lift from parts

--Infiniglide wings are gone, and now follow a velocity2 proportionality like they should.

--Payload fairings and cargo bays function properly

--Vehicle stability does need to be considered when building rockets and planes

What it doesn't do, that FAR does:

--Changes in physics with Mach number

--Complicated changes in wing lift and drag due to other parts around them

--Aerodynamic dis-assembly (though they can still be broken off if they overload the stock joints)

--Complicated aerodynamic analysis tools in the editor

This mod is intended as a simpler aerodynamics model for people who want to get into FAR but are discouraged by the learning curve or for users that aren't interested in all that FAR has. It is built on the same code as FAR, and so any mods that are compatible with FAR should be compatible with NEAR.

As with FAR, licensed GPL v3.

FAQ

I'm getting a lot of lag / my vehicle performance seems weird. What gives?

This sounds like a craft file from before 0.24, primarily affecting previous users of FAR. Due to changes in 0.24 to make contracts function, some PartModule-related issues can occur with saved crafts. There is a method to recover such crafts, with directions here. Newly created crafts should be unaffected.

Not that i dont like (love) your work in general Ferram, but why not make FAR have options so that players can tweak how realistic they want it to be (i actually think all plugins should allow you to turn them on or off so that we dont have to uninstall if we dont want it running). I'm pretty sure you can already turn aerodynamic dis-assembly off, why not add further "realism" options that allow players to decide if they want lift/drag to be a function of mach number (thereby approaching NEAR), and maybe even an option to make it not a function of AoA either and/or shape but rather, just mass (to approach stock). I'm sure you could add many more detailed options, and probably also groups to allow users to select "easy" "medium" or "hard" mode, which correspond to different sets of options being on or off. An added advantage is intrinsic compatibility (mods that work with FAR dont always work with NEAR since sometimes it looks for files/configs with the word "FAR" in it; doing this would avoid that problem).

What do you think?

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Is it intended that you go up to almost 470.000 km from the launchpad with the standard start rocket (1 Short Solid Fuel Booster, Command Capsule, Parachute)?

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Is there something wrong with my install? I get to almost 470 km with the standard start rocket (1 Short Solid Fuel Booster, Command Capsule, Parachute) from the launchpad.

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Is there something wrong with my install? I get to almost 470 km with the standard start rocket (1 Short Solid Fuel Booster, Command Capsule, Parachute) from the launchpad.

As I understand it, aerodynamic rockets will encounter much less resistance under this model than stock. In any case, if your 'rocket' is mostly propellant then I'd expect you to get quite a long ways no?

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@Dre4dW0rm: You're reaching nearly 2.5 times the average take off velocity for jets without getting airborne. At that point, your problem is not thrust, it's lack of lift. You're either going to want to look at adding more wing area / reducing mass if you're capable of rotating properly, and look into placing the landing gear further forward if you're incapable of rotating for take off.

@BadManiac: If your rocket immediately lost control after slightly touching the controls, that means that it was barely stable and that you had too much control authority. That said, I'll admit that I don't quite believe you; a rocket that unstable would have flipped long before attempting the gravity turn unless it was completely dependent on SAS to maintain control.

@arkie87: I think you are underestimating the interconnectedness of aerodynamic phenomena. Removing stuff from FAR in a way that didn't make things horribly unstable for NEAR was a challenge in itself, and even then, NEAR still has a lot of places where you can end up with unstable and nasty things that FAR doesn't have because removing proper aerodynamic effects causes weird things to happen. If I left all those options in I'd be inundated with people complaining that their rockets / planes were unstable when they disabled something that would have aided in making them stable.

It would be great if all my users were aeronautical engineers and I could do that. As it stands though, they aren't, so I can't. It's not like people ever touch the options anyway, people always say they're dropping FAR because of the aerodynamic failures despite the fact that I added an option to get rid of them.

@MunarJetman: It takes ~1000 m/s of dV to get up to an altitude of 100 km based on gravity alone. You launched a rocket with 2.3 km/s of dV. Drag is not a force that is equal to gravity by any stretch of the imagination, so that result kinda makes sense.

Same thing happens if you launch a rocket with that much dV on Earth too.

Edited by ferram4

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Alright. Thanks for the answer! I will try some more things and get used to the mod hopefully.

Also, sorry for the double-post. I'm not used to forums where you require moderator authentication for your posts to show up.

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As a way to deal with spam (which we do get a lot of--if you don't see it, that just means we're quick at dealing with it ^_^ ) a user's first five posts are moderated. After that, free and clear.

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@arkie87: I think you are underestimating the interconnectedness of aerodynamic phenomena. Removing stuff from FAR in a way that didn't make things horribly unstable for NEAR was a challenge in itself, and even then, NEAR still has a lot of places where you can end up with unstable and nasty things that FAR doesn't have because removing proper aerodynamic effects causes weird things to happen. If I left all those options in I'd be inundated with people complaining that their rockets / planes were unstable when they disabled something that would have aided in making them stable.

It would be great if all my users were aeronautical engineers and I could do that. As it stands though, they aren't, so I can't. It's not like people ever touch the options anyway, people always say they're dropping FAR because of the aerodynamic failures despite the fact that I added an option to get rid of them.

I see. You might not be able to give options to disable each individual effect, because it might lead (incorrectly) to instability and cause an inundation of complaints. But what about adding an option to switch groups of options that maintain stability, or, at the very least, make FAR essentially become NEAR?

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@ferram4 I love this idea. I have used FAR since its early days but I am not a "planes person." I just wanted more realistic gravity turns for my rocket launches. However, MaxQ is a cool stat to see and know for a rocket guy like me. It appears there's no way for me to see it in NEAR? I will have to switch back to FAR if there is absolutely NO user interface for cool stat displays like terminal velocity, MaxQ, etc.

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One of the biggest complaints about FAR was that it had a GUI. So NEAR does not have a GUI because that was one of the things requested by users when I was looking for feedback on a simpler aerodynamic model.

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@Dre4dW0rm: Yes, that is intentional. They are about as powerful as real jets (without the reduction in thrust with altitude), have the mass of real jets, and are still far more fuel efficient than their real life counterparts. Fuel consumption per unit thrust has not changed with NEAR, so I don't know what you're talking about with respect to fuel consumption being wrong. If you can't get a plane off the ground, then I'm going to take a wild guess and say that your planes are way too heavy; even so, you should have no difficulty reaching a (relatively high) take off velocity of 100 m/s by about 3/4 of the way down the runway with normal-sized vehicles.

Not only are they more efficient than a real jet engine. They are more mass efficient than any possible chemically-powered engine. Unless AJE and real fuels are installed, jets in KSP have impossible efficiency. The ISP calculations are as if the exhaust air is moving out the back at the velocity one would expect for a chemical rocket, and not a turbojet, where the maximum exhaust velocity should be ~2300 m/s (ideal).

Plus, if you are installing real fuels and AJE and such, FAR would be the proper aerodynamics mod to use.

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I have a small question. In the flap configuration menu (right-click) there is one option that is cut off that says "Use as spo...". What does that mean?

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I have a small question. In the flap configuration menu (right-click) there is one option that is cut off that says "Use as spo...". What does that mean?

That means that the control surface will be used as a spoiler and will deflect up when you activate the breaks.

It's often used to drop lift and increase drag on landings.

So, a good thing to do is to use flaps and spoilers, you increase lift with flaps then drop it with spoilers and gain even more drag.

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This is an excellent mod...especially for my kids. I appreciate your stand on the GUI for this, the one for FAR can be a bit confusing. What I would like to recommend is to put a GUI back in the game for NEAR. However this time make it display only basic information about the craft. This way people can start to get a better understanding of what the plane/rocket is going to do and the best way to approach correcting the issue. Something like...flaps, show the min/max it can go with the current craft before you deviate, then show where the persons craft is rated on that scale...dont tell them how to fix it though. This is where the trial/error comes in.

Still love the mod, and will be using it for all "stock" installs from here on out.

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The is no way to dumb down the GUI like that without also making it completely wrong in enough cases to make it worse than having no GUI. There are no easy ways to rate aircraft like that. There is no way to measure anything about flap performance without going into FAR's level of GUIs.

NEAR will never have GUIs, and that is final. You wanted simpler, you get simpler.

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Does it have cheats like far does?

If there is no GUI where you would activate cheats there are no cheats (or are there?).

What would you cheat anyway?

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