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

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Odds are that it's plane design, not the mod being wrong. It is almost always plane design. Of course, the exact cause is basically impossible to determine without a picture of the plane, the velocities that you're flying at at each altitude, and how the CoM moves as fuel burns. It could also just be running out of air for the engines leading to uneven thrust causing a spin.

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Is NEAR the reason most of my spaceplanes fly AMAZINGLY smooth and well, but above a certain altitude, they become completely uncontrollable and flat spin or roll out of control or both? Or is this related to my plane design?

Most likely caused by a flameout. If you have more than one air breathing engine that are offset from the center of mass and one flames out while the other doesn't you will have asymmetrical force. That will ruin your day quickly. There are a few ways to get around this.

1. Use only one engine, not the greatest solution if you need more thrust.

2. Use an action group to shutdown the engines before they flame out.

3. Angle the engines so their center of lift is inline with the center of mass. This takes some creativity, but can work.

But this is just a guess, as stated we need a picture and more info as other things could cause it to occur as well.

Make sure you have a screenshot with the CoM/CoL/CoT markers turned on.

Edited by Alshain

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Most likely caused by a flameout. If you have more than one air breathing engine that are offset from the center of mass and one flames out while the other doesn't you will have asymmetrical force. That will ruin your day quickly. There are a few ways to get around this.

1. Use only one engine, not the greatest solution if you need more thrust.

2. Use an action group to shutdown the engines before they flame out.

3. Angle the engines so their center of lift is inline with the center of mass. This takes some creativity, but can work.

But this is just a guess, as stated we need a picture and more info as other things could cause it to occur as well.

Make sure you have a screenshot with the CoM/CoL/CoT markers turned on.

I was using dual mode engines in rocket mode. CoT is in line with CoM which is forward of CoL by about 2 "marker ball lengths".

Best SS I have since made the changes to the CoM to CoL ratio as above and removed the "for looks" intake and engine mount on top between the tails, Also im flying with a joystick with the sensitivity set quite low if that helps but I can still barrell roll at about 180rpm. Havnt tried loops yet.

sGBcpPr.png

Edited by Nsomnia

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I was using dual mode engines in rocket mode. CoT is in line with CoM which is forward of CoL by about 2 "marker ball lengths".

Well there are several possible causes, that one is just the most common I see. Without a picture I can't pinpoint which one, so rather than stabbing at each of them, you should show it to us.

EDIT: Oh wait, CoL is IN FRONT of CoM? That's the problem. CoL needs to be just behind CoM for a stable aircraft.

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Well there are several possible causes, that one is just the most common I see. Without a picture I can't pinpoint which one, so rather than stabbing at each of them, you should show it to us.

EDIT: Oh wait, CoL is IN FRONT of CoM? That's the problem. CoL needs to be just behind CoM for a stable aircraft.

No the CoL is behind the CoM by about 1.5 ball marker lengths. See my picture above thats how it looked before my changes to make the CoL/CoM ratio more dart like.

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Well, I'm not the expert but from the picture above I don't think you have enough lift. The atmosphere gets thinner the higher you go so you get less lift which then results in a stall (I think that's the correct term, again not an expert), more speed can compensate for this, but I'm not sure something that heavy is getting that either.

Edited by Alshain

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I weighs 26t with 700kn of thrust. I was using Klockheed Martins Space Shuttle Engines with smooth slow gimballing if it helps.

Will try more thrust/engines later or bigger wings/some nice round wing tips and report back later if I still have problems.

Edit: Also if i stay below 10-12 km altitude i can get up to 3000 m/s if I remember correctly.

Edited by Nsomnia

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I would use bigger wings, those winglets are more designed for control, not lift. They do provide lift of course, but I don't think it is enough. The B9 wings can be pieced together. This is a plane I just re-designed using the new B9 pre 5.0. It flies... well decent but the high wings make it a little harder to maneuver. The key take away is just how much wing span it has, and this is the S2, your using a much bigger fuselage.

W0cALCj.png

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Nope im using the s2 exactly like your pic just with way less wing area and I assume less thrust. If I point straight up I can reach space.

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Nope im using the s2 exactly like your pic just with way less wing area and I assume less thrust. If I point straight up I can reach space.

My mistake, the tail confused me. I thought it was the HL. Off hand I don't know the exact thrust of that one, but you can probably add it up from the B9 turbojets. There are only 4. I think they got nerfed in the latest version as it doesn't fly quite as fast as it did in previous versions, but it still gets there.

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I have a suspicion. The inline decouplers near the nose! FAR/NEAR gives such parts with exposed top/bottom nodes huge drag. This could still cause some lateral instability (?? No expert here). It would be good to know if your problems persist if you remove them. And ofc also the radial attachment port.

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I have a suspicion. The inline decouplers near the nose! FAR/NEAR gives such parts with exposed top/bottom nodes huge drag. This could still cause some lateral instability (?? No expert here). It would be good to know if your problems persist if you remove them. And ofc also the radial attachment port.

All gone as I suspected those.

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I think if it flies fine at lower altitudes and then loses it high up, it's probably not drag.

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I added way more wing but it turns out that made it worse, now it glides all day long so i cant land it as i cant bleed off speed even with continual s turns 20km out from ksp runway. It still wants to glide back up. Turns out the engines were the problem. at 12000m the klockheed martin space shuttle engines throttled down and i couldnt throttle them back up. so I think if I tweak the wings some more and get rid of the 2500kn thrust monster central engine and stick with the 4 rapiers ill have me a nice space shuttle. I was origionally going to add the SRBs and LFO tank to make a real shuttle but this thing gets into orbit all on its own.

7cMaSyW.png

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noob question: does nose-cones and objects infront of the wing or area of lift affect the amount of drag, also can wingles objects like a fast moving fuel tank) provide a form of lift still

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Hey guys I have a question too, is this mod compatible with firespitter? I'm trying to use both but there are bugs, some control surfaces stop to work and =/

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@BLUESHADOW125: What do you mean specifically about the first question? There's no reason you should have a nose cone magically floating in front of a wing, so it won't have any affect on lift or drag (because it's not a realistic scenario at all). But for the second one, yes, a barn door moving fast enough will produce lift. Not much, but it should.

@Tigermisu: Firespitter should be compatible with FAR. If it is compatible with FAR, it should be compatible with NEAR unless the configs are not set up properly. If they aren't set up properly, that's in Snjo's domain, not mine.

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@Tigermisu: Firespitter should be compatible with FAR. If it is compatible with FAR, it should be compatible with NEAR unless the configs are not set up properly. If they aren't set up properly, that's in Snjo's domain, not mine.

There's one place in Firespitter's FSWingBase module that tests for FAR by name. Snjo may need to update that to also test for NEAR.

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Thanks, I will modify these and possibly Procedural Wings, I will upload a hotfix if I'm successful.

I see they call for "FARWingAerodynamicModel", can I just change this to NEAR's aero model? If so, what's the name of it?

Further analysis tells me no.

Edited by Tigermisu

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While modifying Pwings for personal use is fine, you *do* need DYJ's permission before uploading any derivative works, as the license requires DYJ's permission for changes.

The issue is that Pwings looks for the presence of the FAR assembly. You need to point it to NEAR's. (IIRC)

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Both FAR and NEAR use the same names for their internal modules to maintain consistency. You will simply need to make sure that they activate in the presence of NEAR.

Also, please don't violate anyone's licenses in the process. That's not cool.

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sorry I was unaware of that

I changed and made it compatible, thanks for the assitance! Have a kitten:

uQZf2pO.gif

Edited by Tigermisu

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