[1.3.1] Ferram Aerospace Research: v0.15.9.1 "Liepmann" 4/2/18

[ferram4]

Cargo bays should be fine with this version.

[ayana]

Oh this is very nice. Thanks for the cargo bay fixes.

[Velant]

I'm reinstalled KSP, install only FAR without any other mods - tweaking not working with FAR.

[Velant]

Ok i find, FAR not working without that annoying toolbar whis always appears in center every time when game go to another screen and i need constantly move it to border.

[ferram4]

FAR has a hard dependency on the toolbar; this is stated in the FAQ and in the readme. I don't know what issues you're having with that, but you'll need to take it up with blizzy if the toolbar info isn't saving settings properly.

[theSpeare]

Currently running very smoothly. Great work, thanks.

[wasmic]

Yay update! Now I won't have to wait two minutes for my rockets to reach 10km anymore!

[NathanKell]

Ferram, it's really ironic that it took breaking rockets when node size is wrong to finally get modders to fix their node sizes...just as you're working on an update that makes that no longer necessary for FAR.

[KerikBalm]

So... I'm contemplating installing this mod, but I see this statement:

"wing pieces at wingtip make less lift and more drag than ones at wing root"

This makes no sense to me? Making high aspect ratio wings will perform worse than low aspect ratio wings?

0.o ?

[BudgetHedgehog]

Hey, ferram... I don't know why, but my engine is creating drag inside its fairing.

Apparently, it's not shielded, which is interesting..

Also, don't know if this is something with FAR, but my solar panels can get sunlight inside their fairing DESPITE the isShielded value being true.. hmm...

[Tidus Klein]

Well to answer your first problem, The in game engine fairings don't even have a collision mesh, and I think (don't quote me) that it is how FAR calculates drag, using the collision mesh. Just think of it as the fairing producing the drag not the engine.

as for the second......I dont know, but I do know that Proc Fairings don't have collision meshes on the bottom or top of the fairing, (again needed to detect if in sun or not,) and by the looks of your pic the sun may be coming in under your fairing where there is no collision mesh.

hope that helps

[thorfinn]

Skin drag is a thing, you know Also you probably aren't exactly at zero angle of attack. And the automatic fairings are not the same thing as the user-defined fairings that give the "shielded" attribute.

That fairing piece is dragging with just 11.8 kg of force, I don't know your speed but it doesn't look excessive out of hand.

By the way, @ferram, technical question: is there a way to access the VAB aerodynamics simulator while in flight? Could an external mod retrieve an L/D curve for the current craft? Doesn't need to be extra fast, I'm rethinking an old idea of mine

[GavinZac]

Also, don't know if this is something with FAR, but my solar panels can get sunlight inside their fairing DESPITE the isShielded value being true.. hmm...

There's nothing that can be done about that really without making a whole new Solar Panel module. That is; FAR never did this, nor intended to. It's an aerodynamics mod.

[BudgetHedgehog]

Well to answer your first problem, The in game engine fairings don't even have a collision mesh, and I think (don't quote me) that it is how FAR calculates drag, using the collision mesh. Just think of it as the fairing producing the drag not the engine.

as for the second......I dont know, but I do know that Proc Fairings don't have collision meshes on the bottom or top of the fairing, (again needed to detect if in sun or not,) and by the looks of your pic the sun may be coming in under your fairing where there is no collision mesh.

hope that helps

1, a fair point and a compromise I can live with

2, they are KW fairings and the sun was, I think, basically directly overhead. While it's true that even KW fairings have no collision mesh (like, at all, I think), I think some other panels weren't generating electricity. Mybe it'd if ferram were to include a line somewhere saying 'if a panel isShielded value=true, make it not produce electricity' or something, I dunno.. really quite a minor problem, I'll admit

Skin drag is a thing, you know Also you probably aren't exactly at zero angle of attack. And the automatic fairings are not the same thing as the user-defined fairings that give the "shielded" attribute.

That fairing piece is dragging with just 11.8 kg of force, I don't know your speed but it doesn't look excessive out of hand.

Yeah, that'd be why then - automatic engine fairings aren't recognised by FAR. And yeah, quite a minor little thing, I know that

There's nothing that can be done about that really without making a whole new Solar Panel module. That is; FAR never did this, nor intended to. It's an aerodynamics mod.

Ah, I see. Didn't realise it'd be that complicated - consider this struck from the record. Apologies ferram!

[ferram4]

@NathanKell: Tell me about it. However, I still want to get rid of the dependency since it doesn't work properly for off-size parts and still allows for strange behavior if the player decides to try and break the system.

@KerikBalm: That's correct; the outer parts of the wing make less lift and more drag than the inner parts of the wing, which is how high AR wings are so much more efficient at creating lift.

@ObssessedWithKSP: That is correct, because the engine fairing still has skin friction drag acting on it and is considered part of the engine itself in the calculations (except for the part where the mesh is attached to the decoupler). If that weren't the case then the engine + fairing combo would make no drag at all, despite the fact that the fairing is exposed to the elements.

Also, I can't override the solar panel's method at all. Those things should be private (or at least protected) members of the class, so I can't do anything to mess with it at all, short of extending the class (if it's only protected) or having to recode the entire thing (if it's private) either way, outside the scope of this mod.

@Thorfinn: I have been thinking of setting FAR up so that the Flight Data window (in flight) and the Editor Analysis stuff can dump information to a text file, would that work? I was thinking more for debugging purposes, but I think that would work for what you're thinking of.

[Zardiz]

Seriosly? is no one else having issues with this mod right now? I cant even get into orbit anymore with this mod installed. Already before 23.5 I had bug where faring removal in space caused some magical force to totally mess things up, like all of sudden my gimbal was locked during circularization, but only after the farings were removed o_O, that bug went away somehow. Now I cant even do gravity turn without all hell breaking loose. I've never had this much trouble with this mod to be forced to just remove it to get my stuff in orbit.

[ferram4]

What are you launching and how are you flying it? Are you launching a rocket with an initial TWR greater than 1.6, going straight up to 10km, then pitching over 45 degrees like in stock KSP? Or are you starting with a low TWR, starting your gravity turn at ~50 m/s, and staying close to prograde the entire way up?

Many people have the same complaint that you have about "not being able to put something into orbit." It almost always stems from using habits developed for stock KSP, but then using them in FAR-KSP.

The fairing issue sounds like a bug, but it's probably caused by something else, since that sounds like they didn't detach properly; what fairing mod was it that caused that issue?

[Zardiz]

To start with the faring issue, its farings from KW, expanded 3.5 Model, at least visually they all detached proerly. As I was unable to find any cause for this I decided to remove FAR and this didnt happen anymore.

TWR is about 2 at launch, I start the gravity turn at about 5KM -170 m/s - with 2/3 throttle, starts out ok if im reeaaally careful, but as soon as I try a bit more steep angle of attack, it flips over instantly. What im launching is simple science vessel inside 2.5 faring. My first model is a bit bigger (same cargo) just more Delta-V (extra stage), that one was a bit tall so I removed the bottom stage but pretty much the same issue. I've used your mod for ages now, it feels like the aerodynamics are on some aggro mode compared to past experiences.

I dont know, I've put much bigger cargos up before without issues (Interstellar's reactors), but today, I gave up trying after hours of trying to find out what can cause the bigger ver. behave totally uncontrollably, scale down and find out its not the craft, but something else. Sigh.

[BudgetHedgehog]

To start with the faring issue, its farings from KW, expanded 3.5 Model, at least visually they all detached proerly. As I was unable to find any cause for this I decided to remove FAR and this didnt happen anymore.

TWR is about 2 at launch, I start the gravity turn at about 5KM -170 m/s - with 2/3 throttle, starts out ok if im reeaaally careful, but as soon as I try a bit more steep angle of attack, it flips over instantly. What im launching is simple science vessel inside 2.5 faring. My first model is a bit bigger (same cargo) just more Delta-V (extra stage), that one was a bit tall so I removed the bottom stage but pretty much the same issue. I've used your mod for ages now, it feels like the aerodynamics are on some aggro mode compared to past experiences.

I dont know, I've put much bigger cargos up before without issues (Interstellar's reactors), but today, I gave up trying after hours of trying to find out what can cause the bigger ver. behave totally uncontrollably, scale down and find out its not the craft, but something else. Sigh.

Do you have TweakableEverything installed? I had a KW fairing issue a while back, turned out TE was messing with the decouple force. If not, it's probably worth asking in the KW thread - as was pointed out to me earlier, FAR is an aerodynamics mod. It has literally zero effect in space.

Second, your ascent method is what's screwing you up - you have too high a TWR at launch (especially with 2/3 throttle.. that's not just FAR, that's bad rocket design - you obviously don't need the extra 1/3 throttle, why have an engine that can give it? It's just extra weight to carry up) and are moving too fast and too high at the gravity turn. Seriously - ferram mentioned a very slow turn starting at about 50 m/s and not straying very far from prograde. This is what you should do. In actual fact, a bigger and heavier cargo (like nuclear reactors) can help with stability as it moves the CoM higher making it easier to control, as you found out. When your CoM is too low, you'll have trouble, especially with that ascent profile. You probably want to start turning at around 1km high or so - that should be when you're travelling between 50 and 100 m/s, providing your TWR is around 1.3 at launch (which it should be) and start turning veeeeeery gradually. Once you're about 10 degrees off vertical, I find it's actually better to turn off SAS and let the rocket fall into the correct angle by itself. By about 35km high, the air is much thinner so you'll need it back on to stabilise you again. Also, you do have stuff like fins at the bottom, right? They help point your rocket right tremendously.

Try these and ferrams tips and see if they help. You'll be surprised how different a FAR launch is to stock once you know how to do it correctly.

[ferram4]

Without a picture of the craft, we can't do anything more than hopelessly speculate about what you're doing, but the high TWR and high speed for the initial pitch over makes me think that you brought too much engine for the rocket you have.

[goldenpeach]

Is it normal that a rocket I design yesterday in the previous version of FAR was working very well and that with the new version of FAR it flip out of control before I even reach 3KM(same design, same flight path)?

[Zardiz]

TWR with max is 2, not with 2/3. Well I guess I am uncabable of lauching small things anymore, as I described, the bigger one is 100% uncontrollable after I attempt to start the gravity turn. I still fail to understand why I've never had issues before....

I apriciate the tips, but I think I will disable this until I have the need for bigger payloads in general since I've never had issues like this.

EDIT: goldenpeach, cant say im using the same craft, but as I explained, I am experiencing issues I've never faced before with FAR.

Yeah Ferram4, I understand that. But after hours of trying different things, I dont know what to say...

Edited April 3, 2014 by Zardiz

[BudgetHedgehog]

TWR with max is 2, not with 2/3. Well I guess I am uncabable of lauching small things anymore, as I described, the bigger one is 100% uncontrollable after I attempt to start the gravity turn. I still fail to understand why I've never had issues before....

I apriciate the tips, but I think I will disable this until I have the need for bigger payloads in general since I've never had issues like this.

EDIT: goldenpeach, cant say im using the same craft, but as I explained, I am experiencing issues I've never faced before with FAR.

Yeah Ferram4, I understand that. But after hours of trying different things, I dont know what to say...

The point is at max throttle, you should only be starting with about 1.3 TWR. Any higher is unnecessary weight. And launching small things is completely doable, you just have to scale down your engines as well to keep the 1.3 TWR at launch.

If you want help and to stick with this, a picture of your craft in the VAB with the CoM and CoT enabled would help us help you design a better FAR rocket.

[Amaroq]

I wonder if the issue Zardiz and goldenpeach are having has to do with the new strength of nodes -- e.g., if the previous versions of those rockets / flight plans were flexing more, and therefore giving more time for SAS, gimbal, and drag to straighten the rocket out, while with the new rigid nodes, the deflection causes the entire rocket to turn more instantaneously, leaving less time for correction.

At any rate, @Zardiz, starting your gravity turn at 5km is much too late - it sounds like you are trying to make a "sharp" turn, and the drag forces are sending you tumbling. (Trust me, I have lots of experience at tumbling my F.A.R. rockets!) .. you can actually start the turn, say, the initial 5-10 degrees of it, almost as soon as you're clear of your launch clamps, and keep (slowly) nosing over through the entire flight, never exceeding about 10-degrees off of the existing ground-speed "prograde" marker.

[goldenpeach]

The rocket were working fine in 23.5 with the previous version of FAR, does FAR have increased the strength of nodes?