ferram4

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

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@ferram4 :

Here's the stall angle bug : I rebuilt the SRB rocket, using 4 mirrored av-r8 winglets, launched it, they ripped off, the launch went fine , I selected

'end flight' at about 77,000 meters, went back to the VAB, and now the stall angle says 859.4366! When I first built this craft before launching

the first time, the stall angle did not have that bug.

I built it this way : OKTO 2 core, nose cone, rt-10 SRB, four av-r8's.

So that bug is reproducible for me, I rebuilt the craft 3 times from scratch in a row and got the same thing.

I'll include the okto2 cfg I modded below.

Unfortunately I have been launching stuff including many SRB simple rockets and other debris for about 50 minutes but haven't been able to get

the game to lag to 1fps.

Some other background :

I suspect FAR had something to do with the 1fps bug, but whether it was because of a more KSP program problem, I don't know.

I say so because I only had the setting on 25 max debris for a few weeks, and no problems with slowdown, until I started launching those SRBs -

they had various fins put on all four sides mirrored (all FAR parts), and I ended the flights each time instead of going back to the space

center. I was using far flight assistance each time, and launched maybe 10 different kinds and didnt notice the problem until I tried using the

same simple rocket with 3 normal canards, not placed with the tri-symmetry setting, but two on the side mirrored and one on the back (dorsal?)

side as a vertical stabilizer. That is when the game started at 1 fps on launch pad and didnt stop after I waited up to a minute, no matter what

other craft I loaded, though all the ones I loaded may have had FAR capability on them, I'm not sure.

What's interesting about this canard-SRB craft compared to ones with winglets is that the canards don't disintegrate (vertical launch, no maneuvering just like all the others), it has much lower max Q during ascent (~90 thousand), and around 106,000 meters, the wing leveler starts the roll the rocket back and forth slowly. But when I turn off wing leveler and then back on after 20 seconds, wing leveler stops doing that. All other assistance options besides AoA limiter were on and with default settings. Sometimes I press 'update CoL' out of anxiety while changing nothing else.

The okto2 cfg : http://pastebin.com/RyKnxq8y

The output_log.txt(couldnt get the lag bug to come back though) : http://pastebin.com/RAFqJqWL

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@Camacha: Yes, but it is difficult and is more difficult than stock aerodynamics + Deadly Re-entry. You're welcome to rip your hair out though. :D

challenge accepted!!!

It's pretty fun honestly. Instead of throttling down because the drag is slowing my rocket too much, I have to throttle down because I overbuilt the rocket and it'll overheat and explode from the air compression if I keep it throttled up to max. Clearly an orange tank and a mainsail is too much rocket for a probe guided Münar rescue lander with a Mark-1 capsule. I haven't tried landing yet, because I forgot to power my probe. Like an idiot.

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Here is the promised tutorial video on using this mod with Deadly Reentry:

If you're only interested in the actual reentry technique, you can skip to 10:30.

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so after playing with this i found out a few things LOL...rockets..great on them..deffinately makes it easier to get them to orbit...planes eeehhhhh every design ive gotten of the spaceport flips up and over and into the ground when i take off LOL...

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so after playing with this i found out a few things LOL...rockets..great on them..deffinately makes it easier to get them to orbit...planes eeehhhhh every design ive gotten of the spaceport flips up and over and into the ground when i take off LOL...

Most of my stock spaceplanes did that anyway...

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Here is the promised tutorial video on using this mod with Deadly Reentry:

If you're only interested in the actual reentry technique, you can skip to 10:30.

I would keep a 30 degree AoA while re-entry, and use lots of RCS to keep that flight attitude and avoid tail spin. Typically I start with a 80 x 0 km orbit and turn on RCS at 40km. Then at ~20km the speed should be < 3 Mach and I just point the nose to prograde and turn off RCS

This method is less reliable but much quicker. The wings are stalled so there's no lift

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[...]rockets..great on them..deffinately makes it easier to get them to orbit...planes eeehhhhh every design ive gotten of the spaceport flips up and over and into the ground when i take off LOL...

You might be able to adjust those designs. A while ago in a ferram thread, somebody mentioned to keep the center of lift behind the center of mass (going away from the command pod). For me this works nearly every time in keeping this from happening to me. But if you put the center of lift too far behind the center of mass, the plane will be difficult to pitch up (pull up) at all. Planes that have the center of lift nearly on the center of mass , just a barely visible bit behind it are very easy to pitch. Keeping in mind that the center of mass can move in flight as you burn up fuel, and that could cause instability later while you're going kerbal at mach 7. The total mass changes this too and also the shape of the plane and thrust to weight ratio, which you can get by using Flight Engineer or Mechjeb's in-editor window. If there is a way to fly a plane with the center of lift in front of the center of mass in FAR, I haven't really tried with that, planes tend to go crazy on takeoff in that case.

What would be really useful is a display in editor to see where the center of mass moves to at all points between full and empty of any tanks you'd choose. That's probably something only the KSP dev guys can do though I guess. Because sometimes it is too hard to take apart planes to see the change if a fuel tank is gone and then put it all back together.

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If there is a way to fly a plane with the center of lift in front of the center of mass in FAR, I haven't really tried with that, planes tend to go crazy on takeoff in that case.

In real life you need fly-by-wire with artificial stability enhancement.

In KSP you can do it with Lazor, but the default PID settings aren't good for FAR. I have set I've been working on and will work on more now that it the PID settings are persistent, but that may be a while ...

In the meanwhile you can start here if you want to have a play with it:

Roll M: 1/0.1/0.01
Roll A: 0.3/0/0
Yaw: 0.4/0.055/0.06
Pitch: 0.001/0.2/0.001

What would be really useful is a display in editor to see where the center of mass moves to at all points between full and empty of any tanks you'd choose. That's probably something only the KSP dev guys can do though I guess. Because sometimes it is too hard to take apart planes to see the change if a fuel tank is gone and then put it all back together.

Just do the full/empty and use the Tac Fuel Balancer mod from spaceport.

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Hi there,

I keep going back and forth between installing and uninstalling FAR. The built-in aerodynamics are extremely frustrating, but FAR adds its own set of quirks as well :/ One of my major points of confusion though is that I'm never sure how exactly FAR interacts with non-stock parts and addons.

- Apparently B9 is now FAR compatible, but what about Taverio's?

- I'm just going to assume Firespitter and other prop lift packs are out of the question, because I've had nothing but frustration and failures with them.

- Does MechJeb's spaceplane guidance get confused by FAR? I've yet to get auto-runway-landing to work, but that may also just be my less-then-stable plane designs...

- Is there a way to reliably tell if given part is generating drag? This is primarily an issue for custom parts. For example, if something "behind" a fairing or nosecone, is that sufficient? Does FAR know if it "sticks out" from the footprint of said nosecone/fairing? Does it matter is the sides are not covered by fairings and are just exposed to the air? Will any of the cargo bay addons mitigate this latter effect (if it exists to begin with)?

- In general, what is required for FAR to take into account a part, and what sort of parts are affected by it? For wings, they have to be specifically coded for FAR support, correct? For nosecones and fairings does it only look for the string "nosecone" and "fairing" or what else is there (precisely)? Are there any other strings it looks for? Can I manually edit cfg files to fill in missing details? Do jet engines need ot be FAR aware in any way? What about air intakes?

- Finally, is it just me, or does FAR make regular vertical ascent substantially more delta-V efficient, due to drag reduction (after proper nosecone placement)?

Sorry about the question wall, it's been driving me pretty batty though... Argh, mod fatigue...

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Er I think my reply got eaten, but I had a few questions that have been bugging me for a long time, and cause me to keep going back and forth with this addon:

- Does FAR interfere with MechJeb's spaceplane guidance? I've never been able to get it to auto-runway-land using FAR, but that may just be my planes.

- If yes, what's a good flying assitance addon that works?

- Is there a reliable way of knowing if FAR is properly "aware" of a given part?

- I know it looks for the strings "nosecone" and "fairing" but is there anything else it looks for, or cares about? For example, how does it handle 3rd party (but aerodynamic looking) cockpits?

- Wing/lift surfaces have to be specifically enabled with FAR, correct?

- To that end, I know B9 is apparently fully compatible now, what about Taverio's?

- Are all rotor-propulsion addons messuped by FAR, or are my helicopter designs just awful?

- Is there a reliable way of telling what FAR thinks the current drag from a given part is?

- To that end generally speaking, does it suffice to have a part "behind" a nosecone or fairing, even if the sides are exposed?

- If not (i.e. exposed sides affect drag, as you'd expect) - can this be mitigated by any of the cargo bay addons? Will they "just work" or do they need any specific config?

- Does it know if something "sticks out" from behind a nosecone - e.g. 1m nosecone on a 2m tank? What about radial attachments - does it just assume they won't be covered?

- Other then lift surfaces and noses, does FAR do anything different with other parts? Intakes? Jet engines? Anything?

- Are all the readouts documented anywhere? The spaceport page and this OP are both pretty spare in terms of info. Not much about them mean much to me - I assume they refer to IRL flight concepts.

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Nevermind, I was confused. The B9 pack has compatibility with FAR. Can anyone comment on the balance of the parts? More possibilities are more than welcome, making it all a bit easier is not.

Edited by Camacha

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In real life you need fly-by-wire with artificial stability enhancement.

[lazor system stuff and tac fuel balancer]...

Thanks! I haven't used that before specifically but I'll take a look now especially that, as I might have thought, just as I gave advice, I built a small low mass plane following my own rules but it is pretty much uncontrollable, so I'll try lazor system on it. I've got Tac fuel balancer too and forgot I had it. I like your Ramjets, which are good for supersonic flight and roasting kerbal pizzas.

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- Apparently B9 is now FAR compatible, but what about Taverio's?

Yes and has been for a while. Its in the readme, although the thread had an outdated description about a separate directory for FAR config files. Since ferram4 implemented overriding of the winglet module, the config files have been merged as of 1.3.3.

- I'm just going to assume Firespitter and other prop lift packs are out of the question, because I've had nothing but frustration and failures with them.

For firespitter you need to go into the configuration files and uncomment the FAR blocks for the wings. You will also have to manually add the FAR Control System module to the cockpits. I've had a chat about it with Snjo and the next version will likely have a merged config like B9 and TV.

- Does MechJeb's spaceplane guidance get confused by FAR? I've yet to get auto-runway-landing to work, but that may also just be my less-then-stable plane designs...

It doesn't know about drag when FAR is on, that confuses it, plus the control delay FAR introduces to simulate fly-by-wire makes it worse. Generally I've found it better to avoid using mechjeb guidance below 30k.

I've talked to r4m0n about adding a function to FAR that MJ2 can detect and read part drag from without having the modules depend on each other, but I simply haven't had time to work on it at all, and that would only help with the ascent ap, the landing ap, and the aerobrake prediction.

Spaceplanes will be an issue for a while, as MJ doesn't do any prediction on the effects of stock winglets undergoing control input, and it certainly does not know about stalls.

- Is there a way to reliably tell if given part is generating drag? This is primarily an issue for custom parts. For example, if something "behind" a fairing or nosecone, is that sufficient? Does FAR know if it "sticks out" from the footprint of said nosecone/fairing? Does it matter is the sides are not covered by fairings and are just exposed to the air? Will any of the cargo bay addons mitigate this latter effect (if it exists to begin with)?

- In general, what is required for FAR to take into account a part, and what sort of parts are affected by it? For wings, they have to be specifically coded for FAR support, correct? For nosecones and fairings does it only look for the string "nosecone" and "fairing" or what else is there (precisely)? Are there any other strings it looks for? Can I manually edit cfg files to fill in missing details? Do jet engines need ot be FAR aware in any way? What about air intakes?

- Finally, is it just me, or does FAR make regular vertical ascent substantially more delta-V efficient, due to drag reduction (after proper nosecone placement)?

Sorry about the question wall, it's been driving me pretty batty though... Argh, mod fatigue...

ferram4 will have to answer some of this.

Things shielded by fairings have the 'is shielded' or something = true in the right-click menu for the part while launched.

Base parts are automatically converted to FAR drag model if the control pod has the far control system module in its .cfg.

Wings need the wing module manually added currently with the correct dimensions and such.

Engines and intakes don't need anything.

Yes ascent is significantly more efficient, or rather, the stock model has way too much drag.

Edited by Taverius

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@Camacha: B9 is completely FAR-compliant; I should know, I'm using it myself. :) You shouldn't have to do anything to make it work properly.

@Percival Meekins: All right, here's some answers:

- If [FAR interferes with MechJeb's spaceplane guidance], what's a good flying assitance addon that works?

FAR already has some built-in control systems; they won't fly the plane for you but will certainly make your designs easier to fly.

- Is there a reliable way of knowing if FAR is properly "aware" of a given part?

Just right-click on it; if it's recognized it should have a flag called "isShielded" visible in the right-click menu. That is used to label whether the part is covered by a cargo bay or a payload fairing, and it happens to be good for telling if the code is running properly.

- I know it looks for the strings "nosecone" and "fairing" but is there anything else it looks for, or cares about? For example, how does it handle 3rd party (but aerodynamic looking) cockpits?

It also tries to identify "heatshield" parts to handle Deadly Reentry properly, as well as "truss" and "plate" parts. All other parts it handles about equally due to some difficulty in determining the shape and properties of some parts.

- Are all rotor-propulsion addons messuped by FAR, or are my helicopter designs just awful?

If you're talking about Firespitter helicopter stuff then everything should run properly; your designs might just become unstable if you move to fast.

- Is there a reliable way of telling what FAR thinks the current drag from a given part is?

Currently not available; you can get an idea of the overall drag from the Flight Data GUI, though.

- To that end generally speaking, does it suffice to have a part "behind" a nosecone or fairing, even if the sides are exposed?

- If not (i.e. exposed sides affect drag, as you'd expect) - can this be mitigated by any of the cargo bay addons? Will they "just work" or do they need any specific config?

If they're only "behind" a nosecone or fairing the part can still produce drag. Cargo bay and payload fairings can negate this, if they are set up properly; I believe that most are set up properly.

- Does it know if something "sticks out" from behind a nosecone - e.g. 1m nosecone on a 2m tank? What about radial attachments - does it just assume they won't be covered?

FAR could easily identify those situations if the size of the attachnodes used by parts made any kind of sense; in KSP the attachnode sizes don't always make sense and most modders don't even bother at all. So, no. Radial attachments are considered to be affected by drag unless they are inside a cargo bay or payload fairing.

- Other then lift surfaces and noses, does FAR do anything different with other parts? Intakes? Jet engines? Anything?

It applies proper drag to other parts, normally assuming that they are cylindrical in cross-section to make things easier. Also, any unused attachnodes (say, on the top of a stack of fuel tanks that doesn't have a nosecone on it) will create extra drag.

- Are all the readouts documented anywhere? The spaceport page and this OP are both pretty spare in terms of info. Not much about them mean much to me - I assume they refer to IRL flight concepts.

There's "Help" and "?" buttons throughout the GUIs; clicking on them will give you lots of info about what's being talked about.

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The first post mentions that wings have different effects, more drag at the wing tips, etc. can anyone give a more detailed description of how this works. I'm particularly interested in how to make a good wing for a heavy ssto.

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Something that I do not quite understand is the speed dropping when you point your nose downward with the engines turned off, for example. I mean, it has been a couple of years since I have been flying, but should you pick up speed as soon as you dive? Or is it some physics that I forgot about or never understood?

@Camacha: B9 is completely FAR-compliant; I should know, I'm using it myself. :) You shouldn't have to do anything to make it work properly.

I finally figured that out, heh. Any words on the balance of the pack? I just built a mach 4,5+ jet on my first try, but I tend to build amazing craft on first tries, only to fail miserably with anything after that. I have no idea whether these parts are overpowered or not. I want more options, but nothing should be easier than stock.

Edited by Camacha

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@Camacha: If you're losing speed while heading downwards that means that your plane brought enough thrust with it to exceed terminal velocity at that altitude; congratulations on your excess. Odds are that whatever planes you've flown in real life haven't had the power to reach terminal velocity on engine thrust alone; that would explain the discrepancy.

I think B9 is fairly balanced, though the S2Widebody Intake Adapter is unbalanced until the next release due to the excessive intake drag it makes, but that's balanced in the direction of "too hard" rather than "too easy." There's also the fact that since they are fairly large parts without new, heavier and more powerful jet engines to go with them which makes flight with the pack more difficult.

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Roll M: 1/0.1/0.01
Roll A: 0.3/0/0
Yaw: 0.4/0.055/0.06
Pitch: 0.001/0.2/0.001

Mention of PID was hard to find, I noticed that those letters aren't in the advanced controller menu any more, maybe that menu is the same as the Advanced controller options menu in the red laser menu. There is torque yaw, pitch, a single roll area and then translate up/down, left/right, fwd/back areas. I don't understand the abbreviations you used , maybe it is a quick way of telling me something about the other fields.

Can you explain what this stuff does, and how it might work or interfere with FAR's flight assistance?. It did save my yaw and pitch torque changes between my flights.

Edit : I just figured out what the Mach/AoA box does in the FAR CAS static aerodynamic analysis tab. Cool!

Edited by localSol

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@Camacha: If you're losing speed while heading downwards that means that your plane brought enough thrust with it to exceed terminal velocity at that altitude; congratulations on your excess. Odds are that whatever planes you've flown in real life haven't had the power to reach terminal velocity on engine thrust alone; that would explain the discrepancy.

Stupid, I could have known. Trying to say smart things late at night is not working out. And you are right, the planes I flew are a tad slower, just a mere 96% :D

Still loving the mod, time to get frustrated by crashing some VTOLs.

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Do you have to edit cfg files of fairings for this mod to work, or does it automatically detect them? If so, does anyone have an example of the cfg edits that have to be made to fairings?

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how would i go about keeping my nose up during reentry? im using deadly reentry so aerobraking is vital. i know the space shuttles used rcs thrusters for attitude control in the upper atmosphere but in ksp the normal rcs thrusters just dont have the strength to keep nose up unless i use an excessive amount of them for which the monopropellant cost is equally excessive. any tips?

http://puu.sh/2JmGe/26000208ff.png

http://puu.sh/2JmH6/4266d47226.png

Edited by MAKC

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The KW Rocketry pack has RCS thrusters specifically made for shuttles. They're streamlined, and also stronger than stock. I like them. :)

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FAR could easily identify those situations if the size of the attachnodes used by parts made any kind of sense; in KSP the attachnode sizes don't always make sense and most modders don't even bother at all. So, no. Radial attachments are considered to be affected by drag unless they are inside a cargo bay or payload fairing.

I'll chime in to say that the B9 and TV pack have appropriate node sizes for all included parts. I even added a few spaceplane part cfgs for stock parts to TV just for the purpose of giving it the right node size.

Actually, ferram, what does FAR think of size 3 & 4 nodes? Can you take a look at the B9 pack and tell me? The game won't take 2.5 as a node size so I had to round as appropriate based on my understanding of it.

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Do you have to edit cfg files of fairings for this mod to work, or does it automatically detect them? If so, does anyone have an example of the cfg edits that have to be made to fairings?

I'd be interesting in knowing this as I have several fairings made using the "fairing factory" if I knew these would be effected by the mod I'd download this and install tonight :D

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