[1.8-1.12] Ferram Aerospace Research Continued: v0.16.0.5 "Mader" 03/04/22

[DA299]

9 hours ago, RunaDacino said:

Is it possible, in FAR, to push jet engines higher than their mach number indicates?

 

Afterburning "Panther" engines, no matter what design I use, cap out at around 970 m/s before rapidly losing thrust. Is it possible to hit mach 3 and maintain it in level flight using procedural wings and Panther engines, or do I need whiplashes? (I'm asking for sake of career saves and "planes with purposes", with Whiplash i can hit very good speeds easily).

FAR really doesn't do anything to Jet Engines afaik. AJE is the mod that changes jet engine parameters. Although I very much doubt you could hit Mach 3 with stock Panthers (without AJE). If you look at the Kerbal wiki for Panther engines, you'll see that it drops off in thrust very quickly after ~Mach 2.7. So maybe try cruising higher but I doubt you could do better than 970 m/s

[kcs123]

On 5/4/2024 at 9:37 AM, RunaDacino said:

Also! How do you deal with landing gear and its introduced drag... since AFAIK none of the mods allow building the gear housing INTO the wing/fuselage properly. I'm mostly using B9aero, Mk2 stockalike, b9 wings, Near future and foundry.

Can't give you precise answer regarding engines, might be wrong on that one. As for landing gears, what do you meant that you can't build housing into wings or fuselage ?

That is almost mandatoray for me to clip landing gears into fuselage/wings. Deliberatly creating thicker wings to be able to hide landing gears into wings. Once you place landing gear on craft, you can offset postion in a way that only landing leg and wheel stick out when landing gears are in down position. And with gears up, everything is hidden inside wing/fuselage, or at least almost everything, depending on used part. B9 wings can also hold a fuel, so, being thicker is not ultimately bad thing.

I was not activly played KSP for a while, so can't tell if Kerbal Foundries mod still work on latest KSP. But I highly recommend it to try. Especialy adjustable landing gears.

 

 

Edited July 18 by kcs123

[RunaDacino]

Hello!

 

I've tried searching, but came out empty. Using Procedural Wings, how do I best go about setting up leading edge slats, flaps and other leading edge devices in FAR so that they respond appropriately to control input? I want to try and enhance my spaceplanes' low speed performance without making their wings too massive.

 

Also to earlier question: I'm using Kerbal Foundries. The wheels are often larger than even thicker wing settings I use when scaled sufficiently for ground contact with maximum strut extension. However, I did find ways to minimize their drag so it's fine.

Edited May 19 by RunaDacino

[RunaDacino]

 

Parts with ability to intake air, and also atmosphere that have b9partswitch to replace intakeatm with other fuels cause nullreference exception spam. Linked to original report with logs in the thread.

[RunaDacino]

When making patches for turning wings in mods compatible with FAR, what are some easy ways to generate the required data for control and lifting surfaces?

 

The mods in question are firespitter and coldwaraerospace

[RunaDacino]

On 4/19/2019 at 4:02 PM, Kitspace said:

Hi guys!

Does anyone know what aerodynamics model does FAR use?
What parameters are assumed from the voxel model shape, and what information is taken from the wings config files?
What kind of airfoil or lift curve shape does it assume for the parts it classes as "wings"?
What about body lift?

Thank you!

This looks like to be the "main" file for the atmospherics model.

https://github.com/dkavolis/Ferram-Aerospace-Research/blob/master/FerramAerospaceResearch/FARAtmosphere.cs

I recommend cloning the codebase locally and using some kind of IDE that has a linter/langserver able to handle unity/C#. I think VSCode might be suitable. Afterwards, you should be able to track down all the functions and procedures that get called by this file. 

 

 

 

[RunaDacino]

After launching complex craft and returning to KSC, and launching more crafts - using Kerbal Construction Time - eventually something in FAR breaks and it begins to spam mesh render and null exception errors.
This happens only in atmosphere, leading to a physicsDelta of 40% on the launchpad even on a 50-60 part craft that normally moves around 90-100. On pressing launch, it then drops down to 10-20% with frame dropping and stutters. 

 

Logfile: https://drive.google.com/file/d/1l3qDhVrvgT_SIKioU10GTXEVxxLri34X/view?usp=sharing

Modlist:https://pastebin.com/bu5tTL3M 
Noting: I've experienced this issue with and without scatterer, with and without kerbinside/GAP+extras so I believe it is likely ferram at the root.
Noting: I have made a few custom patches to MKS and tech tree to suit my playstyle, but none interact with aero.

The craft in question:

Spoiler

I've made it twice using Kerbal Construction Time, duplicating the first copy. First launch went smoothly at like 80% physicsDelta (using katz' utility that displays it). Second launch broke and forced me to quit and restart. On restart, the issues disappeared.

 

PC properties:

Win10 64bit "N" Home edition, Ryzen 5 5500, 16Gb 3200 MHz DDR4 RAM, GTX1050Ti, KSP is running on my 512 GB with 250 Gb free SATA system SSD.

 

Reproduction steps:

Make multiple launches to orbit using Kerbal Construction Time's launch method. Sometimes, something breaks and your next launch starts to stutter.

Reproduction reliability:
Very low, I cannot rightfully predict it. Sometimes I can fly planes for hours, landing them and whatnot and no issues occur. Sometimes, I quickload in-atmosphere or revert a bunch and it occurs much earlier. Other times I can do 8 launches back to back without issues. 

Potential cause maybe:
Could Decoupler Shroud mod cause issues with voxelization? I've seen it cause issues before in VAB forcing me to mess around.
Furthermore, I alt tab a lot as I use low-TWR engines a lot and my burns are atrociously long. However, this is usually done in orbit. 

Edited June 7 by RunaDacino

[Pauver]

Does FAR still make water unbelievably buoyant? I cannot have a craft splashed down without it bouncing around like crazy

[Derpistheword]

On 6/11/2024 at 10:22 AM, Pauver said:

Does FAR still make water unbelievably buoyant? I cannot have a craft splashed down without it bouncing around like crazy

Yes and on top of that the values for lift and drag become undefined / NaN underwater

[miklkit]

Installed FAR for some spaceplane performance.  Found a FAR icon in the SPH and it brought up charts and stuff.  I get that green is good, light green is ok, and red is bad.  But I have no idea what all those values mean or what to change.  Is there a manual for FAR somewhere?

[capi3101]

Key bit to know on those analyses is that the specific numbers don't matter all that much. If you've got a red value, your plane will have an unstable aspect to its flight - end of story.
M_w is the key one to note if you don't want your plane to be flip happy. Standard advice there - move your center of lift back or your center of lift forward. Possibly both.
There's another one but I forget which one specifically it is - one of the Ls. If it's red, you haven't got enough tailplane. Typically that one really only matters if you expect to be maneuvering a lot at high speed.

I'd recommend installing RCS Build Aid here to see what happens with your CoM as the fuel drains.

Check these benchmarks: Mach 0.5 at 0k, Mach 1 at 10k, Mach 2 at 12.5k, Mach 3 at 15k, Mach 4 at 20k.  If you're green on all those numbers, you should* have stable flight through all the regimes.

With the dynamic graphs, again it's not the specific numbers so much as the shape of the graphs. A graph that starts off with a sine wave with big amplitude on the left that tamps down to the right is dynamically stable. And vice versa. Same general tips for fixing things - it's either adjust the CoM or add/subtract tail.

There is a manual for FAR out there. Bless me if I can remember where it is though, and it'd be a little out of date even if I did know where it was. I also used to have a site that explained the dynamic graphs but I seem to have lost the link...

[miklkit]

Thanks for the info.  I use Fill It Up to check CoM as the fuel drains.   I used spaceplanes that are stable in stock aero but are having lots of trouble in FAR.  They do everything from flying straight into the water to flipping just before landing to simply exploding, and I have no idea what to change to improve them.  The charts mean nothing to me and I have to just make random changes and see what happens.  So far it is not worth the effort.

[capi3101]

2 hours ago, miklkit said:

Thanks for the info.  I use Fill It Up to check CoM as the fuel drains.   I used spaceplanes that are stable in stock aero but are having lots of trouble in FAR.  They do everything from flying straight into the water to flipping just before landing to simply exploding, and I have no idea what to change to improve them.  The charts mean nothing to me and I have to just make random changes and see what happens.  So far it is not worth the effort.

Flying straight into the water: move your CoM forward, and/or add more pitching surfaces. Try something like a Tail Fin (or even an AV-R8 on a smaller plane), something where the entire surface moves (i.e. avoid something like the Delta Deluxe, where there's only a little bit of it that actually adjusts itself - those are decent for ailerons, but you want more pitch control than anything else). 

Flipping just before landing: which direction? If it's flopping over on its belly trying to land upside down, move your CoM upwards. Pitching upward uncontrollably - try moving the CoM back, or try landing at a higher speed. I'd have to watch your approach to see what's going on there.

Simply exploding: curse a lot. It doesn't fix anything but at least you'll feel a little bit better.

Another thing to do is make sure you've got dedicated control surfaces. Adjust your pitching surfaces to 100% pitch and 0% everything else. Same goes for your ailerons (100% roll) and rudder (100% yaw).

I might also suggest a fly-by-wire mod. I use AtmosphereAutopilot myself; I've used it with FAR for a decade now.

[miklkit]

FAR has a lot less low speed drag, does it also have less low speed lift?  Maybe they need more wing? 

Could too much control surfaces cause "porpoising"  up-down-up-down until explosion?

The flipping on landing:  It made it to orbit and came back down normally.  It took forever for it to slow down enough to land and just as it was getting ready to touch down at under 80m/s it suddenly went vertical, the tail dragged the ground, and it pancaked in. 

[capi3101]

14 hours ago, miklkit said:

FAR has a lot less low speed drag, does it also have less low speed lift?  Maybe they need more wing? 

It's modeling realistic aerodynamics, so that's probable. I'd have to look at your designs to know for sure.

14 hours ago, miklkit said:

Could too much control surfaces cause "porpoising"  up-down-up-down until explosion?

I've seen it happen myself, so yes. In my experience, though, that's a symptom of not setting up dedicated control surfaces, and it's something that a fly-by-wire mod should smooth out (assuming there aren't other inherent issues with the craft).
 

14 hours ago, miklkit said:

The flipping on landing:  It made it to orbit and came back down normally.  It took forever for it to slow down enough to land and just as it was getting ready to touch down at under 80m/s it suddenly went vertical, the tail dragged the ground, and it pancaked in. 

Okay - that does sound like a stability issue. I'm going to gather a few ingame images of one of my planes and hopefully I can show you what you need to be looking for; I'll try to post again later today. I will say that my own designs typically land at higher speeds than 80. That might go back to needing more wing.

Edited July 3 by capi3101

[miklkit]

Well, here come a few pics.  I've been going through my planes from small to large and here are some. 

This is a MK2 that has been all over the system in stock.  It just took off and is just veering left and is starting to break up. 

This is a slightly larger one that I added a bigger tail to, and it is just starting to go left and break up.

This is a hunk a junk MK2.5 rover carrier that I did for LOLs.  In stock it has enough range to get to the Mun and can land fine.   In FAR it might be my best one so far.  It made it up and came back down and would have landed well except the ground was too rough and it bounced and crashed.

[capi3101]

Wow. From the pics, I'm inclined to give you a diagnosis of "you're going too fast at the altitudes indicated and your planes are disintegrating thanks to a combination of excess dynamic pressure and insufficient yaw authority." I try not to accelerate above Mach 1 (343 m/s) lower than 10 kilometers up - Mach 2 (686 m/s) at 12.5 kilometers, Mach 2.5 (858 m/s) at 15 kilometers, Mach 3 or higher (1029) at 20 kilometers. I definitely don't have any rockets lit below 29 kilometers, which is about as high up as you can get and still have RAPIERs on air-breathing mode. 

The first one is Mach 1.72 at 1899m; the second one is Mach 2.28 at 2863m; the third is Mach 1.05 at 2800m. Try punching the numbers into FAR for the static analysis on the first two for those variables. I'd wager good money the L_β is in the red. 

How's the pitch authority on those planes at low speeds? I'd wager it's sluggish. Try a pitching surface that's not on the same front-to-back axis as the Center of Mass. You can also increase the deflection angle to see if that helps.

What's your launch TWR? Planes are good at 0.55 or so in FAR; I've got an eight-passenger plane that does about that. Not the most fun to fly, but it's reliable.

[capi3101]

Ah! I found that site I mentioned that discussed stability again. Here's the link.

[DA299]

@miklkit I might have some pointers for you.

• FAR models realistic aerodynamics, and in real life, there are very few planes that can fly at that speed when flying that low (they have to be specially designed for it). Mach 1 should not be breached below 7 kms, Mach 2 requires around 14-16 km, Mach 3 and up should be flown over 20 km for maximum efficiency. Of course these are guidelines only, it is possible to design around them, but you need to have good knowledge of how FAR works. 
• You also need to keep in mind that in FAR, the authority of your control surfaces is diminished quite a bit, so you need to increase their area somehow.
• Stock SAS is terrible at flying things in stock. Its better to use FAR's own stability toggles, or even better, atmospheric autopilot to fly planes.
• Lastly, designing spaceplanes in FAR in actually not a trivial task. This is because a spaceplane needs to fly well and be controllable at three very different regimes, low speed(for takeoff and landing), transonic to supersonic speeds (transition, must have a low enough drag to breach the sound barrier), and of course the hypersonic regime to actually reach space and remain controllable in reentry. Aircraft can be made that perform well in 2 out of 3 of these regimes, but one of them has to almost always be compromised somehow. For example, most of my delta-winged spaceplanes take off over 100 m/s when fully fueled, and land at ~80 m/s when empty (with lots of flaps and leading edge slats). They're also quite squirrely and hard to control at low speeds, though they fly really well once over 200 to 250 m/s.

[miklkit]

Ok, UNCLE.  I give up.  I've been working on a dedicated plane just for FAR and it does not fly.  It is lucky to get to the end of the runway.  Back to stock I go.  The only reasons I have been trying FAR is that new mods I got have engines with odd power profiles that are too sluggish at low speed and too strong at high speed, but they work in FAR.  Also, a MKIV cargo plane has a bug where everything in the cargo bay has drag, which makes it not want to go supersonic, much less orbital.  FAR fixes that.  I will work that out in stock.  Thanks for the information here.  Wish I could use it.

[DA299]

5 hours ago, miklkit said:

Ok, UNCLE.  I give up.  I've been working on a dedicated plane just for FAR and it does not fly.  It is lucky to get to the end of the runway.  Back to stock I go.  The only reasons I have been trying FAR is that new mods I got have engines with odd power profiles that are too sluggish at low speed and too strong at high speed, but they work in FAR.  Also, a MKIV cargo plane has a bug where everything in the cargo bay has drag, which makes it not want to go supersonic, much less orbital.  FAR fixes that.  I will work that out in stock.  Thanks for the information here.  Wish I could use it.

Send me the craft files. I'll make it fly and then hopefully you can understand what was wrong with it. (Might have to make some big changes.)

[miklkit]

Where are the craft files located?  Not that it matters as I have already deleted FAR and all the planes I flew in it.  Sorry.

[capi3101]

2 hours ago, miklkit said:

Where are the craft files located?  Not that it matters as I have already deleted FAR and all the planes I flew in it.  Sorry.

Anything you built and saved in the SPH will be in C:\Kerbal Space Program\saves\<your_savename_here>\Ships\SPH, assuming you're playing on PC with the standard install prodcedure for the vanilla game (that it's modded makes no difference).

Sorry to hear that you're giving up on FAR. I completely understand your reasonings why and hope you're not completely adverse to trying it out again at some point in the future.

Just for the hell of it, were I to put together a tutorial, do you think it would be better as something folks could read or something like a YouTube video? Been a while since I did one of thems and my box is a hell of a lot more capable these days than it was the last time I put one together.

[Xt007]

I admit this issue is my own doing for having a mish mash of mods installed.  When I launch a craft, on load I will randomly get the green bounding box drawn.  I've confirmed FAR is the cause as the check box in the FAR debug menu to draw the bounding box is set to true.  This randomly happens, I can simply disable the drawing of the bounding box in the debug menu when it decides to load a craft in flight with the bounding box drawn.  Wondering if anyone is having a similar issue or has any suggestions as to an alternate solution to stop whatever it is that's randomly enabling the bounding box to be set to draw in the debug menu.

Edit:  It seems logical to me that if Ferram is detecting a certain error it would set the debug bounding box to true.  I looked through the dlls and couldn't find any logic suggesting this though.

Edited July 5 by Xt007

[miklkit]

21 hours ago, capi3101 said:

Anything you built and saved in the SPH will be in C:\Kerbal Space Program\saves\<your_savename_here>\Ships\SPH, assuming you're playing on PC with the standard install prodcedure for the vanilla game (that it's modded makes no difference).

Sorry to hear that you're giving up on FAR. I completely understand your reasonings why and hope you're not completely adverse to trying it out again at some point in the future.

Just for the hell of it, were I to put together a tutorial, do you think it would be better as something folks could read or something like a YouTube video? Been a while since I did one of thems and my box is a hell of a lot more capable these days than it was the last time I put one together.

Ah, found it.  I deleted all the planes I made in FAR because they contained parts that I no longer have.  Pity.  I liked some of those parts.  Hmm, it doesn't seem to want to put a zip file here.  Oh well.

I suspect the problem was me working with no information at all and not understanding the problems.  Maybe they would have flown if I had just let them climb steeper thus limiting their speed.  But then there was the takeoff, porpoising, and landing problems. 

This one made it to orbit but could not land.  It was a MK2.5 that had already made it to Vall and back in stock. 

This was the MK2.5 based one that was a dedicated FAR build.