Aerodynamics Debug [F12] not accurate

[Soviet03]

No Claw I don't think you're fully understanding what I mean or what the OP means. - The MK1 fuel tanks DON'T suffer from the bug where one side of symmetrically placed tanks won't produce proper body lift/ just behaves oddly. In your image your MK1s were all perfectly displaying blue lines unless I missed something. You're seemingly trying to say that the bug could just be with the overall and I'm declaring right now that that's false in regards to the issue I'm having, because it DOES noticeably affect aircraft flight performance. I've spent days testing this.

Now what I think is causing some of the confusion is that neither of us probably fully understand how or what the overlay is exactly trying to show hence its strange behaviors - However with MK1 those behaviors are symmetrical hence the point of this entire bug report. It does seem to me like you're trying to downplay the issue especially when you said MK1 parts "suffered" from the same bug which as far as I've seen in your images is simply unsubstantiated.

PS: Is there a way I can imbed the .craft file right here via the forums? Not seeing the usual tabs under advanced edit.

PPS:"Otherwise all of these wacky contraptions would probably be going out of control at some point" - Some do. However also keep in mind this bug seems to ONLY affect 1 part. If I have multiple fuel tanks ONLY 1 on either side will be missing its drag/otherwise behaving oddly therefore the creations you've made would produce a VERY small effect. In other words if I have Skylon 2 engine/fuel pylons on each wing only one on either the left or right side would be experiencing this issue based on my testing. The aircraft you've made in my eye are not the best examples to produce noticeable effects.

Bare in mind I don't want to come off as insulting but I am passionate about this bug because i've had to quit KSP for now.. I've spent days testing this, what I think you're trying to imply simply isn't the case. The issue I'm experience does indeed predictably mess with flight performance in sensitive situations. Tested across several, several test aircraft. Believe me I thought at first it was something I did wrong. - Not the case. I feel I applied the proper scientific method in testing my hypothesis, further research is great and should be done however saying that we don't feel it's actually affecting the aircraft is an assumption which has already been disproven as far as I'm concerned.

Nugget of logic - There may well be a combination of issues at play here, I don't disagree with that. However what is certain is that there is indeed an aerodynamics bug making certain aircraft impossible to fly properly. - The only [visual] connection to that we can see is the aerodynamics overlay of which none of us fully understand.

Edited August 5, 2015 by Soviet03

[sal_vager]

I have to stop you there, I'm not convinced there is any bug here, the aero display lines are inaccurate and for rough indication only, I know this because I was talking to the guy who made them at the time, and as they are just a debug tool and not intended for use during play there are no plans to improve them.

This picture however, shows that there is no difference in lift (or drag) between radial mounted rocket fuel tanks.

Flight testing also shows nothing more than the usual slight drift that all planes have had since Chad made the c7aerospace pack years ago, which, just like unattended craft rotating in space with SAS off, is a product of floating point rounding.

This is why SAS exists, to hold craft steady, expecting craft to stay put with SAS off is unrealistic.

Claw has said at least three times in this thread that there is no actual gameplay problem here, the only "bug" reported is the mismatched lines, which do not matter.

You are going out of your way to prove a bug that isn't there, I'll say what Claw said but in simpler terms, There is nothing to be learned from the length of the aero overlay lines, they are not accurate and were never intended to be.

I'm marking this one down as not-a-bug, nothing in the debug menu is guaranteed to work, if you have an issue here you need to find some other way to prove it than relying on a known inaccurate "feature".

Upload your affected craft to dropbox, post the link here and we'll see what's going on.

[Claw]

No Claw I don't think you're fully understanding what I mean or what the OP means. - The MK1 fuel tanks DON'T suffer from the bug where one side of symmetrically placed tanks won't produce proper body lift/ just behaves oddly. In your image your MK1s were all perfectly displaying blue lines unless I missed something.

Well, I suppose my point is that people aren't looking because they are hung up on the obvious thing. I didn't have time to mark up every photo, but take a look again at the Mk1 pictures. Look really close at the Mk1 fuselage on the underside in that photo. It does not have a cyan line. The same thing is apparent in the in the last picture in the sequence also.

Note the Mk1 on top does have a line, but the one under does not. Also, neither tank on the sides have lines. And this bug doesn't affect only one part. I have four parts that do it, plus unposted pics of the sci jr. Even if the Mk1 is hartd to see, go look at the FL-T400 again.

Also, I don't know if you looked at this picture, where the lines aren't even pointing the right way.

If you want to upload a .craft, use a site like google drive, dropbox, or mediafire and post a link here.

You are right, I am not seeing your real concern here because all of the hard data is reliant on a piece of the game that I do not trust. That is the reason I posted all that above. To say stop pointing at and trusting the overlay. I am very sorry that whatever issue you are having has caused you to quit KSP. I dedicate most of my playtime to finding and fixing bugs for others, because for some reason I want other people to enjoy this game as much as I have. It is incredibly hard to get into some of these bugs. With only someone else's subjective assessments of a plane with no craft files, it takes me days to even guess what you are really seeing.

I also never said I don't believe you. I just said I am not convinced, and that's because I haven't seen whatever it is that you are seeing. I'm not trying to be difficult here. I am literally begging for help.

Edited August 5, 2015 by Claw

[DasValdez]

the aero display lines are inaccurate and for rough indication only, I know this because I was talking to the guy who made them at the time, and as they are just a debug tool and not intended for use during play there are no plans to improve them.

So, timeout, aero was "debugged" using a buggy tool? By the transitive property of debugging...

FailFish

Any indication as to whether it's just the length, or also the direction is buggy? The directions are often all over the map, even for symmetrical parts, and the flight behavior of the craft seems to support what they're showing, magnitude aside. They often seem to illustrate the weird "sideways drift" tendencies of some aircraft, which sometimes can be resolved simply by reattaching the exact same parts in the exact same locations".

[Soviet03]

Okay. Well then I give up on KSP. I spent tens of hours discovering and doing my absolute best to confirm an obvious bug that IS affecting flight performance and people who have seemingly not done any testing are simply saying I'm wrong and that everything is fine. - I started reporting on this bug BEFORE I used the "debugging" models to show what I mean. Its just easier to use the models as they obviously seem to be in some way related to the issue as on aircraft where the other side works it pulls in that direction for unknown reasons.

Once again, this is only visible in situations where things get VERY sensitive particularly on large aircraft at very high altitudes.

I mean this Sal_vagar who is manipulating the nature of the bug report is making it sound as if I'm talking about the natural tendency of most aircraft to pull slightly (Up or down normally) without SAS, I TESTED THIS WITH AND WITHOUT SAS., Even extreme SAS controlled RCSs to get maximum control. You're CLEARLY misunderstanding the nature of this bug and sweeping it under the rug and I do NOT appreciate that one bit.

"This is why SAS exists, to hold craft steady, expecting craft to stay put with SAS off is unrealistic." - Which is of course why I use SAS, I'm not an idiot sitting here reporting an issue with a flawed aircraft without SAS being used ffs.

- - - Updated - - -

If people want to act like they know what they're or I'm talking about based on little to no testing not understanding the acute nature of this obvious bug then I say let them. Terrible shame and mishandling of an obvious bug but so be it, I quit KSP as this bug makes my space plane unplayable/impossible.

I find it extremely insulting that you even bring up the SAS issue given the amount of time I put into explaining the issue both here and especially on the steam forums where there is more detail. (The images I provided show SAS activated)

Never once did I say the debugging tool was accurately portraying the exact issue at hand, however it is blatantly related in someway to the odd behaviors of the type of aircraft I've mentioned in sensitive situations. - This is obviously a game breaking issue in terms of space planes to a certain degree.

PS: If you want the .craft file send me an Email at [email protected] I can send it to you via that. Not interested in paying for a dropbox service.

PPS: Claw once again I'm not seeing the same issue in your latest pic, keep in mind the lines act strangely. For testing we need to specifically stick to horizontally placed parts. Show me using MK1 parts where one side blatantly isn't producing the Cyan line.

Edited August 5, 2015 by Soviet03

[sal_vager]

Just what is the bug here? No one has actually shown an issue other than the aero display lines which is not really a bug, and the aero values in the action menu clearly show there's no discrepancy.

So what exactly are you trying to show here? That planes don't fly straight? That's old and unfixable as I said, that some designs don't fly well? Aero was remade for 1.0 and some kinds of design just won't work anymore.

Planes made with rocket tanks are flying fine, Claw and myself have tested the one posted here and everyone playing career will make a plane with a rocket fuel tank until they unlock the jet fuel tank, and all those planes fly as well or as badly as they were designed.

My own plane above was tested with aero tanks and a mix of both, and there's no real difference.

Also, this is the support forum, it's for support, bugs go on the tracker, and bugs need to clearly show unintended behavior, reproduction steps and affect the game in some way.

Here's the link to an example bug report, this is the kind of thing we need but "bugs" like this aren't likely to be fixed when they don't impact the game, the aero overlay is more likely to simply be removed as it is not required outside of testing at all, it's known to be inaccurate so mostly it was ignored, it just looks fancy.

If you guys have a reproducible issue that affects the game that's one thing, but so far all you seem to have is a crude debug telltale which you're proudly pointing to as if it was a game breaking issue.

There is no bug here, sorry, you're over-analyzing a non-issue.

And dropbox is free.

Edited August 5, 2015 by sal_vager

[Soviet03]

Sal-Vager. if the OP here didn't explain it to you please see my link to the steam forum where I go into MUCH more detail. - I tried to give most of that here but I was under SEVERE pressure to make this OP very short and was meant to be easily understandable.

To those interested here is another pic (Which was in the OP btw) showing a good aircraft to test this (visual) side of the bug. http://steamcommunity.com/sharedfiles/filedetails/?id=484727876

OMG sal is lecturing me about 1.0 changes and old aircraft. Alright he thinks I'm just an idiot. Ignoring him. What can you do..

SAL I provided all the required information on what the bug is, and how to reproduce it. Just because you live in la-la land doesn't have anything to do with the real world. Once again, this bug obviously affects the game.

PS: And dropbox says right on their website buy now or try a 30 day free trail.

- - - Updated - - -

Edited August 5, 2015 by Soviet03

[sal_vager]

Again all you show is the aero overlay, what is the actual issue to aircraft in flight here?

All anyone has said so far is that planes can pull to the side at high speed, this can happen for several reasons non of which are to do with the aero overlay, there's a lot of drag and instability around mach 1, the values for this are in the physics.cfg, also the center of mass will move as fuel is used, blunt designs are also inherently unstable, but these are by design.

Edited August 5, 2015 by sal_vager

[Soviet03]

Again all you show is the aero overlay, what is the actual issue to aircraft in flight here?

Here is a quote right from the OP in case you missed it "causing the aircraft to become unstable and pull to one side which can even lead to catastrophic failure during high altitude flight"

And here is one from the steam discussion.

"However it comes with difficulty. It slightly pulls to the right, up a little too while It tries to roll over. At high speed high altitude it can and HAS pulled itself all the way over to the right causing a spin out (No, I'm not running into an issue with engine airflow) You can fight it somewhat with yaw control, during the entire assent you have to fight it calmly until you hit time for orbital injection where its a beast to be dealt with. Basically, not operational."

[sal_vager]

Soviet03, some craft will do this, others won't and craft that do this can usually be fixed, craft can be unstable in KSP now.

But you and others are pointing to the aero overlay and claiming this is a bug in the flight system, not all planes will fly anymore, so they need to be redesigned.

You can put your craft file on hastebin.com

[Soviet03]

Its like you think I play with the overlay? As I said before I got annoyed with this issue and started a discussion before even thinking of pulling up the overlay - When I did I noticed something quite strange which seems to have something to do with the issue I'm experiencing this I figured it was a good way to show people what I mean. - I can't really show the unstable flight with images and I've not recorded any video.

- - - Updated - - -

Soviet03, some craft will do this, others won't and craft that do this can usually be fixed, craft can be unstable in KSP now.

But you and others are pointing to the aero overlay and claiming this is a bug in the flight system, not all planes will fly anymore, so they need to be redesigned.

You can put your craft file on hastebin.com

STOP that crap now! - All of these aircraft were made on the new version, before then I used FAR. I've taken piloting lessons in real life. I'm not an idiot and you shouldn't be either.

That is a BLATANT excuse to try and push the blame off the bug and into unknowns no one will test whereas I've had people reproduce the issue I'm explaining which does NOT pertain to an issue in the overlay but flight performance. If you think these aircraft would behave how they are right now in reality you're simply mistaken. You simply don't have any idea of the issue at hand, seemingly because you haven't read the OP in which I've had to post quotes down here just for you.

[sal_vager]

Post your craft Soviet03, I'll have a go at fixing it, I can't promise anything though but all my craft that were unstable were fixable eventually.

I've had plenty of planes become unstable, returning spaceplanes are the worst as they tend to have used the most fuel, so they try to fly backwards if you're not careful, we were supposed to get a stability overlay in the SPH, very different to the debug lines, which would show an issue but it was put back.

You can get a similar effect though by tilting the plane up and down in the SPH with the CoM and CoL indicators on, and try with no fuel, if the CoL move in front of the CoM when the plane is pitched up or down you have an inherently unstable design.

[Soviet03]

Post your craft Soviet03, I'll have a go at fixing it, I can't promise anything though but all my craft that were unstable were fixable eventually.

I've had plenty of planes become unstable, returning spaceplanes are the worst as they tent to have used the most fuel, so they try to fly backwards if you're not careful, we were supposed to get a stability overlay in the SPH, very different to the debug lines, which would show an issue but it was put back.

You can get a similar effect though by tilting the plane up and down in the SPH with the CoM and CoL indicators on, and try with no fuel, if the CoL move in front of the CoM when the plane is pitched up or down you have an inherently unstable design.

That's because as "your" craft consume fuel, the center of mass moves behind or too near the center of lifting causing it to become unstable, if its behind the center of lift of course its going to re-enter backwards. That's physics for you. - DUH

I test all possibly fuel displacement possibilities before flight. Again, I'm not an idiot despite what you'd like to think.

PS: I can upload it's text content to Hastebin but this particular aircraft uses mods which no doubt you'd love to dismiss based off that so I'd have to make a stock version that's comparable.

Edited August 5, 2015 by Soviet03

[sal_vager]

If you posted your craft others could verify this by the way, you say you have an issue here but you have not been able to show it yet so we don't know if the craft is bending due to excess drag at high speed or what's going on.

[Red Iron Crown]

Soviet03, no one is calling you an idiot. People are genuinely trying to help you here and get to the bottom of what is happening, you are shouting at them in return. If you want people to reproduce your issue then share your craft file and the reproduction steps (as explicitly as possible).

Edited August 5, 2015 by Red Iron Crown

[sal_vager]

I am happy to install the addon Soviet03.

[Soviet03]

PS: Alright I'll upload the same old craft and give you a mod list. Saves me time.

- - - Updated - - -

http://hastebin.com/babomucese.py

I think it's just these 3 mods let me know if it doesn't work.

KW rocketry, SpaceY Heavy lifters, Fuel tanks plus

Before you say it, without cargo (as the version i sent you) The small fuel tank all the way in the front is intended to be locked so the center of mass remains beyond the center of lift. - Not that you'll get to that point before things start to go wrong probably. {When i fly it, I do manually manage the fuel distribution too, which normally involves pushing it forward however sometimes I push it back for more mobility) - You can drop the external tank right after takeoff, its actually just there to assist during takeoff.

[sal_vager]

Thank you Soviet03, I will look at this craft now.

[WinkAllKerb'']

hum ... it's hot in here xDr ... anyway ... i finnally made this craft just per curiosity, wich is symetric but assembled an assymetric way.

then it appear to have a flight impact, and that the overlay is linked to flights physics results.

(As with this craft as you start to pitch, right after auto take off without the need for any direction input, it spin, apparently due to one part only with a different light blue vector orient, while the said part is totally symetrically placed in the end but not attached symetrically at first)

craft file:

https://drive.google.com/file/d/0B5JHmZea7s91MXFhazV1VmNPN3c/view?usp=sharing

Javascript is disabled. View full album

full gallery with assembling reproduce step & comments, (a few extra img at album end that can't be deleted from it after upload {24 to 29})

EDIT:

COM and COL to each other with an assymetric built plane (left) and a symetric built plane (right).

seem it has no impact at this point not sure may be it might be usefull to apply some physics calculation transformations workaround somewhere & between in // with the unity issue thing.

Edited August 6, 2015 by WinkAllKerb''
album added & extra testing

[Signo]

Wow, things got re entry hot around here. Just stopped by to say "thank you Claw" for the testing on my plane.

Cheers.

[Manwith Noname]

...the only "bug" reported is the mismatched lines, which do not matter.

You are going out of your way to prove a bug that isn't there, I'll say what Claw said but in simpler terms, There is nothing to be learned from the length of the aero overlay lines, they are not accurate and were never intended to be.

This is indeed what I have come to accept over the first couple of pages as I have not flown a craft that behaves in a manner that reflects the imbalance shown. I think the problem that needs to be addressed is, as a player, you are not aware of this fact and people do use the overlay to inspect the dynamic forces upon their craft, rightly or wrongly, people will use that data in their fault finding and design considerations.

So, in my humble opinion, it either needs to work accurately (as in, actually represent the data being used by the aero physics), be removed from the game or some way needs to be found to communicate to the player that these are just pretty lines that can backfire on you in terms of fault finding design issues.

What I am curious about, how did you get that data to show in the right click menu? Is there a way to represent that data visually instead of the current overlay system?

[Soviet03]

After some thinking, and further tests I believe I may have overlooked 1 major design flaw in my aircraft which leads me to believe there is no bug present other than the false readings from the debugging menu (Which i did rely on, making me confident there was a bug, In fact if I never had access to the debug perhaps I would have realized my mistake much earlier on)

That being? I had basically created a flying wing with VERY little YAW stability. Meaning the aircraft especially under acute conditions simply didn't have the YAW authority to keep itself stable. [A matter of aerodynamic physics I'm aware of, but sadly one I overlooked after getting giddy when I found the debug menu and relied on that, making me think it had something to do with the flight performance especially when it only seems to apply to some parts and not others] Also, with a flying wing, I neglected to make sure the only roll control would be on the edge of the wing, instead with my middle control surface also rolling[and pitching] it could often create a certain disbalance in pitch {As in certain conditions the roll, when only applied to one wing is also creating [downward]pitch automatically, this could happen on my craft as the surfaces don't always end up being equal opposites when the control surface in question also determines pitch} - This means that theoretically the aircraft would pull either left or right during the same flight depending on certain conditions however my aircraft being so bulky and slow to maneuver never got the chance to experience that before failure.

^ I discovered that with a smaller more nimble test aircraft, put more vertical surfaces on and problem solved as expected.

TL;DR: This started with a mistake on my part which I overlooked after finding and sadly relying on the debug information to be accurate which once I saw it made me think I was looking at visual confirmation of a bug.

Shm, stupid debug menu making me look like an ass

Edited August 5, 2015 by Soviet03

[sal_vager]

Soviet03, no you're not an ass, you're passionate and I can respect that.

Manwith Noname, if you need accurate numbers enable the aero info in the action menu, then alt+click all your parts that you want to see data on in flight, it doesn't work for all parts as they need to have an action menu, but it will show numbers instead of a line with no gauge to measure it by.