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

NathanKell · January 19, 2014

Known issue: typo in the cfg.

http://forum.kerbalspaceprogram.com/threads/20451-0-23-Ferram-Aerospace-Research-v0-12-5-2-Aero-Fixes-For-Planes-Rockets-1-7-14?p=904850&viewfull=1#post904850

Sauron · January 19, 2014

I've put drag chutes on it now and that's looking promising--never really had the need for them before.

But I interrupt my struggles with a bug (maybe?) on reloading a quicksave and reentering kerbin's atmosphere I'm getting outrageous--as in actually impossible--terminal velocities. On the order of 70 m/s at 40000 m. Is this a known bug? If not, I'll see if I can replicate it tomorrow.

ferram4 · January 19, 2014

That's an issue with older versions of FAR; make sure you're running v0.12.5.2.

RoboRay · January 19, 2014

...On that note, an Edwards AFB-like site in ksp would be awesome!

A flat basin over in the desert with runway markings would be pretty neat.

zzz · January 19, 2014

When I tested how reentry raycasing work, to be sure I can to hide behind shield, I noticed strange thing with my custom model, looks like it(3,375 meters sphere) produce over thousand times more drag then 5meters shield and almost 100 times more drag then 3,75 tank. It can not matter much, because it intended to use in space anyway and I will install it by tricky way, and even handy - because can be as stabiliser and brake durning reentry but it seems wrong to me. Maybe it's because I use unity sphere collider, I even don't know maybe it's bad to use it, usually I use custom mesh. Or maybe because there several(4) small(and one big on top) attach points on it. How can i adjust something to make it more correct?

Edited January 19, 2014 by zzz

ferram4 · January 19, 2014

Well, odds are it should make more drag; it's not like spheres are really all that aerodynamic. That said, there are still some things wrong because FAR doesn't know how to handle parts that can't be approximated as conical frustums, and I'm not planning on adding support for more complicated shapes because it risks adding very nasty issues if someone else comes up with a more convoluted shape. FAR also doesn't account for local changes in dynamic pressure yet, which would make using them as airbrakes behind a heat shield impossible.

I'll look into adding a bit of code to override using attachNodes for drag, and then the only solution would be manually setting the drag parameters.

zzz · January 19, 2014

I thought spheres must produce less drag then blunt cylinders, just from common sense, it's, you know, more smooth somehow. And I asked for some config fix, not changes in your model. But if this is normal, well, Ok then, I'm not really good in physics.

which would make using them as airbrakes behind a heat shield impossible.

Well, currently it's behind and is produce lot of drag, then why not?

And if you there, sorry for somehow unrelated, but you know how this raycasting in ksp work - what kind of "heat shadow"(I don't know how to call it correctly) shield is produce? Is it parallel from the edge or angled outwards or maybe inwards? By which angle(approximately)? Or all this works differently than I expect?

And sorry for so much questions, but you also creator of KJR (You great person actually), so you know how it work from inside - this balls tend to pop out while radially attached if not struted, I'm Ok with it, but feels like it tends more then other things, what possible wrong I could made with it?

Edited January 19, 2014 by zzz

ferram4 · January 19, 2014

Spheres produce less drag than cylinders in cross flow. You've got cylinders in axial flow there, which causes the difference.

As for the stuff added in the edit, the raycasting done by deadly reentry is directly along the surface velocity vector, and it only goes from the center of the part. That means that if you get the center behind the shield no heat will be added to it.

As for the part popping off, odds are that the part's density is either higher or lower than most other parts in the game; in the first case, the joint won't be strong enough to handle the weight. In the second case the added stiffness will cause issues when floating point errors start to crop up.

Edited January 19, 2014 by ferram4

Captain_Party · January 19, 2014

Why, when I put on winglets, do my rockets roll out of control? They just roll from left to right, and I can't arrest that motion. Is it a bug?

ferram4 · January 19, 2014

Well, it depends on what level of symmetry you attached them on and how far off prograde you're taking the rocket. 3-way symmetry in particular can cause uneven lifting forces on either side of the rocket when the sweep of the fins is taken into account.

Captain_Party · January 19, 2014

I always use 4x symmetry. It literally just rolls out of control.

ferram4 · January 19, 2014

Fins aren't angled at all? Angle of attack is always less than 10 degrees? Using FAR v0.12.5.2? Picture of the rocket?

Captain_Party · January 19, 2014

Ooh... That was it. AoA was off. God I'm stupid

ferram4 · January 19, 2014

You probably managed to get the beginnings of a stall on one of the fins. Or managed to get into highly nonlinear flow regimes.

sjgold · January 19, 2014

Houston we have a problem........

So i was starting a brand new installation of KSP and updating all my mods and such, and I started a new career. Something very odd happened with a SRB/Capsule/Chute beginning launch with the velocity being fairly insane. I stripped out all the mods except FAR and tested. The SRB is getting insane velocity I took the screenshot at burnout with only FAR installed and no other mod. Please advise.

gFqm8q2

If the image does not appear the link is

http://imgur.com/gFqm8q2

Edited January 20, 2014 by sjgold

sjgold · January 20, 2014

Houston we have a problem........
So i was starting a brand new installation of KSP and updating all my mods and such, and I started a new career. Something very odd happened with a SRB/Capsule/Chute beginning launch with the velocity being fairly insane. I stripped out all the mods except FAR and tested. The SRB is getting insane velocity I took the screenshot at burnout with only FAR installed and no other mod. Please advise.
http://imgur.com/gFqm8q2

Sorry for some reason image did not show up..

gFqm8q2

AndreyATGB · January 20, 2014

That's perfectly normal. What you're flying there is essentially an arrow, it won't have much drag. The trick with FAR is to launch big and heavy stuff, that's a challenge. For comparison you need about 3600m/s dV with FAR for an orbit compared to 4500m/s in stock. Also remember that you can't suddenly turn 20 degrees at 10km, you need to start when you're traveling at 100m/s and by 40km I'm usually level.

ferram4 · January 20, 2014

@sjgold: Let's do some math, shall we?

Your vehicle is a Mk1 Pod (0.8 t), a Mk16 Parachute (0.1 t) and an RT-10 SRM (0.5 t dry, 3.7475 t gross). So burnout mass is 1.4 t; initial mass is 4.6475 t. Assuming that it spends its entire burn with sea level Isp (225s) this rocket has:

dV = Isp * g0 * ln(m0 / m1)

dV = 225s * 9.81 m/s^2 * ln(4.6475 / 1.4)

dV = 2648 m/s

So the speeds you've gotten it up to are completely reasonable, given that it actually has slight more dV due to the decreasing air pressure. I suspect you're confused because normally the atmosphere just sucks away any velocity like mad; this is not physically correct, unless Kerbin's atmosphere is actually made out of pudding. This is what is supposed to happen.

Surefoot · January 20, 2014

300 pages, let's pop the champagne How do we throw a little money at you Ferram, you extended my gameplay for maybe that many hours (that's about 300) just thanks to your mod. Still having a blast flying my various planes, space going or not. Also still *****ting bricks when aerobraking on Jool. FUN !

camlost · January 20, 2014

Hi ferram4,

How's it going with the previously proposed 'aggregate approach'? Not intending to push though. If some difficulties are encountered maybe we can discuss somewhere.

likke_A_boss · January 21, 2014

Hey Ferram,

I'm having a problem in my debug log, where it is spamming the same message over and over. Heavily modded game, but I think its coming from this.

Log:


[LOG 18:45:27.622] Stagnation Pressure Coefficient Curve Initialized
[LOG 18:45:27.622] Stagnation Pressure Curve Initialized
[LOG 18:45:27.624] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.624] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.624] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.625] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.625] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.625] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.646] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.646] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.646] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.646] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.646] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.646] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.662] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.662] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.662] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.662] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.662] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.662] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.678] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.679] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.679] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.679] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.679] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.679] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.696] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.696] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.697] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.697] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.697] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.697] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.713] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.713] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.713] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.713] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.713] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.713] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.729] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.729] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.729] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.729] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.730] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.730] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.746] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.746] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.746] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.746] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.746] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.746] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.762] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.762] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.762] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.763] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.763] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.763] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.779] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.779] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.779] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.779] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.780] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.780] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.796] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.796] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.796] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.796] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.796] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.796] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.812] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.813] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.813] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.813] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.813] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.813] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.829] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.829] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.829] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.829] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.829] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.829] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.845] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.845] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.845] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.846] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.846] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.846] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.862] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.862] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.862] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.862] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.862] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.863] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.879] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.879] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.879] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.879] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.879] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.879] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.895] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.895] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.896] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.896] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.896] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.896] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.912] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.912] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.913] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.913] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.913] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.913] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.929] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.929] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.929] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.929] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.929] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.929] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.945] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.945] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.945] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.945] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.946] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.946] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.962] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.963] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.963] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.963] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.963] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.963] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.979] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.979] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.979] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.979] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.979] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.979] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.996] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.996] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.996] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:27.996] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.996] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:27.996] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.013] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.013] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.013] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.013] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.013] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.013] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.029] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.029] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.029] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.029] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.030] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.030] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.046] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.046] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.046] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.046] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.046] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.046] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.062] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.062] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.062] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.062] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.063] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.063] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.079] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.079] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.079] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.079] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.079] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.079] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.096] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.096] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.096] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.096] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.096] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.096] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.112] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.113] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.113] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.113] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.113] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.113] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.129] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.129] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.129] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.129] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.129] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.130] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.145] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.145] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.145] FAR Error: Aerodynamic force = NaN

at roverBody(Clone)
[LOG 18:45:28.146] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.146] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)
[LOG 18:45:28.146] FAR Error: Aerodynamic force = NaN

at trussPiece1x(Clone)

Here is the craft:

Begins right when the first wings are placed.

NOTE:That isn't the entire log. The log is about 7x longer with the same message, but it wouldn't fit.

ferram4 · January 21, 2014

@Surefoot: I keep meaning to set up something like that, but I never get around to it.

@camlost: I've got a prototype bit of code that will calculate the cross-sectional area of a bunch of parts as a function of body station, but it only works for purely convex cross-sections. I need to extend it to concave sections, and then properly account for hollow sections. And then add code to figure out how to divide up the vehicle into various bodies so that their properties can be calculated, since a pure aggregate approach will swallow the entire CPU whole and demand more.

Once that's done I need to figure out how to handle rebuilding the cross-section map when staging occurs, especially if the body should be modeled as being in a completely different orientation.

It's going, but slowly, since I'm working on other stuff as well. No serious issues yet, but I suspect those will crop up once I start to take the cross-section map and send that to another thread to calculate aerodynamic parameters; I've never done multithreading before.

@likke_A_Boss: Bug in an earlier version of FAR; update and it will be fixed.

lipatden · January 21, 2014

Houston we have a problem........
The SRB is getting insane velocity I took the screenshot at burnout with only FAR installed and no other mod. Please advise.
http://imgur.com/gFqm8q2
That's perfectly normal. What you're flying there is essentially an arrow, it won't have much drag.

This makes perfect sense. FAR rewards you for doing good design with clean lines and low Cd (Drag Coefficient), as well as pointing the pointy end towards space. Stock only considers mass when making drag calculations for everything except aero surfaces (wings), so unless you've got wings there's no penalty for pointing the whole thing sideways.

You've got an immense TWR with that little build, so no surprise you've got both insane altitude and high enough speed to start seeing compression effects. Go baby Go!

DaMichel · January 21, 2014

Hi Ferram,

what is going on with the CoL here?

P.S. i should add: when i had the adapter + heatshield, i got crazy drag values like 90 kN on the adapter just after liftoff going at about 100m/s.

Edited January 21, 2014 by DaMichel

rhoark · January 21, 2014

Just wondering if anyone's ever put together a guide for the charts and graphs. (Even just a legend of full names for the greek-letter variables would enable Googling for more information)

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

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