Jump to content

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


ferram4

Recommended Posts

Hi Ferram4, I'm trying to dissect the basicaDragModel to understand it a little better...

cosAngleCutoff //what's this? stall angle?

majorMinorAxisRation //ratio of longest dimension and shortest dimension relative to foward direction of the part? long thin parts would be close to 1; flat wide parts would be close to 0?

taperCrossSectionAreaRation // for conical shapes? cylinder would have ratio of 1? sharper cones would have close to 0?

ignoreAnim //Recalculates drag values if animation changes the part's shape?

the curve keys

1 //forward

0 //sideways

-1 //backward

what's the 2nd number? multiplier? how does positive/negative affect the drag?

whats diffference between ClViscous and ClPotential?

CmCurve applies to rotation in all axis? or just pitch?

Thanks!

Link to comment
Share on other sites

FIXED

My Problem is fixed thanks for looking into it. Thanks again for your work on FAR it's fantastic.

The problem was the cockpit I was using it's been updated to work with the new version of FAR. Now my aircraft is stable and is accelerating as it should.

Mk.2 Lightning

Cockpit for B9 Aerospace

v1.3

- Fixed drag issue for FAR v0.14.3.x

http://forum.kerbalspaceprogram.com/threads/96766-Mk2-Lightning-Cockpit-for-B9-Aerospace-v1-3

CEF54A20DE4E7AFF5FCEFB80B1EB27AC1565AB00

Edited by LMA
Link to comment
Share on other sites

@DaMichel: I saw it, I just haven't merged yet.

I have seen that it is in now. Thanks. This means FAR should now change all stock IVA speed gauges, too.

I didn't find an answer to my question and it's been buried. Are there any hot keys for FAR? I'd like to be able to toggle the FAR assists while I'm flying, but it requires me to take my hand off the joystick to do it. If so, where can I find them/what are they? And if not, are there any plans to do something of this sort? I know the assists were meant for keyboard users mostly, but the wing leveler is (usually) really useful during take off, landing and just flying a really far distance.

I don't think there are hot keys. At least i never head of it or happen so see something in the code. It would be nice to have action groups for the assistants, i guess. Add my vote!

Btw. here is a glider i made. It is quite amazing because it matches the performance of some real world glider quite closely. My version is much heavier due to stock parts but that is a non issue because wing loading and L/D ratio are right. Takeoff goes the Kerbal way with a bunch of separatrons :D And it can stay in the air for quite long. I made the trip to the island airport starting from 1 km altitude above KSC!

CIQ7O46.jpg

Edited by DaMichel
Link to comment
Share on other sites

Is there any way to delete the code that stops the thing from turning off on 64x?? Idc if It crashes on revert, i just want it to launch!

Certainly there is, but you'll have to find it yourself and recompile the dll... as Ferram said... i'm not coder at all myself, just saving you the read...

Link to comment
Share on other sites

But how? I examined pictures of it's control surfaces and didn't understand how reproduce it. Any control surfaces at the end of wings will be useless at this angle because of stall, maybe with canards but it do not have canadrs.

Link to comment
Share on other sites

Maybe stall is wrong word but it's not work for me, I could not to make anything with such wings keep AoA more then ~20 regardless of deflection angle of control surfaces and CoL position, what's the trick?

Edited by zzz
Link to comment
Share on other sites

Control surfaces are not useless when stalled. They are just less effective.

There's also the fact that at those Mach numbers, "stalled" isn't really a concept that makes much sense. It will fly fine.

Fly? It fell, with style... ;)

Link to comment
Share on other sites

Maybe stall is wrong word but it's not work for me, I could not to make anything with such wings keep AoA more then ~20 regardless of deflection angle of control surfaces and CoL position, what's the trick?

Do have DCA enabled? If so you might want to increase the speed constant or disable it entirely. I find that the default setting often decreases or eliminates my pitch authority at high speeds.

Edited by blowfish
Link to comment
Share on other sites

Do have DCA enabled? .

Nope.

Well, I will ask another way - do anyone have any craft capable to keep AoA 45 at Mach 12-15 without canards, cheaty gyro and RCS?

Just to take a look at CoL - CoM - control surfaces scheme

Edited by zzz
Link to comment
Share on other sites

Nope.

Well, I will ask another way - do anyone have any craft capable to keep AoA 45 at Mach 10-12 without canards, cheaty gyro and RCS?

I can't say that I happen to have such a craft in my KSP install, but the requirements you've posted remind me a bit of a few craft I used in Orbiter 2010. I can't say how its aerodynamic model compares to FAR if it does at all, but from what I recall, at those speeds and angles of attack, the aerodynamic surfaces were almost completely ineffective.

Eventually, after comments on how much propellant the RCS system consumed trying to maintain the correct re-entry profile, the craft were updated with a special fuel pumping system that dynamically altered that craft's centre of mass by pumping fuel aft and forward to maintain a given angle of attack.

It may be possible in KSP to balance a craft in such a way that you can pump fuel into a certain combination of tanks that will allow a plane to maintain a given angle of attack at a certain airspeed and pressure, but the slightest variation would undoubtedly send the craft into a dangerous spin.

As an afterthought, you could consider the "cheaty gyros" to stand in for the extra mass such a pumping system and the required avionics would take up.

Link to comment
Share on other sites

I think I've found the issue I had in 0.14.1 and 0.13, where my wings would randomly stall, usually causing a pull to the right, during takeoff (it never got further than that because of the stalling..). As it turns out, Kerbin-Side isn't playing well with FAR. All I know is, I was solely using Kerman Lake as my launch site, and I started doing that in 0.25 and had the same issue again. When I spawn at KSC, the issue is not present. I've tested it extensively now. Is there any chance of a fix for this in the future?

Link to comment
Share on other sites

Nope.

Well, I will ask another way - do anyone have any craft capable to keep AoA 45 at Mach 12-15 without canards, cheaty gyro and RCS?

Just to take a look at CoL - CoM - control surfaces scheme

the space shuttle didn't really fly during reentry, it's reentry configuration was basically the large flat underside with balanced forces. it fell with style. once the atmosphere was thick enough and speeds slow enough, it started to fly, but that was well into the atmosphere.

Early in reentry, the orbiter's orientation is controlled by the aft steering jets, part of the reaction control system. But during descent, the vehicle flies less like a spacecraft and more like an aircraft. Its aerosurfaces -- the wing flaps and rudder -- gradually become active as air pressure builds. As those surfaces become usable, the steering jets turn off automatically.

Link to comment
Share on other sites

@Volt: I can look into that, but it might not be something I can fix on my end. If they're teleporting you from the KSC to those launch sites during the Start() methods, then there will be serious problems, and there's not much I can do about that. They'll be effectively putting half the aircraft in one location and half in another for all the wing interaction effects.

Link to comment
Share on other sites

Yeah... I can see why that would be a problem. I've posted on AlphaAsh's thread as well, so I'll see what he says. I hope it can get sorted, because the two mod concepts do really lend themselves to being combined.

Link to comment
Share on other sites

the space shuttle didn't really fly during reentry, it's reentry configuration was basically the large flat underside with balanced forces. it fell with style. once the atmosphere was thick enough and speeds slow enough, it started to fly, but that was well into the atmosphere.

I not said it necessary fly or how ot called, but it object of aerodynamic and gravitational forces anyway, I asked how it made it. If it somehow shift mass to keep balance in needed position at different mach this the trick and answer.

Edited by zzz
Link to comment
Share on other sites

Sounds like you need less thrust.

zzz: make your craft, in the SPH, exactly in the condition it will be in reentry. Tweak the fuels, etc. Then go to FAR's simulation, and sweep AoA for starting at like 40, and ending at 45, with pitch at 1.0. See if the Cm line crosses the X axis. If it does, then you can maintain that AoA; if not, you'll have to tweak (more control surfaces, move CoM, etc).

Link to comment
Share on other sites

Okay, I need help with gravity turns. I know the 'turn slowly at 100 m/s, tilt over, follow prograde, use gimballing not SAS' I just don't understand how to do it with all the mach effects. I've done it with NEAR, but I still can't figure out FAR and the mach stuff

What exactly is the problem? A gradual tilt where you keep your AoA below 10° at all times should see you up without difficulty.

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...