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

[Shad0wCatcher]

If you think that's correct and how things should be I won't pester you to look deeper into it.

Looking at the models though the relative change between the two is identical. The structural fairing adapter is going from a 5 meter diameter to 3.75. The fuel adapter is going from 3.75 to 2.5. Both are a 1.25 meter diameter drop.

I think I may have figured out their use anyhow (pseudo-fairing adapter...used in place of the actual fairing adapters) and I more reasonably understand what you're meaning; the taper between the two is affecting the fuel adapter more due to the overall length of the taper (combined) and slowed airflow from from the fairing adapter causing more friction (and drag) on the fuel adapter. Unless I'm completely off-base, which is entirely possible.

The reason behind that design is that its payload was wide but not particularly heavy. Four Probe lander/return craft were crammed inside. I used a 3.75 fairing and was trying to keep my TWR / DV budget somewhat reasonable. I didn't want a 4+ TWR upper stage motor with 3-4k DV ripping my rocket apart when its getting dumped at AP anyway. (Wasn't using that motor and the payload was just so it had something. The actual payload was around 15-17 tons.

[roxedboxer]

So I'd be willing to bet this has been asked already, but I simply don't want to wade through a few hundred pages of comments. How compatible with procedural fairings is FAR?

Edited December 28, 2013 by roxedboxer

[ferram4]

@Hodo: I guess I can look into that. It'll be a bit of a pain to set up though.

@BC000001: Yep, that's correct. Sudden drop-offs in the object's diameter generally create quite a bit of drag, and a smoother tapering can lead to a less draggy configuration.

@Shad0wCatcher: I meant percent change, so that would mean that the fairing adapter has a taper ratio of 0.75 but the fuel adapter has a taper ratio of 0.6666..., and the lower that number gets the greater the drag on the part.

@roxedboxer: It works fine. This is actually answered in the first post of the Procedural Fairings thread.

[Hodo]

@Hodo: I guess I can look into that. It'll be a bit of a pain to set up though.

No rush, just a request. Because I know there are quite a few people out there like me who understand the basics of aerodynamics but not that familiar with it.

[jrandom]

So I'd be willing to bet this has been asked already, but I simply don't want to wade through a few hundred pages of comments. How compatible with procedural fairings is FAR?

Procedural Fairings has been specifically crafted to work with FAR. They're indispensable.

[Roxette]

I've not seen mention of it here (and I'm not scouring 2630 posts) and I'm not even going to start on what's wrong with spaceport, but if there's interest in compiling a moderate collection of FAR-compatible air- and space- planes (rockets are really not that hard, people) I think it would be a good idea, and I'm prepared to help with that, although I don't have the time to make it a one-man project.

[jrandom]

I dunno, I've always felt that .craft collections are exactly opposite to the spirit of Kerbal. What's useful is basic design rules-of-thumb so you kind of know what you're doing during construction.

[Donziboy2]

ferram4

If we remove the FARWingAerodynamicModel module from B9 parts and weld several together into a wing will FAR still recognize the entire lift surface?

[a.g.]

Wings must be explicitly declared with all the right parameters - it's only the plain drag-only parts that magically just work (more or less).

[roxedboxer]

Really now? That is fantastic news! I'll definitely have to gvive FAR a try.

[Taki117]

Question about Aerobraking: I'm on my way to Duna and planning an aerobrake for the first time with FAR, and I was curious how it affects said procedure?

[AndreyATGB]

I haven't done it with the stock game, just in RSS. If your craft is complex it likely means you won't be able to keep it poiting retrograde depending on its shape. If it's large you might not notice much difference with FAR but if it's small and thin you're likely gonna need to go pretty deep. It's not really that different, you're just gonna need to try and reload 2-3 times and you're gonna get it pretty quickly.

[Picard]

hey guys and Ferram4, i have an small issue with FAR. I noticed that when using the base game the control surfaces move between their extremes slower. The effect of this was that when using SAS the craft tends to not get the wobbles between pitch and roll. Now with FAR installed (which has been a 'must have' for my games for a long time) the control surfaces react with a faster speed akin to previous iterations of KSP. Thus when using FAR i tend to get mass amounts of pitch and roll instabilities as the sas cause the entire craft to shake.

Flies perfectly when sas is disabled, and i love the new deflection mechanics for the fuselage parts, i just find the control surface speed to cause too much wobble.

The speed the stock game seems to move its control surfaces at is the same as the FAR speed when fine controls (CAPS) is enabled, however when sas is also enabled the control surfaces move with their maximum speed. Perhaps this could be a bug fix?

[Tharios]

hey guys and Ferram4, i have an small issue with FAR. I noticed that when using the base game the control surfaces move between their extremes slower. The effect of this was that when using SAS the craft tends to not get the wobbles between pitch and roll. Now with FAR installed (which has been a 'must have' for my games for a long time) the control surfaces react with a faster speed akin to previous iterations of KSP. Thus when using FAR i tend to get mass amounts of pitch and roll instabilities as the sas cause the entire craft to shake.

Flies perfectly when sas is disabled, and i love the new deflection mechanics for the fuselage parts, i just find the control surface speed to cause too much wobble.

The speed the stock game seems to move its control surfaces at is the same as the FAR speed when fine controls (CAPS) is enabled, however when sas is also enabled the control surfaces move with their maximum speed. Perhaps this could be a bug fix?

Ferram sped up the reaction time of control surfaces. So now you can do more with fewer control surfaces. Use the tweakables in .23 to designate large flaps for pitch only, and just a couple of small flaps for roll control. Keep the roll flaps in toward the body if the wobble is still a problem.

Your design is fine, it's just the changed parameters of the game necessitate changing your strategy...ie, your flap usage and positioning.

[Picard]

thx for quick response. Yeh i always dedicate certain control surfaces to a single task. The thing is that i don't want to have to reduce the total movement of the control surface to reduce wobble, and the stock speed is perfect for reducing the sas instability.

if it were possible to alter the degree of movement in flight through action groups or something then that'd be cool, or have the ability to choose the reaction time.

ahh well.

[ferram4]

@Picard: You can go into the config.xml file in FerramAerospaceResearch/Plugins/PluginData and increase the control surface time constant parameter to a higher number if you want slower acting control surfaces. I've found that higher values (with more control delay) tend to cause SAS to freak out more than lower delays. Regardless, whenever the next version comes out it control surfaces will be set to deflect about as slow as the stock ones.

[Brian Wiens]

Hey again Ferram. I have a question for you. Does FAR model the Coandă effect? If you don't know what it is, it's the tendency of a fluid jet to be attracted to a nearby surface. In simple terms, the exhaust gas from a jet engine is blown over the wings upper surfaces to boost lift. Does FAR model this because I am not sure and it would be cool to make some STOL aircraft like the An-72 Coaler and C-17 Globemaster.

[ferram4]

I wish I could, but I think that would be a pain to try and model. I'll add it to my list of things to try when I go and recode everything though.

[Brian Wiens]

I wish I could, but I think that would be a pain to try and model. I'll add it to my list of things to try when I go and recode everything though.

Okay, cool. Give it a try and if it's a pain to code and make work, then don't sweat it. I can always add SRB's to decrease take-off time.

[jrandom]

Anyone happen to know what causes uneven intake air distribution? I've got two raidal intakes, one on each side. To them is connected: fuel tank -> fuselage -> engine. In the middle is the third engine, which gets the least air, and the two side engines get uneven air. Fuel lines run from the side tanks to the central fuselage.

Edited December 29, 2013 by jrandom

[AndreyATGB]

How did you get the Air and SAS force to show?

[jrandom]

B9 Aerospace engines show their air gauges. It might possibly add the SAS indicator as well.

[lumpman2]

I've tried to do a gravity turn a few times already, but I can't seem to get down exactly what I should be doing. I always try to keep a low angle of attack, but my apoapsis is already at about 60km when I've only turned over about 10-20 degrees. I'm not sure what I'm doing wrong, because no matter how hard I turn sideways (the air doesn't really let me get an AoA of more than 5 degrees), the prograde marker doesn't want to move any more than it always does.

[jrandom]

Launch with a TWR of 1.2 (throttle down if you have to) and start your gravity turn somewhere 'round 100m/s speed. A profile that's worked for me is to hit 45 degrees of tilt by 10km and 85-90 degrees of tilt by 30km.

[AbeS]

Start your turn earlier, reduce your TWR. And I think you are using the non-gimbaling plus SRBs, the pod's torque and the control surfaces may not be enough with that acceleration.