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

[SkyHook]

Yeah... I download the ferram correctly but I dont get the FAR Flight System when I launch... please help

Apple jacks where is you KSP installed? For best results, DO NOT install it in C:/ Program Files, install it elsewhere.

BTW anyone notice how cargo bays and FAR simply don't mix? If the root of any wing that I attach to a cargo bay is touching said cargo bay, the then wing is considered to be shielded. This causes a large reduction in drag, and causes inaccurate aerodynamics IIRC. Can anyone shed some light on a possible solution?

Edited July 28, 2013 by SkyHook

[SpaceRodent]

Does this mod change EVERY 'Parts' folder, or just the folder in Squad? I installed it and enjoyed it but not ready for it, so I uninstalled it. I did back up my Squad 'Parts' folder, and put the backup back in when I uninstalled FAR. But now I am concerned that 'Parts' folders in the GameData mods folders are changed because of FAR, and I will have to reinstall every mod to get it back to normal. Is that true, or does it just change the stock parts?

[SkyHook]

Does this mod change EVERY 'Parts' folder, or just the folder in Squad? I installed it and enjoyed it but not ready for it, so I uninstalled it. I did back up my Squad 'Parts' folder, and put the backup back in when I uninstalled FAR. But now I am concerned that 'Parts' folders in the GameData mods folders are changed because of FAR, and I will have to reinstall every mod to get it back to normal. Is that true, or does it just change the stock parts?

AFAIK, the pack uses module manager, so all of you parts should return to normal after uninstalling. Hope you give it another try though, FAR really IS a killer app for any aviator.

[0bj4ct7]

Hi,

when i build larger rockets with Ferram installed, they often start to wobble to the point of breaking. I always make sure they're aerodynamic, wobbling may appear if even if they're perfectly symmetrical.

Wobbling is often strongest with the first stage (often worst with boosters) when rocket reaches ~ 150+ m/s.

MechJeb of course just makes it worse but problem also exists with standard .21.1 SAS. Aforementioned rockets fly normally without this mod. I've tried adding TONS of control surfaces and winglets, didn't really help.

Am i building wrong or are there specific thing yo need to avoid/do in ferram?

[taniwha]

It's actually the winglets and control surfaces making things worse because you're adding even more torque to your wet spaghetti. The solution is to strut your in-line tanks to each other. I've found that even just 4x symmetry on a set of struts from the tank above to the tank below to be sufficient. place the strut near the bottom of the upper tank such that it just goes normal (as you move up the tank), then place the end a similar distance below the top of the lower tank. For strengthening separators, use cubic octagonal struts^Wtrusses on the tanks on either side of the separator and strut the cubes together. The delta-v saved from the reduced steering losses will outweigh the drag of the cubes.

[Divided by Zero]

Surprised no one has ever brought this up, but the all new spaceplane friendly SAS still doesn't work with FAR. At all. It either randomly oscillates up and down or just does nothing. And the FAR yaw damper, wing leveler etc. have never worked for me.

[longhornchris]

Surprised no one has ever brought this up, but the all new spaceplane friendly SAS still doesn't work with FAR. At all. It either randomly oscillates up and down or just does nothing. And the FAR yaw damper, wing leveler etc. have never worked for me.

I've found that it works fairly well at mid-to-high altitudes, but causes issues in areas where my stability is low and my control authority is high. Specifically, I can't use it to hold a climb rate below 10km at any speed, but it works well once I'm above 15km and leveling off for my acceleration phase. I use it to keep the trim adjusted so I can get to Mach 5 and make the most of my jets before climb out. It also works well on the rocket-powered escape - I can set my climb angle and let it go.

What SAS definitely sucks at is understanding if there is a stall - so if you are stalling out SAS is only going to make it worse my trying to put on more control after your control authority is gone.

[Divided by Zero]

I've found that it works fairly well at mid-to-high altitudes, but causes issues in areas where my stability is low and my control authority is high. Specifically, I can't use it to hold a climb rate below 10km at any speed, but it works well once I'm above 15km and leveling off for my acceleration phase. I use it to keep the trim adjusted so I can get to Mach 5 and make the most of my jets before climb out. It also works well on the rocket-powered escape - I can set my climb angle and let it go.

What SAS definitely sucks at is understanding if there is a stall - so if you are stalling out SAS is only going to make it worse my trying to put on more control after your control authority is gone.

Interesting. I've never tried it at high altitudes, I just give up and end up using all manual control. Don't know what I'd do if I wasn't using a joystick.

[longhornchris]

@Ferram:

I'm trying to work out how to use the control surfaces as air brakes. Here's the behavior I'm getting: When I set a surface to brake it activates when I hit the 'B' key to the max deflection. Nothing happens when I bind the 'raise/lower' to action groups, nor do I see 'raise/lower' in the action box when in flight.

What I'd like (if possible) is to both break the hard link to the 'B' key so I can have air brakes operate separate from landing gear. Additionally, I'd like to be able to use them like the BAC9 surface air brakes where they can be incrementally adjusted using action groups.

Overall, this is the best mod for KSP.

[somnambulist]

Surprised no one has ever brought this up, but the all new spaceplane friendly SAS still doesn't work with FAR. At all. It either randomly oscillates up and down or just does nothing. And the FAR yaw damper, wing leveler etc. have never worked for me.

FAR newbie here but I was going to write something up about this. The stock Aeris 3A enters into a 1-2 Hz pitch oscillation if you turn the sas on below about 5km. Trimmed properly it flys very well with the sas off and is smooth with sas on from 5km+. The only thing I can think of is that the sas is expecting instaneous control surface response, overreacts and starts a feedback loop.

[Frederf]

A small feature request. Is it possible to code in a simple ARI helper that can be turned on/off like the pitch damper and yaw damper?

[Van Disaster]

BTW anyone notice how cargo bays and FAR simply don't mix? If the root of any wing that I attach to a cargo bay is touching said cargo bay, the then wing is considered to be shielded. This causes a large reduction in drag, and causes inaccurate aerodynamics IIRC. Can anyone shed some light on a possible solution?

This was fixed a *long* time ago - either it's slipped back in again or you're running several versions behind.

[longhornchris]

FAR newbie here but I was going to write something up about this. The stock Aeris 3A enters into a 1-2 Hz pitch oscillation if you turn the sas on below about 5km. Trimmed properly it flys very well with the sas off and is smooth with sas on from 5km+. The only thing I can think of is that the sas is expecting instaneous control surface response, overreacts and starts a feedback loop.

Well, while the new SAS is much better behaved, I still think they are running a PID based control with a few extras thrown in. My guess is that C7 added filtering either on the feedback input or the PID output, and adjusted the scaling to account for both control authority / inertia ratios. The filtering would prevent/limit the oscillations as the controller won't drive high frequency, while the scaling would ensure control doesn't go bang-bang unless you have little control to start with.

That said, FAR adds in a few significant complications. First, control authority in FAR is heavily dependent on flight conditions and varies with altitude and airspeed (dynamic pressure really). My guess is that while the SAS gains 'adjust' in real time with the vehicle inertias, I doubt the scaling accounts for any FAR adjusting items.

Second, and perhaps more troubling, is that aircraft have significantly more complicated and variable cross-axis coupling - with roll-yaw coupling being the simplest. The cross axis coupling is both design and flight condition dependent, and real aircraft designers have to take this into account when setting up control aids and/or autopilots.

With the extra variables, its likely that the 'properly damped' SAS for rockets is under damped for many FAR planes, at least under certain flight conditions.

The only solution I've found so far is to have a stable and properly trimmed plane until I get high/fast enough for SAS to be stable... and that varies with each airplane.

[Leicontis]

Is there a Version History for this mod anywhere? I haven't found one, and having to sort through page after page of forum for Ferram's posts is a bit tiresome...

[ferram4]

@White Owl & Weatherman159: I guess I'll just scrap the fixes to the blunt body aerodynamics since they "feel" wrong. I guess I can't seem to get them right. In the meantime, make sure that all of your wings are actually "FAR-ized" by right-clicking on each one and making sure that Cl, Cd and Cm values show up; ModuleManager might be screwing up.

@rpayne88: That looks like it's a bug caused by either the B9 aerospace wings not properly using the FAR aerodynamics or the stock canard aerodynamics not being properly overwritten. Make sure that you're using the most up-to-date version of ModuleManager and that there aren't multiple copies of that dll in your GameData folder.

@SkyHook: The Cargo-Bays-shielding-parts-they-shouldn't-be was supposed to have been solved; make sure you're running the most recent version and then post a picture along with a craft and a link to the mods necessary to build it.

@SpaceRodent: FAR uses ModuleManager, so it doesn't actually change anything in any of the Parts folders anymore.

@Obj4ct7: SAS doesn't expect the minor control delay that FAR introduces and your stages probably aren't struted up enough to counteract the wibbly-wobbly joints bug. Use fixed winglets or fly without SAS; you shouldn't need SAS for ascents with FAR.

@DividedByZero: The new SAS was fine with FAR until everyone complained that it wasn't as quick to respond to errors in orientation... and then C7 made it more twitchy. But see the above answer for why that would happen; try using the dampers but reduce the "k" value to something smaller.

@longhornchris: The raise and lower commands are for flaps, not airbrakes currently.

[NathanKell]

ferram, any thoughts on the parachutes? I'm not sure what else I can try to eliminate the extra drag...

Also, while I'm asking: Any chance of your revisiting your position on the area rule?

[Istagg]

Everything he said, I want to say too. The planes handle slightly better than before, but they still seem to have way too little drag. Every plane I try to land is extremely floaty and just won't slow down. The L/D line is still a near vertical line right off the top of the graph.

The problem first appeared for me in 0.9.5.2. I'm still using 0.9.5.1 in KSP .20.2 for now.

I have to add my voice to Weatherman159 and White Owl here. FAR works great, except for one key issue. There seems to be no drag to speak of.

I can take off and climb to a speed of lets say 200 m/s, and the planes handle great.

But when i shut the engines down, i can glide around for minutes almost. It just wont slow down. Is there no fix for this issue?

I spend most of my time designing and flying planes in KSP, and i love this mod. It has become indispensable to me.

[White Owl]

@White Owl & Weatherman159: I guess I'll just scrap the fixes to the blunt body aerodynamics since they "feel" wrong. I guess I can't seem to get them right. In the meantime, make sure that all of your wings are actually "FAR-ized" by right-clicking on each one and making sure that Cl, Cd and Cm values show up; ModuleManager might be screwing up.

Ferram, I'm very sorry to cause you irritation like this. Your work here is the single greatest mod to this game, and the only mod I consider indispensable; I would happily uninstall everything else if it meant I could keep FAR. If it's worth anything, I personally know exactly what it's like to put a lot of work into something, only to see a bunch of comments from semi-anonymous internet strangers saying it could be better if I'd only do _____.

If you say the prior versions of FAR had way too much drag, and the new version is how it's supposed to work, then I'll be quiet and deal with the enormous change.

I took the FAR Firebolt for a spin, and right-clicked on the wing parts in flight. Cl and Cd values updated with changes to AoA and airspeed, and Cm remained 0 at all times.

[SkyHook]

Ferram, I'm very sorry to cause you irritation like this. Your work here is the single greatest mod to this game, and the only mod I consider indispensable; I would happily uninstall everything else if it meant I could keep FAR. If it's worth anything, I personally know exactly what it's like to put a lot of work into something, only to see a bunch of comments from semi-anonymous internet strangers saying it could be better if I'd only do _____.

If you say the prior versions of FAR had way too much drag, and the new version is how it's supposed to work, then I'll be quiet and deal with the enormous change.

I took the FAR Firebolt for a spin, and right-clicked on the wing parts in flight. Cl and Cd values updated with changes to AoA and airspeed, and Cm remained 0 at all times.

I second your sentiments, Owl. Every time I see a new craft with no engines and 200 small control surfaces break the sound barrier, I cry, and thank baby Jesus that I have FAR!

[NathanKell]

Ditto. FAR is utterly experience-changing, and I can't give kudos enough. Needs to be repeated at least once a page.

[Dirt_Merchant]

I feel like it needs to be said several times per page;) FAR makes ksp for me.

[ferram4]

@Leicontis: Sorry I didn't get to you last post, a version history is listed at the bottom of the README file included in the download. I removed the copy that was in the first post when the forum's spoiler function was removed.

@NathanKell: I honestly don't know what else to do to remove the extra drag. Perhaps it isn't the parachute and is simply the MechJeb part that is contributing to the drag increase?

@Everyone with positive comments about FAR: Thanks, though the extent of support for FAR makes me wonder if this is how cults start. Most of my frustration is caused by the fact that I've been rushing through hotfixes somewhat hectically with the recent KSP updates and then I find out there are more bugs. Don't sweat it guys, keep the complaints coming; they make the mod better.

So version 0.9.5.5 is out. The L/D scaling bug has been fixed and the majority of the blunt body drag code has been reset; the only part remaining is the change to drag for a part in crossflow. I suspect some of the drag complaints might simply be driven by the erroneous L/D graph (basically, I screwed up and the 1/10 scaling was removed). I also removed my copy of the FAR.cfg that was causing the Flight GUI to appear offscreen for some people with lower screen resolutions.

[SkyHook]

Sorry Ferram, the CoL is gone with this latest update of FAR. Tests without FAR lead to the indicator returning. Also, a quick suggestion, would it be possible to add a Center of Drag indicator to the game? I think that it would be helpful.

[ferram4]

Should be fixed now. I included the wrong version of FerramAerospaceResearch.dll.

[NathanKell]

@ferram, alas no. Parachutes are the only thing that add drag to the drag calculator. (I don't even use a part for MJ; it's MM'd onto the probes and pods). It's really only a bad problem with very aerodynamic rockets (where I expect total deltaV expenditure for 75x75 orbit on the order of 3100m/s); on less aerodynamic ones it's a much smaller portion of the total. But it's _weird_ that zeroing drag still leaves me with 50m/s of it!

I do recommend, however, that you maybe consider zeroing stowedDrag for parachutes in your MM config? Otherwise they will quite massively increase drag, especially for itty-bitty rockets where they make up a large proportion of the mass (do the to mass-weighted drag equation Squad uses).

...unless people just don't bother to make aerodynamic rockets?