[1.8-1.12] Ferram Aerospace Research Continued: v0.16.0.5 "Mader" 03/04/22

[Krazy1]

On 6/13/2022 at 7:17 PM, jwbrase said:

So I'd say your L/D is reasonable.

Thanks for the comments. Yeah, it's showing about 14:1 subsonic in the editor (with neutral elevator which isn't really accurate so I should try different angles). Gear down it's virtually identical. I just think the gear don't have enough drag. It also has delta wings so the aspect ratio is much lower than typical passenger planes. The Shuttle L/D was 4.5:1 but it was tailless.

Spoiler

At hypersonic velocities in the upper atmosphere, above about Mach 5 and 200,000 feet, the Shuttle glides at a 1:1 ratio, one foot of forward travel for each foot of descent, about the same as a Steinway. That increases to 2:1 at supersonic velocities and improves to about 4.5:1 when you're on final approach

On 6/13/2022 at 7:17 PM, jwbrase said:

the mountains to the west of the KSC enforce a fairly aggressive descent rate

I tend to overshoot east and fly back over the ocean to avoid the mountains. I did one approach over the mountains and dove down the east slope subsonic with the gear down and still sailed past the runway.

On 6/13/2022 at 7:17 PM, jwbrase said:

What I have found is that FAR planes tend to have both less lift and less drag than stock, so takeoff / landing speeds are often ~50% higher

Yeah. S-turns are difficult too because like you said lift is low so I can't maneuver aggressively. I'll just need to add flaps/ spoilers/ chutes.

Edit: some discussion here saying the drag in a passenger jet is roughly doubled with gear down. 

https://aviation.stackexchange.com/questions/32469/how-much-extra-drag-does-landing-gear-incur

Edited June 19, 2022 by Krazy1

[jwbrase]

10 hours ago, Krazy1 said:

Thanks for the comments. Yeah, it's showing about 14:1 subsonic in the editor (with neutral elevator which isn't really accurate so I should try different angles). Gear down it's virtually identical. I just think the gear don't have enough drag. It also has delta wings so the aspect ratio is much lower than typical passenger planes. The Shuttle L/D was 4.5:1 but it was tailless.

 

The shuttle was a really aggressively swept delta.

 

10 hours ago, Krazy1 said:

Yeah. S-turns are difficult too because like you said lift is low so I can't maneuver aggressively. I'll just need to add flaps/ spoilers/ chutes.

 

Lift is low in FAR compared to stock, but planes in general lose tons of energy in a stall and deltas absolutely bleed energy before they get near the stall (the wingtip vortices from the front part of the wing inject energy on the upper surface of the back part of the wing, delaying the stall to higher angles of attack). If you've got a delta-ish planform and you're having trouble maneuvering aggressively enough to get down to your straight-and-level stall speed well short of the runway, you likely have a balance or control-authority issue and probably aren't getting anywhere near stalling with full stick back: this will negatively impact the flyability of your spaceplane in all flight regimes except vacuum: reentry will be hotter for a given aggressiveness of deceleration, transitioning from a jet-powered lifting ascent to a rocket-powered ballistic ascent will be more difficult, and subsonic flight will have the character you describe. In extreme cases there may be parts of the flight envelope in the mach 1 to mach 2 region where you have no up-elevator authority at all.

If you *are* managing to pull enough AOA to get near the stall, and your stall speed is super high, you probably just don't have enough wing area.

Can you post an overhead view of your spaceplane with CoM and CoL showing, and screenshot of a FAR AOA sweep at 0.5 Mach and at 0, 0.5, and 1 pitch settings?

 

10 hours ago, Krazy1 said:

Edit: some discussion here saying the drag in a passenger jet is roughly doubled with gear down. 

https://aviation.stackexchange.com/questions/32469/how-much-extra-drag-does-landing-gear-incur

Gear could probably afford to be more draggy in FAR, but you shouldn't really need it to be draggy.

[Artyloo]

Hello there,

Is there anything in the FAR model that could cause this weird sideways drag on a symmetrical, level aircraft?

https://imgur.com/a/P29ZeeS

The drag sometimes oscillates from left to right.

Or is it definitely an issue with another mod?

 

Edited June 28, 2022 by Artyloo

[NippyFlippers]

Is there a way to increase lift and drag at low speeds a little bit?

Actually, I think it needs to be increased by quite a lot.

Even biplanes need to reach blistering speeds (70m/s) to get airborne, when they could take off at a pedestrian 40m/s beforehand and most scaringly they simply refuse to slow down when in descending flight, no matter how swallow the angle of approach.

My prop planes barely can get off the ground and landings have become nigh impossible, now.

Edited June 30, 2022 by NippyFlippers

[Slam_Jones]

Hello!  Quick question here.

Do wing fences help redirect airflow over a swept wing, such as with the Mig-17?  Doing some Top Gun stuff and trying to get the best performance possible over a wide range of aircraft and wing styles.

Thanks!

[msp307]

 

Hi I'm trying to get my space shuttle to fly from SOCK in RSS/RO with FAR can anyone help me?

[Jacke]

8 hours ago, Slam_Jones said:

Do wing fences help redirect airflow over a swept wing, such as with the Mig-17?  Doing some Top Gun stuff and trying to get the best performance possible over a wide range of aircraft and wing styles.

https://en.wikipedia.org/wiki/Wing_fence

Quote

Wing fences, also known as boundary layer fences and potential fences are fixed aerodynamic devices attached to aircraft wings. Often seen on swept-wing aircraft, wing fences are flat plates fixed to the upper surfaces parallel to the wing chord and in line with the free stream airflow, typically wrapping around the leading edge. By obstructing span-wise airflow along the wing, they prevent the entire wing from stalling at once, as opposed to wingtip devices, which increase aerodynamic efficiency by seeking to recover wing vortex energy.

 

[Slam_Jones]

Thank you for the info!  I actually found that page during my research.  It is what lead me to my question.

I guess I should be more specific: I understand that wing fences work in real life, but do they work in FAR?  Is the airflow simulation accurate enough for wing fences to affect performance of swept-wing aircraft?

[Beetlecat]

On 6/30/2022 at 2:29 AM, NippyFlippers said:

Is there a way to increase lift and drag at low speeds a little bit?

Actually, I think it needs to be increased by quite a lot.

Even biplanes need to reach blistering speeds (70m/s) to get airborne, when they could take off at a pedestrian 40m/s beforehand and most scaringly they simply refuse to slow down when in descending flight, no matter how swallow the angle of approach.

My prop planes barely can get off the ground and landings have become nigh impossible, now.

I know this was asked weeks ago, but the question is still relevant.

This was / is my learning curve with FAR as well. It's a great re-work of the KSP atmospheres, but still doesn't quite operate like "we think it should" probably due to the weird scale/mass of things in KSP.

Aircraft tend to (once airborne) slip through the air quickly, but do not lose speed due to drag as readily as we expect from usual plane shapes.  Obviously, just throwing on a bunch of flaps, spoilers, and brakes can be a solution -- but by also making sure aircraft are as light as possible;  FAR provides a way of easily doing this with wings-- make sure you dial the strength/mass down as far as you can on every wing and control surface. Testing flights will reveal if you've gone too far.   I've also had good results from making wings a *bit* bigger than expected.

Your example of the biplane makes sense considering the plane's construction. If the wings and body are made of plywood, you're going to need a *lot* more thrust to get airborne vs canvas and frames.

There's also lots of tweaking of wing shape and angle that can be done to achieve some dramatic improvements to control and performance--including being able to slow down!   Changing position and attitude of landing gear can help with take-off & landing as well.

The in-editor analysis panels are mostly above my ken, but just make sure everything is in the green at your desired airspeeds and you should be okay.
 

Edited July 25, 2022 by Beetlecat

[Krazy1]

Help... having a constant problem with parachutes. When reentering, they always deploy while going too fast and instantly get destroyed. I'm arming them in space like normal and they just deploy too soon. I'm using Mk16-XL and Mk25. They have default settings including "deploy when safe" but they are not doing so. I just tried to land on Laythe and the drogues deployed at about 1200 m/s at 22 km up. The mains deployed at over 1100 m/s. 

[DA299]

Hello, I just wanted to ask, that whether it'd be possible to make FAR model compression lift at hypersonic regimes? High speed aircraft(like Valkyrie of Blackbird) have really high L/D IRL compared to in FAR, and IMO it would make reaching orbit a lot easier with FAR(especially in scaled systems or RSS). Right now, FAR spaceplanes have very comparable performance to those using stock aero; and IMO it would be a huge addition to gameplay if this is implemented. Doesn't need to be 100% accurate, but some increase in lift using wing sweep and anhedral angle as variables, would be much appreciated.

[DA299]

On 7/25/2022 at 12:01 AM, Beetlecat said:

I know this was asked weeks ago, but the question is still relevant.

This was / is my learning curve with FAR as well. It's a great re-work of the KSP atmospheres, but still doesn't quite operate like "we think it should" probably due to the weird scale/mass of things in KSP.

Aircraft tend to (once airborne) slip through the air quickly, but do not lose speed due to drag as readily as we expect from usual plane shapes.  Obviously, just throwing on a bunch of flaps, spoilers, and brakes can be a solution -- but by also making sure aircraft are as light as possible;  FAR provides a way of easily doing this with wings-- make sure you dial the strength/mass down as far as you can on every wing and control surface. Testing flights will reveal if you've gone too far.   I've also had good results from making wings a *bit* bigger than expected.

Your example of the biplane makes sense considering the plane's construction. If the wings and body are made of plywood, you're going to need a *lot* more thrust to get airborne vs canvas and frames.

There's also lots of tweaking of wing shape and angle that can be done to achieve some dramatic improvements to control and performance--including being able to slow down!   Changing position and attitude of landing gear can help with take-off & landing as well.

The in-editor analysis panels are mostly above my ken, but just make sure everything is in the green at your desired airspeeds and you should be okay.
 

Its much better to just use something like SMURFF or RealFuels to alter part masses so that they more closely mimic those IRL. But even with those two enabled, and with realistic part densities, landing planes in FAR is harder than IRL(The stall speeds are higher). Two main reasons for this, which IMO have a bigger effect combined than part mass:

1) FAR only models angle-of-incidence lift, and thus, wings which are completely flat. It does not even consider curved airfoil cross-sections, and those have much, much better L/D ratios at low speeds (<100 m/s). They also have critical AoAs far higher than flat plates, so there's that.

2) FAR doesn't model ground effect, which is a huge help when  landing. 

Despite these limitations, I truly think that for speeds between Mach 0.5 to Mach 2; FAR is very, very close to real life. 

On 6/30/2022 at 2:29 PM, NippyFlippers said:

Is there a way to increase lift and drag at low speeds a little bit?

Actually, I think it needs to be increased by quite a lot.

Even biplanes need to reach blistering speeds (70m/s) to get airborne, when they could take off at a pedestrian 40m/s beforehand and most scaringly they simply refuse to slow down when in descending flight, no matter how swallow the angle of approach.

My prop planes barely can get off the ground and landings have become nigh impossible, now.

Post some pics of your design here. I can make a Flanker replica take off at less than 60 m/s ; so there's likely sth wrong with your design(Perhaps too little control authority?)

[NippyFlippers]

6 hours ago, DA299 said:

Its much better to just use something like SMURFF or RealFuels to alter part masses so that they more closely mimic those IRL. But even with those two enabled, and with realistic part densities, landing planes in FAR is harder than IRL(The stall speeds are higher). Two main reasons for this, which IMO have a bigger effect combined than part mass:

1) FAR only models angle-of-incidence lift, and thus, wings which are completely flat. It does not even consider curved airfoil cross-sections, and those have much, much better L/D ratios at low speeds (<100 m/s). They also have critical AoAs far higher than flat plates, so there's that.

2) FAR doesn't model ground effect, which is a huge help when  landing. 

Despite these limitations, I truly think that for speeds between Mach 0.5 to Mach 2; FAR is very, very close to real life. 

Post some pics of your design here. I can make a Flanker replica take off at less than 60 m/s ; so there's likely sth wrong with your design(Perhaps too little control authority?)

Sure, here are some of my creations:

And a folding wing design so it can be transported as cargo.

It weighs about 5t and needs 80m/s to take off. Maybe it is the B9-procedureal wing that is the issue?

 

[DA299]

4 hours ago, NippyFlippers said:

Sure, here are some of my creations:

And a folding wing design so it can be transported as cargo.

It weighs about 5t and needs 80m/s to take off. Maybe it is the B9-procedureal wing that is the issue?

 

I can't say for sure what's wrong with the biplane, but for the folding wing craft, you most likely do not have enough pitch authority. Those Elevators aren't doing you any favors, either use bigger ones, or move them further from the COM (a lot further). First try using the all-moving control surface from B9 wings, and set it to control only pitch. Other things to make sure of are that the back landing gear aren't too far from the COM( but I suspect you already know that.)

What does the FAR window say about this craft? Tell you what, if you screenshot the numbers it gives you in the SPH, I'll be able to help you out immensely. Here's what you gotta do: Select the 'data+stability derivatives' window, set speed to Mach 0.18, and click run analysis. Then screenshot that.

_________________________________________________________________________________________________________________________________________________________________________

 

Here's one of my crafts, that also weighs about 5 tons, and can take-off and land perfectly well under 50 m/s. In fact, with half fuel, it can probably take-off <40 m/s. Its dimensions and wing area are probably similar to your second plane, that's why I think there's a problem with nose authority.

Edited August 15, 2022 by DA299

[NippyFlippers]

49 minutes ago, DA299 said:

I can't say for sure what's wrong with the biplane, but for the folding wing craft, you most likely do not have enough pitch authority. Those Elevators aren't doing you any favors, either use bigger ones, or move them further from the COM (a lot further). First try using the all-moving control surface from B9 wings, and set it to control only pitch. Other things to make sure of are that the back landing gear aren't too far from the COM( but I suspect you already know that.)

What does the FAR window say about this craft? Tell you what, if you screenshot the numbers it gives you in the SPH, I'll be able to help you out immensely. Here's what you gotta do: Select the 'data+stability derivatives' window, set speed to Mach 0.18, and click run analysis. Then screenshot that.

_________________________________________________________________________________________________________________________________________________________________________

 

Here's one of my crafts, that also weighs about 5 tons, and can take-off and land perfectly well under 50 m/s. In fact, with half fuel, it can probably take-off <40 m/s. Its dimensions and wing area are probably similar to your second plane, that's why I think there's a problem with nose authority.

Those are allmoving tailplanes and pitch authority is A-okay. I think I can even dial back the wing incidence angle by quite a bit, but despite all that wing area it still needs a scary ammount of groundspeed to take off.

Here, do you mean this?

Edited August 15, 2022 by NippyFlippers
added picture

[610yesnolovely]

On 5/9/2021 at 4:03 PM, stk2008 said:

Thanks for update.

Just to say this is still an issue

not sure if you remember me last post but in cockpit view as soon as generating data for (any Ast) FPS drops the below 30 and even lower after more messages like that.

I can regain FPS by just going into external view or map view then its all fine again in cockpit view till that message shows again.

This never happens if I just stay in external view.

 

I had exactly the same issue occuring, and as described, with FAR installed (and perhaps requiring Kopernicus) any asteroid spawning while in IVA causes the FPS to drop to single digits. As the OP said, if you quickly switch out of IVA, the problem immediately clears, but will return when the next asteroid spawns while in IVA. Does not happen if in any other view.

The logs only show what the OP says, it only happens as soon as Kopernicus spawns an asteroid. I also tried an MM patch on Kopernicus_config to set Kopernicus' UseKopernicusAsteroidSystem=Stock - same thing happens when stock spawns a comet or asteroid. The work around is to quickly switch out and back, but asteroid spawning happens frequently enough that this is a bit annoying.

It might be that voxelization of any new vessel, even unloaded, (as it seems asteroids/comets get a FARAeroVessel and are considered vessels) while in IVA causes some issue - I wonder if the IVA view uses something that conflicts with FAR? Shaders? Threads? I have no idea. It might be that having an option to ignore asteroids/comets for voxelization would be a "hack" fix.

Not expecting a solution, this is more "FYI" just in case anyone else gets stuck on this, or if any FAR mod authors have a moment of inspiration given this info.

Edited August 17, 2022 by 610yesnolovely

[Beetlecat]

Would either of you  be willing to share .craft files? I really like the looks of your craft, and love looking at other people's designs close-up. It makes for great inspiration (+ help with troubleshooting)!

On 8/15/2022 at 11:55 AM, DA299 said:

Here's one of my crafts, that also weighs about 5 tons, and can take-off and land perfectly well under 50 m/s. In fact, with half fuel, it can probably take-off <40 m/s. Its dimensions and wing area are probably similar to your second plane, that's why I think there's a problem with nose authority.

On 8/15/2022 at 7:46 AM, NippyFlippers said:

 

 

[DA299]

9 hours ago, Beetlecat said:

Would either of you  be willing to share .craft files? I really like the looks of your craft, and love looking at other people's designs close-up. It makes for great inspiration (+ help with troubleshooting)!

 

Sure, here ya go:

https://drive.google.com/drive/folders/1QshEwLKVBysWqJQwKzdTsRc1qC7nYf7v?usp=sharing

I play with a lot of mods though. These particular craft were built with the following:

1) FAR

2) RealFuels-Stock

3) b9 procedural wings

4) procedural parts

5) Firespitter

6) Airplane Plus

7) SMURFF (for adjusting pod weight.)

7) Atmosphere Autopilot (Its not mandatory but highly recommended.)

[NippyFlippers]

On 8/19/2022 at 2:11 AM, Beetlecat said:

Would either of you  be willing to share .craft files? I really like the looks of your craft, and love looking at other people's designs close-up. It makes for great inspiration (+ help with troubleshooting)!

 

Yes, sure.

The modpack: https://www.dropbox.com/s/li2wz353s73zkvt/modpack.ckan?dl=0

The biplane: https://www.dropbox.com/s/vzlntwtdlpfi4ml/Double Trouble Taildragger.craft?dl=0

The folding wing twinjet: https://www.dropbox.com/s/td96qy87px1o5x4/Open Twinjet Folding Wing.craft?dl=0

I hope these links work, first time using that filehost.

Edit: The main gear on the floding wing neesd to steer a bit more to the outsides, so it is more stable on landing. A degree or two off the centerline should be enough.

Edited August 20, 2022 by NippyFlippers

[tychochallenge]

On 8/17/2022 at 1:15 PM, 610yesnolovely said:

I had exactly the same issue occuring, and as described, with FAR installed (and perhaps requiring Kopernicus) any asteroid spawning while in IVA causes the FPS to drop to single digits. As the OP said, if you quickly switch out of IVA, the problem immediately clears, but will return when the next asteroid spawns while in IVA. Does not happen if in any other view.

The logs only show what the OP says, it only happens as soon as Kopernicus spawns an asteroid. I also tried an MM patch on Kopernicus_config to set Kopernicus' UseKopernicusAsteroidSystem=Stock - same thing happens when stock spawns a comet or asteroid. The work around is to quickly switch out and back, but asteroid spawning happens frequently enough that this is a bit annoying.

It might be that voxelization of any new vessel, even unloaded, (as it seems asteroids/comets get a FARAeroVessel and are considered vessels) while in IVA causes some issue - I wonder if the IVA view uses something that conflicts with FAR? Shaders? Threads? I have no idea. It might be that having an option to ignore asteroids/comets for voxelization would be a "hack" fix.

Not expecting a solution, this is more "FYI" just in case anyone else gets stuck on this, or if any FAR mod authors have a moment of inspiration given this info.

I have this exact same issue, I just narrowed the problem down to this mod after hours of testing 

[Beetlecat]

On 8/19/2022 at 2:37 AM, DA299 said:

Sure, here ya go:

https://drive.google.com/drive/folders/1QshEwLKVBysWqJQwKzdTsRc1qC7nYf7v?usp=sharing

I play with a lot of mods though. These particular craft were built with the following:

1) FAR

2) RealFuels-Stock

3) b9 procedural wings

4) procedural parts

5) Firespitter

6) Airplane Plus

7) SMURFF (for adjusting pod weight.)

7) Atmosphere Autopilot (Its not mandatory but highly recommended.)

Nice --  Yeah -- I'm almost always "chock full o' mods", so there's likely no issue loading it for me except for maybe SMURFF.

[NippyFlippers]

I am sorry, but I have to restrain from using this mod.

As it is now it simply does not like robotic parts used in swing- or folding wing designs and prevents mods like Atmosphere Autopilot or even the stock SAS from functioning.

Edited August 24, 2022 by NippyFlippers

[siimav]

50 minutes ago, NippyFlippers said:

and prevents mods like Atmosphere Autopilot [snip] from functioning

No idea about the other complaints but that part definitely isn't true.

[NippyFlippers]

On 8/24/2022 at 9:48 PM, siimav said:

No idea about the other complaints but that part definitely isn't true.

In conjunction with robotic parts. Static wings work just fine. But the mod causes SAS/Atmosphere Autopilot to seize on anything with wings that use hinges, servos or motors to swing, fold or flap.

As soon as I revert from this mod back to stock aerodynamics, everyting works as intended.

It pains me, but I simply can't use this one.

Edit: I was wrong. The bug is back, randomly preventing the SAS system from engaging correctly. So this mod can obviously be ruled out as the cause. I am at a loss.

Edit2: I tracked that bug down to the moderation option in the mod "AtmospheAutopilot". Disableing the moderataion in the craft settings fixes the problem.

 

Edited August 30, 2022 by NippyFlippers

[infinite_monkey]

Is anyone else getting this logspam?

Spoiler

[EXC 20:11:14.991] NullReferenceException: Object reference not set to an instance of an object
    FerramAerospaceResearch.FARPartGeometry.BoundsRenderer.OnPostRender () (at <112e95c6a78b45029cd70a531e9d5c39>:0)
    UnityEngine.DebugLogHandler:LogException(Exception, Object)
    ModuleManager.UnityLogHandle.InterceptLogHandler:LogException(Exception, Object)
    UnityEngine.Debug:CallOverridenDebugHandler(Exception, Object)
[ERR 20:11:14.993] Matrix stack full depth reached

[ERR 20:11:14.993] Matrix stack full depth reached

[ERR 20:11:14.993] Matrix stack full depth reached

[EXC 20:11:15.008] NullReferenceException: Object reference not set to an instance of an object
    FerramAerospaceResearch.FARPartGeometry.BoundsRenderer.OnPostRender () (at <112e95c6a78b45029cd70a531e9d5c39>:0)
    UnityEngine.DebugLogHandler:LogException(Exception, Object)
    ModuleManager.UnityLogHandle.InterceptLogHandler:LogException(Exception, Object)
    UnityEngine.Debug:CallOverridenDebugHandler(Exception, Object)
[ERR 20:11:15.010] Matrix stack full depth reached

[ERR 20:11:15.010] Matrix stack full depth reached

[ERR 20:11:15.010] Matrix stack full depth reached
...

And I get this in EVERY situation - administration building, paused game... Why is FAR even doing anything in these situations?