ferram4

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

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I downloaded KSP-AVC and it told me the only compatibly issue was ModularFlightIntegrator so I downloaded the 1.2.0 version, still no joy.

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@RazorFang95: Based on what you've said, the only thing I can think of is that your computer is not allowing FAR's background voxelization process to run.  I don't know what kind of locked-down settings you have on your machine, or what your machine is also doing that doesn't allow it to give up a few cores to run those processes, but that's what it sounds like is happening.  Nothing I can fix, it's your settings that need to change.

@bckspstuff: 1) You don't do anything for lifting bodies of any kind.  Nothing, nada.  The only reason the modules are still on the pods is that no one told me they were added, and so I didn't remove them.  FAR doesn't remove those modules universally on the principle of, "well, even if the stock modules are completely and horribly wrong, if FAR isn't replacing them with wing modules it's safer to leave them there.  It's not like they'll be misused to hack things together that shouldn't be hacked together, right?"  So, me being naive and expecting things done right.

2) Stock engines have pitifully small gimbal ranges, well below real life.  This means that rockets have very little gimbal control authority in KSP by default, far less than is necessary to fight the standard aerodynamic instability of most rocket designs.  The speed setting is to make the gimbals move smoothly rather than jerking, which can cause the shakes and make rockets come apart very quickly.

3) So long as the part isn't a blade and is at least somewhat part of the aerodynamic fairing of the propeller, it's okay.  It's the propeller blades and the transparent blur-disk itself that can't be voxelized.

@Vladokapuh: Whatever works, but I'm not sure exactly how you're slowing down something that's going at least half the speed of sound on the runway.  Frankly, it sounds like your plane is just too damn heavy if you need all that speed to land it safely.  If I had to guess, going slower causes it to fall out of the sky and bellyflop into the ground due to a lack of lift, but going as fast as you are gives it too much lift, so you need to slam it down to give it a chance to not immediately take off again.  I'd say, make it lighter / more wing and add more pitch authority; come in slower, with a higher AoA.  Then, you shouldn't risk bouncing back into the air so much and you won't need to land so fast.

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I have no idea, this is something that shouldn't occur unless you've changed some settings to make it happen.  If I had to make a wild-ass guess, it would be your antivirus being some kind of crazy-obsessive thing, but if that's not it, I dunno what to tell you.

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1 hour ago, ferram4 said:

I have no idea, this is something that shouldn't occur unless you've changed some settings to make it happen.  If I had to make a wild-ass guess, it would be your antivirus being some kind of crazy-obsessive thing, but if that's not it, I dunno what to tell you.

No joy yet on the antivirus. Could it be because my cpu came out of a crackerjack box?

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@ferram4Thanks so much for your help. I think that clarifies everything I need to know.

Yeah, I hear ya' on odd things in stock modules. I get both sides; sometimes devs need to do what they need to do to get it out the door, but from the community side it would be helpful if the code were more rigorous. Seeing under the hood of a favorite game when modding is sometimes a little like seeing your best friend in sweat pants: no one looks good in sweat pants, but you just have to remember how much you love them or you wouldn't have been hanging out in sweat pants in the first place. :)

BTW, you've done a great job. So far I've checked the voxels on every part for well over 100 mods and by-and-large FAR has handled everything with flying colors. Nice job!

Edited by bckspstuff
link

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15 hours ago, ferram4 said:

@Vladokapuh: Whatever works, but I'm not sure exactly how you're slowing down something that's going at least half the speed of sound on the runway.  Frankly, it sounds like your plane is just too damn heavy if you need all that speed to land it safely.  If I had to guess, going slower causes it to fall out of the sky and bellyflop into the ground due to a lack of lift, but going as fast as you are gives it too much lift, so you need to slam it down to give it a chance to not immediately take off again.  I'd say, make it lighter / more wing and add more pitch authority; come in slower, with a higher AoA.  Then, you shouldn't risk bouncing back into the air so much and you won't need to land so fast.

Actually no, ive been making relatively light planes with big wings and well balanced, that can also handle high AoA. I've been landing them really really lightly, with very very tiny vertical speed. (im usually landing at below 1m/s vertical, and gear still bounces)
The problem i encounter is that on contact, the suspension moves a bit, and then for some reason resets, and even in a really nice landing it just catapults the plane up. Landing fast i actually force the wings and all the lift to keep me stable on the ground. 
Also when doing my high speed landing i land next to runway, slow down and then ride back to KSC.
My card is dying but i could try to record what i mean. edit: nope, no way, lol

Edited by Vladokapuh

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You might try KSPWheel based landing gear, rather than stock. Perhaps the problem is not FAR-related.

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49 minutes ago, damerell said:

You might try KSPWheel based landing gear, rather than stock. Perhaps the problem is not FAR-related.

i arleady mention its not a FAR issue, FAR just makes it more apparent.
Again, i have a workaround anyways so, no major problems here. Enjoying the mod :)

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I'm about to try playing the ksp_update branch with 128 other mods. I will have no useful bug reports. I might complain anyways. Wish me luck.

Spoiler

KSP: 1.3 (Win64) - Unity: 5.4.0p4 - OS: Windows 10  (10.0.0) 64bit
000_AT_Utils - 1.4.4
Toolbar - 1.7.14
USI Tools - 0.9.2
Ablative-Airbrake - 0.2
AutomatedScreenshots - 0.8.0.1
B9 Part Switch - 1.8.1
Chatterer Extended - 0.6.1
Chatterer - 0.9.93.1804
CIT_Util - 1.4
BAM - 1.3
CollisionFX - 4.0
Community Category Kit - 2.0.1
Community Resource Pack - 0.7
CommunityTechTree - 3.1.1
ConfigurableContainers - 2.4.1
Connected Living Space - 1.2.5.3
Crowd Sourced Science - 4.1
DangerAlerts - 1.4
DistantObjectEnhancement - 1.9
DMagic Orbital Science - 1.3.0.10
CapCom Mission Control On The Go - 1.0.2.6
Contract Parser - 1.0.6
Contracts Window Plus - 1.0.8
Progress Parser - 1.0.7
Easy Vessel Switch - 1.3
EVAFuelContinued - 1.5
EVA Struts - 1.0.4
EVA Transfer - 1.0.7
Ferram Aerospace Research - 0.15.8.1
Firespitter - 7.6
Flexible Docking - 1.0.5
FMRS (Flight Manager For Reusable Stages) - 1.2.5
GroundConstruction - 1.2
Hangar - 3.3.2
Interstellar Fuel Switch - 2.6.3
JanitorsCloset - 0.3.2
Kerbal Attachment System - 0.6.3
Kerbin Environmental Institute - 1.2.2.130
Kerbal Foundries - 2.0.2.6
Stork - 0.2.6
Kerbal Inventory System - 1.5
<b><color=#CA7B3C>Kopernicus</color></b> - 1.3.0.4
KSP-AVC Plugin - 1.1.6.2
KSPWheel - 0.9.5.16
KWRocketryRedux - 3.1.4
Infernal Robots - 2.0.11
Mk1-Cabin-Hatch - 0.2
Modular Rocket Systems - 1.13.1
ModularFlightIntegrator - 1.2.4
Monthly Budgets - 2.7
NearFutureConstruction - 0.8.2
NearFutureElectrical - 0.9.1
NearFuturePropulsion - 0.9.1
NearFutureSolar - 0.8.3
Portrait Stats - 1.0.14
Mk2.5 Spaceplane Parts - 1.4.1
RCS Sounds - 5.2
RealChute - 1.4.4
RealPlume - Stock - 0.11.4
Recovery Controller - 0.0.2
ReentryParticleEffect - 1.2.0.1
RemoteTech - 1.8.7
AmpYear - 1.4.9
DeepFreeze Continued... - 0.23.6
Saturatable RW - 1.12.1
SafeChute - 2.1.7
ShipManifest - 5.1.4.3
SpaceY Expanded - 1.3.1
SpaceY Lifters - 1.16
StageRecovery - 1.7.2
StationScienceContinued - 2.3
TAC Fuel Balancer - 2.13
ThrottleControlledAvionics - 3.4.2
Trajectories - 1.6.8
TweakScale - 2.3.6
USI Core - 0.4.1
Asteroid Recycling Tech - 0.10.1
USI Exploration Pack - 0.8.1
Freight Transport Tech - 0.7.1
Karbonite - 0.9.1
Konstruction - 0.2.1
USI-LS - 0.6.1
Malemute Rover - 0.3.1
MKS - 0.52.1
NuclearRockets - 0.4.1
Universal Storage - 1.3.0.1
VenStockRevamp - 1.9.5
Waypoint Manager - 2.7
WildBlueTools - 1.20
Mark One Laboratory Extensions - 1.7
Snacks - 1.8
[x] Science! - 5.7

EDIT: Nothing is wrong, nothing is crashing, everything is working as intended. I'm frankly quite disappointed, I was hoping for something to complain about. All these mods, and there's not a single issue.

Edited by Draconomial

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@Draconomial: try adding DeadlyReentry :D

I just see that you got RealPlume-Stock without RealPlume ...

RealPlume-Stock is a collection of patches that need RealPlume to work

Edited by Gordon Dry

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On 2017-06-29 at 0:34 AM, Draconomial said:

I'm about to try playing the ksp_update branch with 128 other mods. I will have no useful bug reports. I might complain anyways. Wish me luck.

  Reveal hidden contents

KSP: 1.3 (Win64) - Unity: 5.4.0p4 - OS: Windows 10  (10.0.0) 64bit
000_AT_Utils - 1.4.4
Toolbar - 1.7.14
USI Tools - 0.9.2
Ablative-Airbrake - 0.2
AutomatedScreenshots - 0.8.0.1
B9 Part Switch - 1.8.1
Chatterer Extended - 0.6.1
Chatterer - 0.9.93.1804
CIT_Util - 1.4
BAM - 1.3
CollisionFX - 4.0
Community Category Kit - 2.0.1
Community Resource Pack - 0.7
CommunityTechTree - 3.1.1
ConfigurableContainers - 2.4.1
Connected Living Space - 1.2.5.3
Crowd Sourced Science - 4.1
DangerAlerts - 1.4
DistantObjectEnhancement - 1.9
DMagic Orbital Science - 1.3.0.10
CapCom Mission Control On The Go - 1.0.2.6
Contract Parser - 1.0.6
Contracts Window Plus - 1.0.8
Progress Parser - 1.0.7
Easy Vessel Switch - 1.3
EVAFuelContinued - 1.5
EVA Struts - 1.0.4
EVA Transfer - 1.0.7
Ferram Aerospace Research - 0.15.8.1
Firespitter - 7.6
Flexible Docking - 1.0.5
FMRS (Flight Manager For Reusable Stages) - 1.2.5
GroundConstruction - 1.2
Hangar - 3.3.2
Interstellar Fuel Switch - 2.6.3
JanitorsCloset - 0.3.2
Kerbal Attachment System - 0.6.3
Kerbin Environmental Institute - 1.2.2.130
Kerbal Foundries - 2.0.2.6
Stork - 0.2.6
Kerbal Inventory System - 1.5
<b><color=#CA7B3C>Kopernicus</color></b> - 1.3.0.4
KSP-AVC Plugin - 1.1.6.2
KSPWheel - 0.9.5.16
KWRocketryRedux - 3.1.4
Infernal Robots - 2.0.11
Mk1-Cabin-Hatch - 0.2
Modular Rocket Systems - 1.13.1
ModularFlightIntegrator - 1.2.4
Monthly Budgets - 2.7
NearFutureConstruction - 0.8.2
NearFutureElectrical - 0.9.1
NearFuturePropulsion - 0.9.1
NearFutureSolar - 0.8.3
Portrait Stats - 1.0.14
Mk2.5 Spaceplane Parts - 1.4.1
RCS Sounds - 5.2
RealChute - 1.4.4
RealPlume - Stock - 0.11.4
Recovery Controller - 0.0.2
ReentryParticleEffect - 1.2.0.1
RemoteTech - 1.8.7
AmpYear - 1.4.9
DeepFreeze Continued... - 0.23.6
Saturatable RW - 1.12.1
SafeChute - 2.1.7
ShipManifest - 5.1.4.3
SpaceY Expanded - 1.3.1
SpaceY Lifters - 1.16
StageRecovery - 1.7.2
StationScienceContinued - 2.3
TAC Fuel Balancer - 2.13
ThrottleControlledAvionics - 3.4.2
Trajectories - 1.6.8
TweakScale - 2.3.6
USI Core - 0.4.1
Asteroid Recycling Tech - 0.10.1
USI Exploration Pack - 0.8.1
Freight Transport Tech - 0.7.1
Karbonite - 0.9.1
Konstruction - 0.2.1
USI-LS - 0.6.1
Malemute Rover - 0.3.1
MKS - 0.52.1
NuclearRockets - 0.4.1
Universal Storage - 1.3.0.1
VenStockRevamp - 1.9.5
Waypoint Manager - 2.7
WildBlueTools - 1.20
Mark One Laboratory Extensions - 1.7
Snacks - 1.8
[x] Science! - 5.7

EDIT: Nothing is wrong, nothing is crashing, everything is working as intended. I'm frankly quite disappointed, I was hoping for something to complain about. All these mods, and there's not a single issue.

Interesting.

Whenever I try to add FAR to my KSP 1.3 it always crashes on launch.

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I read anywhere (!) the following quote that I wisely (?) put into a text file:

Quote

Something about tweakscale-FAR-real Chutes together was what was causing it, remove any one and the problem was fixed.....

 

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8 hours ago, TeeGee said:

Whenever I try to add FAR to my KSP 1.3 it always crashes on launch.

But are you using the development branch?

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3 hours ago, damerell said:

But are you using the development branch?

I'm not sure where to get that version.

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13 hours ago, TeeGee said:

Interesting.

Whenever I try to add FAR to my KSP 1.3 it always crashes on launch.

FAR is simply not compiled to run properly under 1.3.0 so we'll have to wait till a 1.3.0 version is released.

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7 hours ago, Draconomial said:

Why wait for release? Help find and track bugs with the test branch

@ferram4 has requested that the dev build not be linked publicly.

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So I built a concorde replica using tweakscale and Airplane plus parts. I tweakscaled the stock wing parts to shape the delta wing but I noticed something odd and I'm not sure if it's a tweakscale-FAR bug or maybe a limitation of FAR or something.

At lift off, Concorde has a L/D of 4 to 7 and at supersonic cruise, at around 12 (http://www.concordesst.com/concordeb.html). My replica however, is reversed. At liftoff, I have an insane L/D of 22 and at supersonic (Mach 2) of around 6 to 7. My wing area is nearly identical to concorde's (concorde is 358 m^2 and my replica is 402 m^2) so I'm not sure why the L/D discrepancy exists between my replica and the real thing. 

I might be overlooking something since I'm far from an aeronautical engineer. Can someone shed light on this? I'm on 1.2.2 using latest versions of FAR and tweakscale and a bunch of other mods 

Here are some pics:

https://ibb.co/fvO94a

https://ibb.co/e3hacv

Here are logs:

https://drive.google.com/file/d/0B1DFDkTDYdxBZUdBYzJrYXRCRGs/view?usp=drivesdk

Edited by Insanitic
Added logs and pics

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1 hour ago, Insanitic said:

At lift off, Concorde has a L/D of 4 to 7 and at supersonic cruise, at around 12 (http://www.concordesst.com/concordeb.html). My replica however, is reversed. At liftoff, I have an insane L/D of 22 and at supersonic (Mach 2) of around 6 to 7. My wing area is nearly identical to concorde's (concorde is 358 m^2 and my replica is 402 m^2) so I'm not sure why the L/D discrepancy exists between my replica and the real thing.

Concorde used some really cutting-edge techology for its time. If I recall, the wing was shaped with slight droop on the wingtips to catch the sonic boom for increased lift, which is something FAR doesn't model.

That shouldn't affect your takeoff L/D much though. How does your mass compare? If it's much lighter, that would explain the reduced low-speed drag.

Edit: Actually I think I can barely make out the mass in your screenshots as being something like 160t, which is slightly lighter than the real thing's MTOW of 181t, but that shouldn't be enough of a difference.

Edited by Maeyanie

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Warning, long and rambling post ahead...

First off, you're reading the table wrong on ConcordeSST wrong. L/D for Concorde was around 12 in high subsonic cruise at M0.93. In supersonic cruise the L/D is around 7. However that doesn't explain the issue.

Lift

The lift of a wing follows the lift formula where lift is equal to the lift coefficient (CL) x half of density (rho) x true airspeed (V) squared x the wing area (A). Importantly, the lift coefficient Cl includes angle of attack. 

airplane-equation.jpg

In your case wing area does not change. True airspeed is obviously lower at takeoff than in supersonic cruise. Density is higher (unless you're cruising at ground level). Thus higher lift is explained either by higher density or higher Cl.

Drag

The drag equation is very similar, except drag replaces lift and coefficient of drag Cd (in this image just C) replaces Cl. xdrag_force_1.png.pagespeed.ic.uxf7GKtN_

Again, density (rho) is lower in supersonic cruise, while true airspeed is higher. Cd includes angle of attack just like Cd.

 

Angle of attack may be your culprit

Knowing the angle of attack in the various regimes would be useful. Angle of atttack has a massive effect on both lift and drag as you can see in the graph below. (Note the graph is just for a typical airfoil. Wonky stuff happens in the transonic and supersonic regimes.)

Unlike pretty much any other airliner, Concorde did not have high lift devices, making it uniquely dependent on angle of attack to increase lift. This is clear when you look at pictures on approach. Very high pitch angle, which made for lots of noise, high power levels, and the need for the drooping nose to maintain visibility.

Lift_drag_graph.JPG

Ideally, should take density out of the picture by staying at one altitude in all maneuvers. Not the easiest I know.

12 minutes ago, Maeyanie said:

Concorde used some really cutting-edge techology for its time. If I recall, the wing was shaped with slight droop on the wingtips to catch the sonic boom for increased lift, which is something FAR doesn't model.

That shouldn't affect your takeoff L/D much though. How does your mass compare? If it's much lighter, that would explain the reduced low-speed drag.

Edit: Actually I think I can barely make out the mass in your screenshots as being something like 160t, which is slightly lighter than the real thing's MTOW of 181t, but that shouldn't be enough of a difference.

For a given mass, density, wing area and true airspeed you need a given lift. If mass increases with the same speed, density and wing area, angle of attack must increase in order to maintain the same energy state.

Edited by Starlionblue

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5 minutes ago, Starlionblue said:

For a given mass, density, wing area and true airspeed you need a given lift. If mass increases with the same speed, density and wing area, angle of attack must increase in order to maintain the same energy state.

Yeah, I was reversing that assuming (naively) that it was for the same AoA. Since he stated the wing area being similar, and takeoff should be similar density, then the variable of mass being significantly different would have increased L/D. But you're right, AoA is the most variable variable. :)

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7 minutes ago, Maeyanie said:

Yeah, I was reversing that assuming (naively) that it was for the same AoA. Since he stated the wing area being similar, and takeoff should be similar density, then the variable of mass being significantly different would have increased L/D. But you're right, AoA is the most variable variable. :)

"The most variable variable". Love it! :D

Also we have to assume level flight in all these cases since otherwise we have to bring in thrust or weight components. And that's just complicating things.

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9 hours ago, Starlionblue said:

Warning, long and rambling post ahead...

*Snip*

 

Thanks for the informative post. Yeah I got mixed up on the L/D ratios since I was getting conflicting numbers from Wikipedia and that concorde site. 

Yes my plane is lighter than the concorde but the thing is, I don't need to resort to a high AoA (only around 5-10 degrees) to maintain my extremely high L/D of 22 at Mach 0.35 while the concorde needed to at subsonic speeds.

But judging from responses from StarlionBlue + Maeyanie, this discrepancy probably isn't a bug in FAR or on my end.

Admittedly, I haven't revealed everything about my plane.

1. The main wing of my replica is slightly more swept than the Concorde's

2. I implemented a chine towards the front of the nose of the aircraft (like Boom's concept supersonic plane) to adjust the center of lift position.

3. I implemented a swept backside of the main wing, also taken from inspiration from Boom's supersonic plane 

4. I have fuel in the wings using FuelWings, but I also added a fuselage at the underside of the plane. My CoL and CoM are barely touching each other (with CoM in the front of course).

Come to think of it, my replica isn't so much a Concorde replica anymore, but more a Boom Supersonic plane replica hehe.

But do these wing shape differences change the L/D that much? In terms of FAR

Also another interesting note, I've rebuilt my replica's wings with B9 procedural wings and the L/D ratio with those Pwings are terrible at lift off, achieving parity between lift and drag coefficients. Is this a bug with B9 wings?

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Well, I have to admit, I've questioned FAR's drag number recently myself. I built a plane for a suborbital tourist hop mission, using a pair of AJE Su-27 engines, and roughly the same weight as a Su-27 (entirely coincidentally, they look nothing alike). Despite being significantly less aerodynamic (built for high altitude, stability, and hauling big SRBs) it was able to easily supercruise even on the "full drag, strict area rule" hard-mode setting.

Ferram said it's probably legit, and he certainly knows a lot more about this stuff than me, but I was under the impression supercruise was a lot harder to do.

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