Atmosphere still too soupy to anyone else?

[Xavven]

That's so cool Thanks for the video. The presenter is really funny, too.

Yeah, I just realized my previous comment makes no sense for a glider, much less a gliding brick. When I saw his pitch at -20 on final approach I was like 

So, in your KSP shuttle, what is your speed at 10,000 ft (~3,000 m) with a nose down attitude of -20 degrees? They're reading about 290 in what I'm assuming is knots IAS, which would be about 150 m/s. However, we have to convert IAS to TAS because I believe KSP gives you "surface speed", so at 3,000 meters that is 354 knots, or 182 m/s, and that's with speed brakes open.

[Alshain]

How is your landing profile?  You compared to the real shuttle, but the real shuttle practically did a nosedive into the runway and then flared at the end.  It sounds like you are trying to land it on a nice flat glide slope like a plane, the shuttle didn't have enough wing to do that.

Edited September 4, 2017 by Alshain

[ZooNamedGames]

2 hours ago, Xavven said:

That's so cool Thanks for the video. The presenter is really funny, too.

Yeah, I just realized my previous comment makes no sense for a glider, much less a gliding brick. When I saw his pitch at -20 on final approach I was like 

So, in your KSP shuttle, what is your speed at 10,000 ft (~3,000 m) with a nose down attitude of -20 degrees? They're reading about 290 in what I'm assuming is knots IAS, which would be about 150 m/s. However, we have to convert IAS to TAS because I believe KSP gives you "surface speed", so at 3,000 meters that is 354 knots, or 182 m/s, and that's with speed brakes open.

10,000m is around 800m/s. In the upper atmosphere I can't slow down fast enough and when I hit dense atmosphere I slow down too quickly.

24 minutes ago, Alshain said:

How is your landing profile?  You compared to the real shuttle, but the real shuttle practically did a nosedive into the runway and then flared at the end.  It sounds like you are trying to land it on a nice flat glide slope like a plane, the shuttle didn't have enough wing to do that.

I often have to nosedive myself because once I pass under 20km I can't decelerate fast enough and point downwards to minimize life, maximize drag and try to move my velocity downwards towards the runway. Albeit 200m from the runway I generally hold steady before flaring.

[luizopiloto]

My SSTO can sustain mach 1 until sea lvl if I don't do something to reduce speed... And landing that big thing at ~340m/s is not a good idea...
It's the downside of making a craft very aerodynamic... Goes to space faster, but needs some advanced skills when landing... ಠ__ಠ

But some older spaceplane designs have more drag, and If I don't fly it right it stalls and hit the runway a bit more stronger than intended...

[Xavven]

6 hours ago, ZooNamedGames said:

10,000m is around 800m/s. In the upper atmosphere I can't slow down fast enough and when I hit dense atmosphere I slow down too quickly.

I often have to nosedive myself because once I pass under 20km I can't decelerate fast enough and point downwards to minimize life, maximize drag and try to move my velocity downwards towards the runway. Albeit 200m from the runway I generally hold steady before flaring.

Assuming the space shuttle uses ft for altitude and knots indicated airspeed (KIAS) for speed (I don't know for sure), then yeah you're going way faster at that phase of flight.. At about 14:05 in the video you can see them at 32,000 ft (10,000 m) going ~260 KIAS, which is ~426 true airspeed (TAS) at that altitude, and assuming no wind would show up in KSP's groundspeed as ~220 m/s. But you are going 800 m/s at 10,000m, almost 4 times as fast.

How fast are you going in KSP at 3,000m altitude (10,000 ft), though? I'm more interested in your landing because that's where you said the atmosphere seemed too thick for you.

[OhioBob]

There's nothing wrong with the atmosphere.  It's not too thick, it's not too thin, and it hasn't changed since the introduction of KSP 1.0.

If there's a problem it is with drag coefficients.  If there's too much or too little drag, it's because the drag coefficients are too high or too low.  All this talk about the atmosphere is focusing on the wrong issue.

[Dafni]

56 minutes ago, OhioBob said:

There's nothing wrong with the atmosphere.  It's not too thick, it's not too thin, and it hasn't changed since the introduction of KSP 1.0.

If there's a problem it is with drag coefficients.  If there's too much or too little drag, it's because the drag coefficients are too high or too low.  All this talk about the atmosphere is focusing on the wrong issue.

I agree with this

[OHara]

Now, be nice.  The only way to feel the atmosphere is through the lift and drag coefficients, so one cannot tell if the atmosphere is too thick or the coefficients are unrealistically large.  (I suppose one could use the debug menu and compute the density from the dynamic pressure and craft speed.)   The discussion didn't suffer much from not mentioning whether kerbal airs weighs 1 kg/m³.

Other aspects of KSP differ from real aircraft, notably the mass of parts (the 1-man cockpit alone weighing more than a Cessna 172)) and thus the wing loading.  Light single engine aircraft have wing-loading about 70 kg/m²; airliners, 700 kg/m².   I looked through my KSP craft and found from 260 to 1800 kg/m².

The lightest KSP aircraft have numbers more like a learjet, 280kg/m².   Stock KSP lets it takeoff and land at 35m/s, as a Cessna 172 would, but then at cruising speed it flies more like a learjet.    It is helpful to discuss what 'feel' people would enjoy.

Edited September 4, 2017 by OHara

[A_name]

Atmo is just fine IMHO.

[TheEpicSquared]

On 9/3/2017 at 8:04 PM, ZooNamedGames said:

I'm talking about the current atmosphere not the old one.

So am I. 

[Alshain]

2 hours ago, OhioBob said:

and it hasn't changed since the introduction of KSP 1.0.

Not entirely accurate.  It changed many times after 1.0, and on into 1.1.

[OhioBob]

49 minutes ago, Alshain said:

Not entirely accurate.  It changed many times after 1.0, and on into 1.1.

It wasn't the atmosphere that changed.  Squad kept changing physics stuff, like drag/lift coefficients and multipliers, etc.  Since I've been playing KSP (starting with v0.23), there have been only two atmosphere models, pre-1.0 and post-1.0.  And in neither case has the atmosphere been to blame for the drag issues.  Even the old pre-1.0 atmosphere wasn't that bad.

The drag equation:

F_D = ρ v² C_D A / 2

where F_D is drag force, ρ is air density, C_D is drag coefficient, and A is area.

The only thing the atmosphere is responsible for is ρ, and that's never been the problem.  In the current model the values of ρ should be almost exactly those of Earth's atmosphere (except with a 20% reduction in the height scale).

It's the other two variables in the equation, C_D and A, that have kept changing and have been the source of the problems.

In the old "souposhere" days the problem was the area.  Squad used a placeholder formula that computed area based on mass, and which produced absurdly high cross-sectional areas.  It basically turned everything into a flying pancake.  Drag was large because A was large, not because the atmosphere was too thick.

Since v1.0, Squad seems to have come up with a reasonable way to compute area, so that's not a problem anymore.  And they now have a realistic atmosphere model, which I'm almost certain hasn't changed since its release.  All the post-1.0 tweaking appears to have all been to either coefficients or global multipliers.

[RoadRunnerAerospace]

I like to call the atmo "the souposphere"

[luizopiloto]

5 hours ago, OhioBob said:

There's nothing wrong with the atmosphere.  It's not too thick, it's not too thin, and it hasn't changed since the introduction of KSP 1.0.

If there's a problem it is with drag coefficients.  If there's too much or too little drag, it's because the drag coefficients are too high or too low.  All this talk about the atmosphere is focusing on the wrong issue.

No... It changed 3 times since 1.0...
1.0.1 was too thin, and some inexperienced players was having problems during reentry because their descent profile was too steep and the capsule was hitting the ground above mach1 with no way to safely deploy their parachutes.
1.0.2 devs tried to help but made the atmosphere way too dense, making all previous SSTO designs unusable...
1.0.5 atmosphere was balanced to what we have today...
1.2.0 devs changed the way aerodynamic simulation works to something similar to an old mod called NEAR, a simplified version of FAR, where the shape of the craft affects drag, lift and body-lift... and is what we have today.

[Alshain]

1 hour ago, OhioBob said:

It wasn't the atmosphere that changed.  Squad kept changing physics stuff, like drag/lift coefficients and multipliers, etc. 

You do understand that drag and lift coefficients, among other things are what the player base refers to when they say "atmosphere"?  This OP is about exactly that.

[OhioBob]

2 minutes ago, Alshain said:

You do understand that drag and lift coefficients, among other things are what the player base refers to when they say "atmosphere"?  This OP is about exactly that.

Yes I do understand that.  And it's technically wrong.  If we're talking about lift and drag coefficients, then why not just say that.  I've never found it acceptable to knowingly use incorrect terminology.

[Alshain]

Just now, OhioBob said:

Yes I do understand that.  And it's technically wrong.  If we're talking about lift and drag coefficients, then why not just say that.  I've never found it acceptable to knowingly use incorrect terminology.

Because it is all related and people don't know the difference.  Atmosphere is used as a generic term to refer to "not vacuum".  It's not just here either, the actual game does this.

[OhioBob]

5 hours ago, luizopiloto said:

No... It changed 3 times since 1.0...
1.0.1 was too thin, and some inexperienced players was having problems during reentry because their descent profile was too steep and the capsule was hitting the ground above mach1 with no way to safely deploy their parachutes.
1.0.2 devs tried to help but made the atmosphere way too dense, making all previous SSTO designs unusable...
1.0.5 atmosphere was balanced to what we have today...
1.2.0 devs changed the way aerodynamic simulation works to something similar to an old mod called NEAR, a simplified version of FAR, where the shape of the craft affects drag, lift and body-lift... and is what we have today.

Yes, changes were may to the drag physics, but it wasn't the atmosphere model that changed.  The atmosphere is responsible for only 1/4 of the variables that go into the drag calculation.  So why does everyone assume it's the atmosphere that changed whenever drag changes?
 

5 hours ago, Alshain said:

Because it is all related and people don't know the difference.

And I'm trying to explain the difference.  I find it quite disturbing that I'm being chastised for trying to educate people.
 

Edited September 5, 2017 by OhioBob

[adsii1970]

2 minutes ago, OhioBob said:

Yes, changes were may to the drag physics, but it wasn't the atmosphere model that changed.  The atmosphere is responsible for only 1/3 of the variables that go into the drag calculation.  So why does everyone assume it's the atmosphere that changed whenever drag changes?

Because since .90 (beta than ever) it has remained the easiest target - blaming Squad. Not meaning to stir the pot, so to speak, but the charges of the atmosphere. the water/ocean, and the physics  within the game remain easy targets for those who demand 100% realism in the game. Somehow it has been forgotten that it is a game meant to be enjoyed and not a totally accurate space simulator...

And that's all I've got to say about that... in the words of Forrest Gump.

[Alshain]

4 minutes ago, OhioBob said:

And I'm trying to explain the difference.  I find it quite disturbing that I'm being chastised for trying to educate people.

I find it quite disturbing that you would tell people that using the terminology the game uses is improper.

[OhioBob]

1 minute ago, Alshain said:

I find it quite disturbing that you would tell people that using the terminology the game uses is improper.

Where does the game say that post-1.0 changes in lift and drag were because the atmospheric model changed?

[Alshain]

1 minute ago, OhioBob said:

Where does the game say that post-1.0 changes in lift and drag were because the atmospheric model changed?

In the tutorials, when it describes craft going through the atmosphere.

[OhioBob]

1 minute ago, Alshain said:

In the tutorials, when it describes craft going through the atmosphere.

That's unfortunate.  Which tutorial?

[Alshain]

2 minutes ago, OhioBob said:

That's unfortunate.  Which tutorial?

I don't recall off the top of my head.  It's been a while.  It had to do with reentry though.

[SamBelanger]

On 02/09/2017 at 10:56 PM, ZooNamedGames said:

I have spent time since .25 refining my Saturn Shuttle (and still continue to) but one of my biggest problems is that I lose so much speed during the final moments of the landing that I can almost stall moments before touching down with less than 20m/s remaining. Which I find not only problematic (as it's stall speed is far above that so stall to that extent is catastrophic or possibly even fatal). In reality the Space Shuttle landed at 214 miles per hour (344.4 kmh) or ~95.6m/s (on the low end). Whereas I end up landing at highway speeds of 44 miles per hour (71.9kmh).

Understanding this takes place on a unrealistically small world with vastly simplified physics but I still have to wonder-

Am I the only one who thinks the atmosphere is still too thick?

Or are there players out there who find the game perfectly suitable, making me into a raving madman? Or do others agree?

_{^{Ps- I am aware there are mods to solve my problem however I am a vanilla kinda guy and more importantly feel that it's a lingering stock problem that should be resolved... again.}}

Discuss

I agree that there is something missing in this subject ''atmosphere'' and in addition, the game Kerbal Space Program improves every time when has an updates 

Edited September 4, 2017 by SamBelanger
:)