Stable Glider Challenge: Make a glider that flies really efficiently, all by itself.

[g00bd0g]

My Entry. Numbers below apply to both controlled and free categories. I could bump my "controlled" numbers a bit by using SAS, but I feel it's cheaty... FAR would be fun, I think we could get over 50-1 LD... Maybe even 70-80...

L/D = 24.120

Min Sink Rate = 2.115

Still room for improvement...

https://kerbalx.com/download/craft/34733

 

 

[Snark]

Aaaand, we have some new entries!  I've updated the leaderboard.    (Thanks for your patience, everyone-- I know it's been a few days since I've come here to keep things up to date.)

New since last update:

• @qzgy had a new and improved entry.  I've updated the leaderboard to show your best shot.  (I've decided to limit the leaderboard to one entry per person, so if you outdo yourself, I'll just update your record rather than inserting a second one).
• New entry from @Steel Starling, taking the lead in the "controlled" category for both glide ratio and rate of descent.
• New entry from @g00bd0g, taking the lead in the "free" category for both glide ratio and rate of descent.

Excellent work, guys! 

A few odds and ends:

On 9/22/2017 at 9:30 PM, Steel Starling said:

Sorry, couldn't figure out how to get my images into the comment itself, inserting the URL into the insert media tab wasn't working properly.

For future reference, the way you do this is to don't try to "insert media", the forum is flaky about that.  Instead, just paste the image URL directly into your post, as text.  When you do this, the forum will detect it and will automatically replace it with an inline image.  Note that when I say "image URL", I mean literally the URL of the image itself, not the page where it resides.  Thus, for example, suppose you have an image on imgur.  What you want is not the URL of the imgur page.  Instead, open that imgur page in a browser, right-click on the image, and choose "Copy Image Location".  That is the URL you want.  It's important that the URL has to end in an image extension, such as .png or .jpg, because that's how the forum recognizes that "this is an image and I should do the automagic thing".

16 hours ago, g00bd0g said:

Does anyone know if wing Kerbal aerodynamics takes Aspect Ratio or wing thickness into account?

I believe that the answer is no.  (Not 100% sure about that, but that's what I think.)  I believe the way it works is that the wing has certain numbers for lift and drag baked into it via the config file, and that's what gets used regardless of the visual appearance of the wing.

That's just a guess, though-- I'm not totally sure about it.  (I'm generally not an airplane guy and rarely fly them, so I'm really not an expert in this area.  Kind of ironic, I suppose, given the challenge I chose to post here.) 

16 hours ago, g00bd0g said:

Additionally how does KSP deal with aero of "clipped" parts?

Simple:  It doesn't.  Stock KSP aerodynamics has zero awareness of clipping, or of the relationship of parts to other parts.  For example, if you radially attach a part to your plane, it will generate drag regardless of its physical location-- for example, if you use the offset tool to move it physically inside the fuselage, it will still generate exactly as much drag as if it were still bolted on to the outside, in spite of the fact that it looks like "this should generate no drag because it's inside something".    Similarly, if you built a rocket with a pointy nose cone mounted neatly on top of the rocket, and then you use the offset tool to slide it down inside the rocket so that the blunt flat front end of the rocket is exposed, you would think that this would kill your aerodynamics, but it doesn't; as far as the game is concerned, "oh look, there's a nose cone attached to the top of the rocket," and you'll get exactly the same good streamlining and won't hurt your drag at all.

Basically, what it boils down to is that all the game cares about is "where is the part attached," not "where is it physically located".  Clipping only affects the cosmetic appearance of your plane, not its aerodynamics at all.

[EpicSpaceTroll139]

On 9/30/2017 at 9:58 AM, Snark said:

<snip>

I believe that the answer is no.  (Not 100% sure about that, but that's what I think.)  I believe the way it works is that the wing has certain numbers for lift and drag baked into it via the config file, and that's what gets used regardless of the visual appearance of the wing.

That's just a guess, though-- I'm not totally sure about it.  (I'm generally not an airplane guy and rarely fly them, so I'm really not an expert in this area.  Kind of ironic, I suppose, given the challenge I chose to post here.) 

 

Simple:  It doesn't.  Stock KSP aerodynamics has zero awareness of clipping, <snippity snip>

I can mostly confirm this from experience. A 2x1 straight wing behaves the same as a 1x2 straight wing which behaves the same as a 2x2 Delta wing. Doesn't matter if your wings are stacked either. 4 1x½ wings stacked to look like a brick will give you the exact same lift and drag as a 1x2 wing... Kinda disappointing really. A SSTO can have same wing planform as an early biplane and fly just as well as if it were designed with proper streamlining.

I also concur on the clipping of parts.

Anyways, I might try my hand at this challenge sometime. Juggling projects right now lol.

[michal.don]

Gliding? In a space sim? I never thought I'd be doing that, apart from reentering a shuttle.... But I had a great time, it was fun doing something new.

My ususal design approach is KISS - "keep it simple, stupid!" , which probably comes from my old computer suffering horribly whenever part count approached triple digits. My new computer handles larger crafts well, but the habit survived.

A plain and simple craft, 26 parts, and pretty decent numbers - ratio of 26,526, and lowest descent while in controlled glide of 1,750 m/s.

And the craft is capable of landing in water.

Now I think I might put KJR back in my install, and try to do something large, and maybe with procedural wings, and see if I could push those numbers just a tad higher.

Thanks for the challenge,

Michal.don

[adsii1970]

Folks, I will be finishing the badges up next week and sending them off for @Snark's approval. I forgot the last week and this week were mid terms...

[cratercracker]

@Snark

Made a patch for this challenge.

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"Pull the trigger'

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Your welcome!

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P.S uploading from imageShaack and google pictures, please save the patch on your computer, rather than copy paste it, it might not be available soon.

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[no_intelligence]

Hey guys, as I'm a real glider pilot, i thought i might enter into this 

So, her is my first glider, built in KSP:

Ratio of 26,308 and sinkrate of 1,920 in controlled flight. Seems that these values are actually really good I think!

Design is a bit ugly but practical. Only problem: didn't manage to land it it one piece yet. But the cockpit always stays intact, so Jeb survives...

https://kerbalx.com/no_intelligence/Ultra-Glider

 

Edit: managed to land it safely without any destruction on water 

 

Edited October 7, 2017 by no_intelligence

[adsii1970]

Looking for opinions... this is the first chance to sit and piddle since I was asked...

These are some working drafts of ideas for the signature badge Snark asked me for. Any final design will have the three categories @Snark has provided. Feedback is wanted (and needed).

The first version is pretty simplistic. But I felt something wasn't quite right.

The second image is a little more complex, but still not sure...

[cratercracker]

@Snark                   (don't know if that is a repost, i just forget wether posted here or not)

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"This is what we live for"

200-150

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Your welcome!

 

[Snark]

Hi everyone!  I apologize for the slow responses lately-- IRL has been super busy. 

Thanks to @michal.don and @no_intelligence for your entries!  I'll update the leaderboard.

Appreciation for the badge work, too, @cratercracker and @adsii1970.  My personal preference is for @adsii1970's second one.  I have no suggestions to offer for improvement, largely because I'm utterly without artistic talent myself, and that one's already far better than anything I myself could have come up with.    (Maybe get rid of the silver KSP logo up top where it's on the star-and-wings?  I mean, we all know we're playing KSP, and it's a little hard to read at that small size anyway.)

 

[adsii1970]

42 minutes ago, Snark said:

Hi everyone!  I apologize for the slow responses lately-- IRL has been super busy. 

Thanks to @michal.don and @no_intelligence for your entries!  I'll update the leaderboard.

Appreciation for the badge work, too, @cratercracker and @adsii1970.  My personal preference is for @adsii1970's second one.  I have no suggestions to offer for improvement, largely because I'm utterly without artistic talent myself, and that one's already far better than anything I myself could have come up with.    (Maybe get rid of the silver KSP logo up top where it's on the star-and-wings?  I mean, we all know we're playing KSP, and it's a little hard to read at that small size anyway.)

 

Ok, will work on it this week. Should have the images for you ready to download soon. ^TM

[cratercracker]

All the odds mods are against me. 

[ZooNamedGames]

Might be interested in this since I've had a track record to always add more lift than the drag I create leading to stalls only occurring under 20m/s. So for once I might have a fair chance.

[Mr. Peabody]

I will try this the next time I get a chance. Famous last words.

[KerbalTween]

So Your saying a space shuttle Test (If you don`t include the Mk1 Cockpit)