wings and lift? How much?

[Arugela]

Do wings inside of a space planes other parts get blocked from producing lift? Say If I put a part on the side of soemthing and push it in for visual effects will it reduce the lift? And how much lift do you want for a plane. I'm assuming it's related to wing loading per weight.

[Dafni]

Clip away! Last time I checked wings etc produce lift (and airbrakes etc produce drag and all that) even when they are fully occluded, by say a fuel tank or whatever.

(as far as I am aware the only exception is if you attach stuff to the inside nodes of cargo bays or service bays)

 

Cant tell you how much lift you want per weight, depends on the kind of plane you are building-

Edited October 17, 2018 by Dafni

[Rocket In My Pocket]

Wings still add lift so long as they aren't in a dedicated cargo or service bay.

So yes, you can add lift by clipping wings into body sections.

Depends what you are doing with said plane? There isn't really an easy catch all answer here, you want enough to lift the plane comfortably without going overboard. It's something you'll get a feel for over time, in the aviation industry they have a saying; "If it looks right; it is right." So make it look right, and you should be fine!

[Arugela]

Any idea how to easily get your wings to not break off when pulling up after nosing down to get over 400m/s with rapiers? I have a plane that can get up to 1555m/s on jets, but I have problems with plane breakage pulling up after nosing down tog et 400m/s.

Still trying to figure out if it's a physics break from rigid attachment or if it's a problem with actual structure. I only have rigid attachment atm on parts with no lift. Unfortunately it's a massive 700 part plane and very laggy to test. 8)

Edited October 17, 2018 by Arugela

[Dafni]

Nice one @Rocket In My Pocket ! You posted right when I edited the cargo bay part in

[Rocket In My Pocket]

Are you trying to get to space?

The Rapiers work best around 10k typically, that's where you'll want to do your "run up" to Mach 3-4ish before heading to space.

Ideally you shouldn't have to dive to gain speed, however autostrutting the wings will help during high G maneuvers certainly.

[Arugela]

I'll try doing it at higher altitude then. I was nosing down to get 400m/s around 1500 meters. It may be too many forces on the wings then.

 

Edited October 17, 2018 by Arugela

[Rocket In My Pocket]

7 minutes ago, Dafni said:

Nice one @Rocket In My Pocket ! You posted right when I edited the cargo bay part in

Lol, I think we posted at the exact same time. Like some kind of double ninja "jinx" lol.

5 minutes ago, Arugela said:

I'll try doing it at higher altitude then. I was nosing down to get 400m/s around 1500 meters. It may be too many forces on the wings then.

It helps to right click the engine and pin it's tab open. (Even if you have multiple engines you only need one pinned.) Then you can watch the power output as you climb, somewhere around 10k give or take a "k" depending on your design; you're going to find the sweet spot of maximum power for the Rapier. That's where you'll want to stay until you are ready to climb to vacuum. The power output also increases as speed increases to a certain point, so by staying in the ideal height band, you should be able to accelerate to Mach 3-4 if you have enough TWR. Just be wary of parts overheating at that point!

Edited October 17, 2018 by Rocket In My Pocket

[Arugela]

I have an odd setup with 64 rapiers and 64 whiplash. This is stacked with 64 nukes and 64 toroidal engines... For an aircraft at 2880 tons max. (It's my attempts at 1k cargo to orbit. And in this case anywhere if I get the mining drones in it and get it to minimus.)

It was looking like I was previously loosing speed after like 5k so I was trying to gain initial speeds by gaining it early. This was probably the mistake.

I may have to actually do a non 1:1 engine for everything at one point to reduce parts counts. I tend to do this to make the craft easy to fly or design(and test out the engine combo) but it may be eating parts count.

BTW, here is the oversized tub of cargo!

Edited October 17, 2018 by Arugela

[Rocket In My Pocket]

Wow, she's huge!

You may be climbing too fast if you are losing speed? What kind of ascent slope are you doing? Like 5-10 degrees?

I've never designed an SSTO that big myself, so you may be facing issues I'm not considering!

[Arugela]

I normally fly it with the nose pointed at 10 degrees and the actual path at 5 degrees. Although I'm setting it up this flight for 15/10... Atlhough it seems to be telling me otherwise. Waiting to see where it lands after I stopped holding up.

It seems to have stopped around 15/7.5 degrees.

Now I just have to wait 30 minutes or less for my pizza to arrive my spaceplane to make it to higher altitude to see if I can get her up to speed.

Edit: the prograde keeps dropping and is settling at around 5-6 degrees while my nose is staing at 15. 10/5 may be optimal for this craft. I'm currently maintaining 230m/s while at 10/5 it's normally around 330m/s. I was probably flying efficiently on previous attempts. Just have to actually climb to try to get my rapiers up to speed at lower air density.

Slightly cock-eyed at 15 degrees nose. It seem to be protesting this much angling. I will definitely keep it at 10 degrees later as it always maintains the 5 degrees prograde.

Edit2: The nose is attempting to settle back to 10 degrees on it's own. It seems to be agreeing with me.

Edited October 17, 2018 by Arugela

[Rocket In My Pocket]

Hmm...y'know it just occurred to me that your timing may just be bad, I think 1.5 introduced some kind of bug with drag? I remember hearing something about it.

[Arugela]

This is how it flew in previous versions. I actually had a weird drag but that can still pop up if you go back to launch or other weird things. It will get a single very long drag line in a certain part. I just have to back to the VAB and restart to reset it. You can tell if the drag line is going to be there on this plane at 90m/s. It will pop out before the normal drag lines for the cargo bay bodies which pop out at the same time at 120m/s. I wonder if it's the same bug. If it is it's been around for a while and I think is more likely on absurdly large laggy craft.

I think cupcake was complaining about a drag but with cargo also a while back. But that was a previous version.

Edit: restarting my flight because I nosed up too high and it caused the plane to angle and loose efficiency and nose down.

Edited October 17, 2018 by Arugela

[Rocket In My Pocket]

It's something about body lift not being calculated correctly, only wings give lift right now. (I think?)

So you might be missing a bunch of lift you'd otherwise have.

This may be a particularly bad time in KSP's development to build the worlds largest SSTO lol. Squad said they are looking into it though, hopefully hot fix soonish.

 

Edited October 17, 2018 by Rocket In My Pocket

[Arugela]

I'll watch the lift. I think It had the teal lines for stuff, but I don't now how much it should have. And I don't know if the middle cargo bays were getting any.  Should the cargo bays be producing lift? I'll get a pic when I get back into the air.

Yea if that's an issue hopefully that will be resolved. I'm years behind finishing this craft(started with the original version in probably 1.2-1.3). I keep running into bugs that get in the way. It's like the game just doesn't want me to finish this craft.

Yea, It doesn't seem to be holding like it did only like a week ago. Which is odd because it was already in 1.5.0.2332. Maybe the patched the bug in?! That or I am missing something. It's hard to tell.

MK2-MK3 adapters aren't producing any. Assuming they should. I'm not entirely sure what should be doing it. I may need to get higher to see if the teal lines pop out.

Edit: My ship seems to have gotten back to it's normal flight. From what I understand of it(for now). If there is a drag bug it probably wouldn't hurt as it means better lift if it's fixed. 8)

Of course I didn't fly it much before 1.5 and the last time I played before 1.4... It was blowing up because I had Rigid attachment on the wrong parts and it was blowing up while trying to get off the runway. I may not have a proper comparison now. More lift from a bug fix would be fantastic though. Edit2: The prograde does seem to keep dropping. 8/ Hopefully it doesn't drop back to negative flight again.

Edited October 17, 2018 by Arugela

[AeroGav]

43 minutes ago, Arugela said:

I normally fly it with the nose pointed at 10 degrees and the actual path at 5 degrees. Although I'm setting it up this flight for 15/10... Atlhough it seems to be telling me otherwise. Waiting to see where it lands after I stopped holding up.

It seems to have stopped around 15/7.5 degrees.

Now I just have to wait 30 minutes or less for my pizza to arrive my spaceplane to make it to higher altitude to see if I can get her up to speed.

Edit: the prograde keeps dropping and is settling at around 5-6 degrees while my nose is staing at 15. 10/5 may be optimal for this craft. I'm currently maintaining 230m/s while at 10/5 it's normally around 330m/s. I was probably flying efficiently on previous attempts. Just have to actually climb to try to get my rapiers up to speed at lower air density.

Slightly cock-eyed at 15 degrees nose. It seem to be protesting this much angling. I will definitely keep it at 10 degrees later as it always maintains the 5 degrees prograde.

Edit2: The nose is attempting to settle back to 10 degrees on it's own. It seems to be agreeing with me.

You don't want the nose getting more than 5 degrees above prograde as the drag gets to be horrendous.    When you are no longer producing enough lift with nose 5 degrees above prograde and the climb starts levelling off, is when you will hopefully transition to supersonic flight.     If it is unable to do so, you either have not enough power, too much drag,  or not enough lift, because if you had more lift you could have done the supersonic transition at a higher altitude.

Too much wing causes problems for your air breathing engines.   You will either have to run a lower angle of attack than optimal,  or find yourself getting up to altitudes where the engines can't make good power before they've maxed out mach number wise.      A space plane that climbs to orbit with chemical engine power also has a TWR well above 1 in rocket mode, so lift to drag ratio in rocket mode doesn't matter as much as getting dry mass down.

NERV powered space planes have much less power in rocket mode and very heavy engines, they need a lot more wing and a good lift to drag ratio in hypersonic flight.

@Arugela  I strongly recommend you install Kerbal Wind Tunnel

It gives you a nice graph showing excess thrust at every speed and altitude,  showing you when  you can get supersonic

note

- it only takes account of engines on the first stage

- it takes account of landing gear drag so you need to raise them before running the analysis

- does not take account centrifugal effect from very high speed flight that reduces your apparent weight as you get up near orbital speeds

- it works in 1.5 just with the odd  hang, like it did in 1.4x

[bewing]

1 hour ago, Arugela said:

BTW, here is the oversized tub of cargo!

Looking at your pic, it looks like you have one set of engines right in front of the other set. This almost certainly means that your entire front set of engines is producing a grand total of zero thrust. Which is almost certainly why you are having problems making the thing go.

 

[Arugela]

I think I have the engines setup so they don't block thrust. I could be wrong though.

if anyone is interested.

File: https://www.dropbox.com/s/l2n9kft6vbsxe1s/KB-52 1_5_0_2332 x64.craft?dl=0

This is what I am currently flying. And, yea, I think it's missing lift. That or I was flying a version with x88 engines and it was getting over the problem. Started loosing altitude around 3k+. I know this used to get up easier than this. I'm hoping there is missing lift at this point. I'm trying to optimize this to get under 700 parts. While keeping this engine design that is. It's weird thing I do with my spaceplanes at this point.

Do any of those mods measure actual output of the engines to see if it's blocking thrust?

Edited October 17, 2018 by Arugela

[AeroGav]

25 minutes ago, Arugela said:

I think I have the engines setup so they don't block thrust. I could be wrong though.

if anyone is interested.

File: https://www.dropbox.com/s/l2n9kft6vbsxe1s/KB-52 1_5_0_2332 x64.craft?dl=0

This is what I am currently flying. And, yea, I think it's missing lift. That or I was flying a version with x88 engines and it was getting over the problem. Started loosing altitude around 3k+. I know this used to get up easier than this. I'm hoping there is missing lift at this point. I'm trying to optimize this to get under 700 parts. While keeping this engine design that is. It's weird thing I do with my spaceplanes at this point.

Do any of those mods measure actual output of the engines to see if it's blocking thrust?

Blocking thrust is an "all or nothing" phenomenon.  So if you think the front engines are being blocked, activate only those engines on the runway and see if the craft moves.

the inboard engines appear to be blocked by the rear wing cluster.

btw  i'd change those mk2 fuselage pieces for 2.5m, which have less drag and hold more fuel

Edited October 17, 2018 by AeroGav

[Arugela]

Lift is back on body parts:

After getting nicely up to above 333km/s it is now flying with the nose at the top of the prograde circle. So, hoepfully this will get up into orbit correctly.

Edit: I've added some more engines and control surfaces. I've got this thing flying pretty stably. But is it likely these canards introduce anything odd into my roll authority?

This pic is after almost getting to orbit. I made some early mistakes and didn't use trim when I should have and messed up from manually pulling up and a few other things. But it was a fairly good flight. I think I can get it into orbit after I put the SAS modules on it and fly a little more efficiently. I burnt way too much fuel early on.

Edited October 25, 2018 by Arugela