TiktaalikDreaming

[WIP] German WWII rockets including never built absurdities

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Yeah, pretty much everyone drastically underestimated heating (and overestimated lift) at hypersonic speeds. And that's true even for the very low-wing-loading Von Braun 1948 and 1952 studies. (Which, incidentally, is more reason to think Scott might be right that the whole A-9/10/11/12 scheme might be a backport of the 1948 one, rather than something genuine at the time--after all, even by the mid-late war it was clear that the A-9's "wing" design would do next to nothing).

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28 minutes ago, NathanKell said:

Yeah, pretty much everyone drastically underestimated heating (and overestimated lift) at hypersonic speeds. And that's true even for the very low-wing-loading Von Braun 1948 and 1952 studies. (Which, incidentally, is more reason to think Scott might be right that the whole A-9/10/11/12 scheme might be a backport of the 1948 one, rather than something genuine at the time--after all, even by the mid-late war it was clear that the A-9's "wing" design would do next to nothing).

Yep.  And the proliferation of wild loony wing designs tested for the A-9 shows they were aware it wasn't working.  I've done some testing with a fairly badly formed A-9 wing in KSP.  It models the "doesn't work" quite nicely.  :-)

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Happily, however, the 1948* and 1952 designs do work. :)

* Suborbital only; but given X-15 rated shielding it would presumably be fine. LV.

Apologies for spamming, but I figured those are relevant here. :D

That reminds me. @TiktaalikDreaming I really need to actually, like, try this stuff out. And, gnu help us, place/price it in RP-0. :D

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3 minutes ago, NathanKell said:

Happily, however, the 1948* and 1952 designs do work. :)

* Suborbital only; but given X-15 rated shielding it would presumably be fine. LV.

Apologies for spamming, but I figured those are relevant here. :D

Slightly more wing than SaJdNWo.png
(That's the only shot I have on imgur of my A-9 parts, so the only one I can get to at work)

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4 hours ago, NathanKell said:

@TiktaalikDreaming: yeah, even A-4b levels of wing are next to nothing compared to what 5-6t of mass requires...even with X-15 level alloys.

Something tells me they were hoping for lift to keep progressing the same as it did for subsonic, so very little surface needed.  It does look nice and sleek and sexy.  While it nose dives into the ground.

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Notes for 1.1 based on prerelease;

The parts all seem to work as well as they ever did.  There's no intrinsic plugins required, there's no legs or wheels.  There's requirements to have the system function using realistic fuels (depends on RealFuels, Community Resource Pack, and ModuleManager), but without module manager, the included config will do nothing.  I suspect a lot of parts mods will be in this situation. 

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OK, I have noticed in 1.1 there's one teeny detail missing.  Radio.  Seeing as the fins I chose for this are the ones with antennae poking out the back, I'm adding some ModuleDataTransmitter to those parts, testing, then I'll be uploading a version that won't need radio dishes attached to it.

OK, maybe I had kerbalism installed without remembering and you don't actually need antennae to use an unmanned pod.  I'll be adding the antennae anyway, but not so much in a rush now.

Edited by TiktaalikDreaming
derp

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I've noticed a bit of problem while using this. I understand that it is a work in progress, so this is to be expected, but this seems a bit big. I'm playing a well modded career mode, and when I try to launch this, the Oxidizer drains much faster  than it should, leaving at least a third of the liquid fuel.

My list of mods is:

- Chatterer

- Community Resource Pack

- Kerbal Attachment System

- Kerbal Construction Time

- Kerbal Engineer

- Kerballoons

- Kerbal Inventory System

- KRASH

- Final Frontiers

- Procedural Parts

- Strategia

- Trajectories

- Kerbal Alarm Clock

- Sounding Rockets

and this.

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4 hours ago, Panel said:

I've noticed a bit of problem while using this. I understand that it is a work in progress, so this is to be expected, but this seems a bit big. I'm playing a well modded career mode, and when I try to launch this, the Oxidizer drains much faster  than it should, leaving at least a third of the liquid fuel.

My list of mods is:

- Chatterer

- Community Resource Pack

- Kerbal Attachment System

- Kerbal Construction Time

- Kerbal Engineer

- Kerballoons

- Kerbal Inventory System

- KRASH

- Final Frontiers

- Procedural Parts

- Strategia

- Trajectories

- Kerbal Alarm Clock

- Sounding Rockets

and this.

 

Yeah, I've been meaning to fix that. My numbers are just off. At first I thought it might have been something to do with the mods I had installed but it happens even with no other mods installed. 

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Looking a bit closer, I can see you're right. The fuel to oxidizer ratio is 11/9 rather than 9/11. It's a pretty quick fix, I just changed the oxidizer amount to 151.25.

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Hey, I've been using this mod for a while, and I've never expressed my appreciation for it.  So, here goes...THANKS!  I use this especially with the mod "Historic Missions", for the early missions.  Good job, and thanks again for creating it.

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3 hours ago, jcddmdad said:

Hey, I've been using this mod for a while, and I've never expressed my appreciation for it.  So, here goes...THANKS!  I use this especially with the mod "Historic Missions", for the early missions.  Good job, and thanks again for creating it.

On a related note, I'll be adding in the first of the Redstones, the A6 NAA-75-110.  Still massively smaller than the A-10 piece of wishful thinking.  :-)

I still need to add Wernher's really dumb, vane-based "gimballing" and a shroud, but I did up the model in a sort of limbo state of not knowing where to put it.  So I decided to add it to this mod rather than just expiring it.

cstVMPu.png

Edited by TiktaalikDreaming

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3 hours ago, Panel said:

Looking a bit closer, I can see you're right. The fuel to oxidizer ratio is 11/9 rather than 9/11. It's a pretty quick fix, I just changed the oxidizer amount to 151.25.

Yep.  Looks like I got confused with Oxy vs Fuel ratios when copying it in due to the Real Fuels config using 75% Ethanol.  The ethanol fuel ends up being consumed faster than the oxidizer, contrary to virtually every other combustion system ever, mostly due to that 25% water in it.  Will fix shortly.

Damn, I thought I posted the above about a day ago.  Updated with the issue fixed.  Thanks for the reminder

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V0.10 is uploaded.  This includes the fix for the stock fuel on the A-4 tank being deranged, and colour switching between the test pattern and a dodgy green thing.  It also now includes that Redstone first stage A-6 NAA-75-110 engine, with shroud, winglets and a fuel tank.  The texturing on the fuel tank is the base layer, I don't think there was ever a plain whitish Redstone rocket, although there were some not far from it.

Just a quick note on scale.  I usually do all my KSP historical pieces at half scale.  There's a bunch of reasons for that, but basically Kerbals are small, and so is Kerbin.  But, half scale for the Redstone is a diameter of a bit under 0.9m (nominal body diameter was 5'10" in dodgy units).  The A-4 is slightly smaller again.  This means nothing lines up with stock parts.  So, I'm considering making these match a stock size, just for part compatibility.  More for the Redstone than the A-4, which doesn't really need to match anything.

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uploaded the update, and my rocket made atmo-escape speed and trajectory...which was hard with the fuel mix unbalanced.  I was surprised!  Thanks for that update.  I tried the Redstone and included shroud/winglets.  I noted that the winglets attachment points didn't snap to the related attachment points on the shroud.  I used the symmetry Tool to place them correctly.  I'm doing some research on the engine now, since I've not heard of it before. 

Edited by jcddmdad
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2 hours ago, jcddmdad said:

uploaded the update, and my rocket made atmo-escape speed and trajectory...which was hard with the fuel mix unbalanced.  I was surprised!  Thanks for that update.  I tried the Redstone and included shroud/winglets.  I noted that the winglets attachment points didn't snap to the related attachment points on the shroud.  I used the symmetry Tool to place them correctly.  I'm doing some research on the engine now, since I've not heard of it before. 

The difference of being able to use the last 20% of propellant mass is noticeably huge.  :-)

With the winglets, there's something weird going on with them.  They were working on my dev install, then after updating, I installed on my test game, and they wouldn't attach.  I found if I rotated them, then surface attached, detached, then they'd stack node attach.  Don't know if it's a game bug or a part issue.  A bit annoying. 
There's no way around them being separate parts though.  Only one control surface and one lifting surface per part.

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Rescale poll.  0.5 or 0.7?  Screen shots of 0.5 and 0.7 rescale.  Very clearly the 0.7 rescale fits existing 1.25m parts much better because it's scaled to match 1.25m.  The 0.5 scale is just scaled to 0.5.

 

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7 hours ago, halowraith1 said:

whats happening with the A-10?

It's being annoying.  Or, it's fit between stages is being annoying.  But mostly it hasn't been looked at for a while due to other factors.

 

EDIT:
Just had another look at my blender file.  Issues to resolve: The wing.  I have a sketch level drawing of it showing the interior structure of the wing, and it looks like it didn't have control surfaces (aka aileron/rudder/etc)  But, there's what looks like pipes leading to exhaust nozzle looking structure.  So I'm wondering if I'm looking at steam based RCS nozzles in the wing (exiting the tail edge).

Secondly, the arrangement for the A-4 upper stage is nuts.  It'll work, but I expect a 50% chemically assisted rapid disassembly on stage separation.  The upper stage nestles inside the fuel tank of the first stage, which comes up around the fin structure of the A-4.  Because fins are excellent on second stages.  :-)  But the gimbal vanes on the A-4 are part of the fin structure, so no fin = no gimbal = zero control.

Edited by TiktaalikDreaming

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OK, for the record, this is the main issue with the A10 booster.  The upper fuel tank has an inset hollow space for the A-4.  I've been trying to think of a way around this, but I think I'll just make it as per daft original plans and see what proportion of separations result in rapid catastrophic disassemblement.  So, the top half of the tank has both a tapered cone to fit the A-4 body, and four radial cuts to fit the wings.  In the linked album, the first two shots look like a perfectly normal rocket.  Then tank and so on showing the required cut-outs (yes, I'll be beveling and rounding some edges before releasing).  I expect any deviation from a perfect separation to result in the aforementioned failure scenario.

 

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4 hours ago, NathanKell said:

@TiktaalikDreaming the traditional scaling factor is 0.64x.

 

And yes, A-10 is very, very daft. :D

0.64x?  OK.  I've gone with 0.703x on the Redstone so far to get a 1.25m rocket, but .64x would be pretty close.  Close enough to not look totally out of place.  I can pretty easily convert seeing as most of my blender models are full scale and then I rescale later.

Thoughts in order: 

This will give me more headroom in the Defender.

A-4/V-2 will get a teeny bit bigger, Redstone a teeny bit smaller

That Jeb damned Nexus ain't gonna fit in the hangers.

 

Oh, and on daft separations:  I ran a quick test using a stock decoupler staged with the A-4 engine.  And it actually worked first go.

Edited by TiktaalikDreaming

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Early test run of the A-10 without the fairing type thing.  Got a clean separation, but as expected, the large wings without control surfaces makes it steer like a train.

OK, updating the album to have properly scaled parts.  By proper, I mean the A-10 is now the same scale as the A-4, and both are 0.64 as @NathanKell suggested.

And, with parts rescaled, it no longer flies like it's on rails!  It flies like it wants to go backwards.  So far, I'm not sure if that's weight balance, misconfigured fins, or the lack of the aero shell type thing that should go over the transition between the A-10 and A-4/9.  So, I've done a fair few launches, and every one starts upwards, then starts spinning.  Once I managed to still be in the air when I exhausted the fuel so could do the separation, which actually worked (with the second stage pointed at the ground).  And I've also tested separation directly from the launchpad.  So, unlike my expectations, separation doesn't look to be a major issue.  Although it will be if the craft has any rotation.  I'll chuck an aero fairing of some sort on after work and see if I can't get the A-10 to fly in a straight line.

 

Edited by TiktaalikDreaming

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And it seems the absurd aero instability is from the A-9 wing, which I never released because something's wrong with it.  As an example of it's brokeness, coming back into the atmosphere from a suborbital flight, it will flip the A-9/4 backwards.  There's something horribly wrong with the part's aero.

An A-10/A-4 works "fine".  With the caveat that any rotation will cause explosions, etc etc.  And the fairing pieces currently fire directly forward, which is sub-optimal.  :-)

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