[UPDATED 18 Aug 2013] KEC Linear Aerospike Kit and other parts v1.1 + pictures

[Kerbolar]

I have released an update to this part pack.

Parts

New

LS-504 Linear Aerospike engine - Three segments with a built in adapter extension.

LS-505 Linear Aerospike engine - Five segments with a built in adapter.

Modified

LS-500 Linear Aerospike Segment.

- Increased weight (from 0.5 in v1.0 to 0.52 in v1.1).

- New model, lower tricount.

- New texture, better appearance.

Old

LS-501 Linear Aerospike adapter for size 1 (1 metre) rocket parts.

LS-502 Linear Aerospike adapter extension.

LS-503 Linear Aerospike aerodynamic end cap.

AS-250 Annular Aerospike at size 0 (0.5 metre).

AS-250A size 0, five metre tall rocket fuel tank.

AS-1000 Annular Aerospike at size 2 (2 metres).

This work is released under a Creative Commons CC BY-SA-NC 3.0 Unported license.

Get it at the SpacePort!

I've been a fan of aerospikes since the days of the X-33 and wanted to bring a more versatile set of these parts to the game than the stock toroidal aerospike. These parts will likely be revised in future with emissive textures and hopefully better models, but I think that this is a good start. I've tried to ensure that these parts are well balanced in terms of gameplay, each having their advantages and disadvantages.

I'd be interested to see what people think of the kit, and the other parts.

Finally... would anyone be interested in a set of spaceplane parts modelled after the X-33?

Edited August 18, 2013 by Kerbolar
Part pack updated.

[Gristle]

Interesting - I'll try them out this evening.

Maybe not the X-33, but the full size VentureStar would be kewl.

Edited August 12, 2013 by Gristle

[Uli_Stoiber]

Finally... would anyone be interested in a set of spaceplane parts modelled after the X-33?

Yes, definitely!

[Firov]

Nice work with the aerospikes. As for your question, while I would like to see the x-33, the Venture Star would be even better. I was disappointed when that program was scrapped, seeing it in game at least would be nice.

[Kerbolar]

Okay, I've started planning parts for the Venture Star!

[Ikkinomi]

Wow! Really powerful and low fuel consumption! Rockets have now a new look! I really like this mod! Good job dude!

[Gristle]

Couple of suggestions here. Too many parts. Combine the LS-501 and 5x LS-500 into one model. I would also create a LS-501 / LS-500 model that includes the end cap and combine the the LS-502 and an LS-501 into one model. By doing this you would be reducing ship part count, helping game performance and de-cluttering the staging tree.

Edited August 13, 2013 by Gristle

[BahamutoD]

Are they really that wide?

[Kerbolar]

Wow! Really powerful and low fuel consumption! Rockets have now a new look! I really like this mod! Good job dude!

I'm glad you like it I've tried to keep the power and Isp within reasonable limits while representing the potential advantages of aerospikes. I think the LS-500 may be heavier in the next release, though.

Couple of suggestions here. Too many parts. Combine the LS-501 and 5x LS-500 into one model. I would also create a LS-501 / LS-500 model that includes the end cap and combine the the LS-502 and an LS-501 into one model. By doing this you would be reducing ship part count, helping game performance and de-cluttering the staging tree.

I did wonder if the number of parts would be objectionable. So in the next release I'll add some of your suggestions. Thanks.

Are they really that wide?

Potentially, yes. The X-33/Venture Star engines were designed to be long and narrow like this. This this is KSP, I thought it'd be fun to be able to extend that to absurd lengths.

[djnattyd]

I was planning on making one of these myself, looks like you saved me the job Kerbolar. Good work

[Firov]

Kerbolar, I've been using the linear aerospikes on a few of my SSTO space planes, most of which are built on B9 Aerospace components. Anyway, I've got a few observations, as well as a suggestion.

First, you've done one heck of a job. The engines look great, and despite the fact that they're pretty fuel efficient, they're very heavy, so I feel that they're pretty well balanced. I certainly don't feel like I'm cheating with them. A line of them also throws out a very satisfying fireball, so nice work on the effects.

Now, there is a bit of a problem. The linear aerospike segments are very finicky to place properly. In fact, for a few of them, I had to turn on no-clip mode since it wouldn't let me place adjacent engine segments otherwise. This, of course, brought it's own series of challenges since the engine mounting points are so close to one another. The engine segments kept clipping into one another.

I don't know if there's a good solution here, but it's something to be aware of at least. Also, while the textures are pretty good, it's not difficult to see that the engine is composed of multiple segments. I think this is a result of the texture used on each engine segment. It may be possible to create a texture that blends seamlessly into the next engine segment.

Also, like I said, I've been using this primarily on SSTO spaceplanes using the B9 Aerospace S2 and S2 widebody fuselages, which are unusual in that they're not round. They're more of a chamfered octagon. This makes it a bit difficult to have a spaceplane based on those parts use these engines (or any others, really) and still look good. Take a look at the screenshot below to see what I mean.

I don't know if you use B9 Aerospace or not, but if you do, is there any chance you might consider making engine mounting plates for the S2 and S2 widebody fuselages? The B9 aerospace pack is one of the more widely used space plane parts packs, and I think your engines would be perfectly suited to the angular shapes it uses.

Anyway, great work on these engines. I'm looking forward to seeing them continue to evolve, and especially your Venture Star components.

[Lindy]

Finally... would anyone be interested in a set of spaceplane parts modelled after the X-33?

Yes please!... And BTW, nice job on the engine, I'm diggin' it.

[Kerbolar]

Kerbolar, I've been using the linear aerospikes on a few of my SSTO space planes, most of which are built on B9 Aerospace components. Anyway, I've got a few observations, as well as a suggestion.

First, you've done one heck of a job. The engines look great, and despite the fact that they're pretty fuel efficient, they're very heavy, so I feel that they're pretty well balanced. I certainly don't feel like I'm cheating with them. A line of them also throws out a very satisfying fireball, so nice work on the effects.

Thank you! I'm very glad to have this kind of feedback. Also the stuff that follows.

Now, there is a bit of a problem. The linear aerospike segments are very finicky to place properly. In fact, for a few of them, I had to turn on no-clip mode since it wouldn't let me place adjacent engine segments otherwise. This, of course, brought it's own series of challenges since the engine mounting points are so close to one another. The engine segments kept clipping into one another.

I don't know if there's a good solution here, but it's something to be aware of at least. Also, while the textures are pretty good, it's not difficult to see that the engine is composed of multiple segments. I think this is a result of the texture used on each engine segment. It may be possible to create a texture that blends seamlessly into the next engine segment.

Yeah, I've been thinking about the collision problem and I have a working solution It'll be in the next release. I've also just (a few minutes ago) remodelled and retextured the LS-500 spike to improve its appearance and polygon count. Things will only get better.

Also, like I said, I've been using this primarily on SSTO spaceplanes using the B9 Aerospace S2 and S2 widebody fuselages, which are unusual in that they're not round. They're more of a chamfered octagon. This makes it a bit difficult to have a spaceplane based on those parts use these engines (or any others, really) and still look good. Take a look at the screenshot below to see what I mean.

I don't know if you use B9 Aerospace or not, but if you do, is there any chance you might consider making engine mounting plates for the S2 and S2 widebody fuselages? The B9 aerospace pack is one of the more widely used space plane parts packs, and I think your engines would be perfectly suited to the angular shapes it uses.

I'd never used B9 before but I think I'm going to start! Once I've figured out the dimensions etc. I'll gladly improve a couple of compatability plates. It fits will with my plan for Venture Star part design, as a matter of coincidence.

Anyway, great work on these engines. I'm looking forward to seeing them continue to evolve, and especially your Venture Star components.

Again, thanks!

[Kerbolar]

Part pack updated.

Please see beginning of thread for specific information.

Updates are based on feedback and current capabilities

[Ikkinomi]

Potentially, yes. The X-33/Venture Star engines were designed to be long and narrow like this. This this is KSP, I thought it'd be fun to be able to extend that to absurd lengths.

Completely agree with that!

Anyway, thumbs up for this new update! Good job! I'm having good with these new engines!

[Gristle]

Love these engines! They have quickly become my engine of choice on just about everything I'm building. Performance is just right and I love the aesthetics.

[Gristle]

Have a small visual bug to report. The LS-505 engine packs connection nodes do not allow the LS-504 and LS-502 extensions to line up properly. This also affects the LS-503 end cap, but this isn't shown in my screen shot. The engine pack on the left is the LS-505 engine pack with an LS-502 attached, on the right is LS-501 and LS-502 showing proper alignment.

[Ratzap]

If you're going to start trying spaceplanes Kerbolar, you'll want to install FAR. Stock KSP aerodynamics is pretty bad in comparison.

To the spikes: I've had a go of them and my immediate reaction is - too heavy, way too heavy. Compare to stock parts and other mods (KW, NP, AIES etc) and you'll see. I understand you probably didn't want to release OP engines but you've gone too far the other way IMO. Lets compare the LS-505 with contemporary 1.25m engines with a rocket consisting of a mk1 pod, mk16 parachute and 2 FL-T800s on top of each other:

motor weight thrust aISP vISP kerb TWR adV vdV

LS-505 2.69 300 388 390 2.75 3812 3832

AIES C6 1.25 200 320 370 1.83 3968 4588

KW Mav 1D 2.00 350 320 355 3.00 3502 3885

KW Ves VR1 0.60 120 350 400 1.16 4927 5631

NP LF-A30 2.00 285 375 380 2.44 4104 4159

NP KX-2 1.20 195 350 370 1.78 4380 4692

Unfortunately it seems the spike doesn't have anything special at all. It only beats the maverick 1D on delta vee in atmosphere and at a lower TWR.

I tried making a 3 section engine but it overheated very quickly and the pre-made one has weird connections (or is it supposed to attach to the 5s?). The weight of a single section compares ok to the lv-909 for example or again slight heavy compared to the 50 thrust AIES engine but it's when scaling that the problem is compounded. There are simply too many lighter alternatives with similar efficiency. Especially with 1.25m smaller rockets, low weight is worth more than thrust (which is what the dV numbers show).

[Kerbolar]

Gristle: Thanks for pointing that out, definitely needs fixing!

Ratzap: I do want to try using both FAR and B9, but I'm having some trouble getting the game to load. I'll get there eventually.

Thanks for that thorough comparison, it's good data. I haven't used most of those engines. I do want the spikes to be representative of the advantages that they theoretically offer in reality so I'll have to do something about this. I am very cautious of making things overpowered but you've made a very good case for current configurations being underpowered. Again, thank you.

P.S. I haven't found time for KSP for about a week, hence my not replying until now.

[sirkut]

Kerbolar. Just sent you a PM on how to get the B9 dimensions.

[Shadowzdestroyer]

how to download now that space port is down?

[DracovaXIV]

I have this mod saved in my KSP mod collection. If someone needs it, ask me. The AS-250 is the best part of that whole mod... Fantastic little aerospike. I wish Kerbolar would turn up again and reply to my PMs. I want to take over maintenance of this mod, maybe have someone bundle it together with theirs. Plus, I have some ideas on how to make the mod better... Wish I had some kind of developer's kit for it.

[Gristle]

YEa - I miss this mod. Models and engines were very well done.

[Donald]

how to download now that space port is down?

Wondering the same thing. Seems no one else is maintaining a linear aerospike mod either.

[tdstrange]

Wondering the same thing. Seems no one else is maintaining a linear aerospike mod either.

The QuizTech Aero pack has a mk2 linear aerospike engine, although its not updated for FAR so I dont have it installed