[1.1] AB Launchers 1.2 - 5m Energia parts [22 Apr]

[hoojiwana]

0.2 update!

Important: Folder changes mean you must delete AB Launchers 0.1 install before updating.

Changelog:

• Added a 5m upper stage engine (Whirlwind x7)
  
• Changed folder layout, moving all three engines into one folder
  
• Increased 5m stack decoupler decoupling force
  
• Increased 5m core engine (Cyclone x4) thrust, mass, cost and entry cost
  
• Decreased 5m core engine (Cyclone x4) atmospheric ISP and vacuum ISP
  
• Increased 2.5m booster engine (Hurricane) thrust, mass and cost
  
• Decreased 2.5m booster engine (Hurricane) atmospheric ISP, vacuum ISP and entry cost
  
• Added ModuleTestSubject to the Hurricane
  
• Changed the 5m stack decoupler flavour name so it is with the other stack decouplers when using name ordering in the editor

Known issues:

• No part descriptions
  
• Agency config and flag is placeholder
  
• No smoke on either 5m engine cluster

[wasmic]

It is Hydrolox! (Or it is supposed to imitate Hydrolox)

So, not as smokey as some other types of fuel.

Actually, neither hydrolox nor kerolox are smokey at all. If anything, they're steamy.

[Tapejara]

That Whirlwind engine is quite a beast! Not sure it's strictly necessary given how powerful a single-core design already is, but it certainly looks cool.

[hoojiwana]

That Whirlwind engine is quite a beast! Not sure it's strictly necessary given how powerful a single-core design already is, but it certainly looks cool.

If it's too much it can always be toned down a little, most likely by dropping the thrust a bit. It was added since now the main engines are a bit thirstier, the big Vulkan-type designs are much less capable than they were before. It also provides a nice part for those that may want to build further vertically, or with using 3.75m/5m booster stages for even bigger payloads that may need an orbital kick. It's also a lot easier to rotate the split rocket to face a heading than a full length core stage!

[Tapejara]

If it's too much it can always be toned down a little, most likely by dropping the thrust a bit. It was added since now the main engines are a bit thirstier, the big Vulkan-type designs are much less capable than they were before. It also provides a nice part for those that may want to build further vertically, or with using 3.75m/5m booster stages for even bigger payloads that may need an orbital kick. It's also a lot easier to rotate the split rocket to face a heading than a full length core stage!

Those are all sound reasons for including the Whirlwind. I withdraw my previous criticism!

Edited February 14, 2015 by Tapejara

[Tapejara]

I tried out a Zenit launcher with the new, punchier, dirtier Hurricane:

Second stage is from the Tantares ALV, and the payload was in the region of 10-15 tonnes. It seems a reasonable launch vehicle, made it to low Kerbin orbit but didn't have the delta-V to go beyond that. I'd call that a success myself, useful but not overpowered.

[Beale]

I tried out a Zenit launcher with the new, punchier, dirtier Hurricane:

http://i.imgur.com/T1mXiJW.png?1

Second stage is from the Tantares ALV, and the payload was in the region of 10-15 tonnes. It seems a reasonable launch vehicle, made it to low Kerbin orbit but didn't have the delta-V to go beyond that. I'd call that a success myself, useful but not overpowered.

Great little thing there!

The payload capacity seems about right for a Zenit, so that's good! It was probably slightly overpowered before.

Unfortunately I've been a little lacking in free time lately, but there is also a 2.5m decoupler planned for AB launchers, as the stock colourful ones do not look so amazing against the tanks.

A Zenit upper stage engine (RD-120-Alike) is also possibly on the cards, as none of the stock engines quite fit the bill for what is required.

Edited February 17, 2015 by Beale

[Tapejara]

Great little thing there!

The payload capacity seems about right for a Zenit, so that's good! It was probably slightly overpowered before.

Unfortunately I've been a little lacking in free time lately, but there is also a 2.5m decoupler planned for AB launchers, as the stock colourful ones do not look so amazing against the tanks.

A Zenit upper stage engine (RD-120-Alike) is also possibly on the cards, as none of the stock engines quite fit the bill for what is required.

Matching decouplers and 2.5m engines would be cool, and a 5m SAS would be handy too, perhaps incorporated into the largest nosecone. For building Energia/Vulkan analogues though the pack is pretty good as it is.

Edited February 25, 2015 by Tapejara

[Sampa]

Like what I see, thus far! gj!

[tg626]

Playing with the parts in the VAB I got a look-alike Saturn V put together - sadly, while the big 5m engine got it off the ground (barely) the 7 nozzle could not boost it any further (.5 TWR I noticed when I stopped to look LOL).

Made me think, with 2 engines (a wide 5 nozzle like the F-1s, and a 4 nozzle with more thurst and a fairing) it would make a nice Saturn parts set too!

All that aside - while I can find plenty of prototype examples of the energia and it's derivatives, I can't find any thing with the 7 nozzle engine - where did that come from? Imagination or is/was there a real world prototype (or proposal)?

[Beale]

Playing with the parts in the VAB I got a look-alike Saturn V put together - sadly, while the big 5m engine got it off the ground (barely) the 7 nozzle could not boost it any further (.5 TWR I noticed when I stopped to look LOL).

Made me think, with 2 engines (a wide 5 nozzle like the F-1s, and a 4 nozzle with more thurst and a fairing) it would make a nice Saturn parts set too!

All that aside - while I can find plenty of prototype examples of the energia and it's derivatives, I can't find any thing with the 7 nozzle engine - where did that come from? Imagination or is/was there a real world prototype (or proposal)?

That's an interesting idea with the engines there!

Did you try this layout? (No idea what kind of TWR you would get from this).

The 7-Nozzle engine, I don't think it's a real concept, IIRC hoojiwan's christened it the Poodle x7, which is quite a nice concept

Edited April 3, 2015 by Beale

[tg626]

Trying to do energia with a dummy payload, typical flipping with an asymmetrical thrust/load. Seems like a powerful 5m SAS ring would be a good idea :-)

I offset the strapon boosters like it is typically shown in drawings of polyus/buran

Edited April 4, 2015 by tg626

[hoojiwana]

All that aside - while I can find plenty of prototype examples of the energia and it's derivatives, I can't find any thing with the 7 nozzle engine - where did that come from? Imagination or is/was there a real world prototype (or proposal)?

The 7x cluster is totally made up, and as Beale said it's essentially just 7 Poodles all stuck together on one part. The reason I went with that design over something more realistic (ie: a single RD-57M) was one of scale. A lone engine like that would've had a low TWR for those big upper stages (some of my tests were entire Kerbal X rockets), making gaining orbit very difficult due to Kerbins small size. In real life you can spend a long time doing a low TWR burn in upper stages but around Kerbin it's a lot less viable.

[tg626]

Well I give up - I can't seem to "get" the Energia at all... the booster offset looks like it's 100% backwards from what you'd want with an asymmetrical payload - by all appearances Polyus at least was unpowered - by which I mean it offered no thrust for ascent, I know about it's backwards mounting and it's on board thrusters for orbital insertion.

I just can't wrap my head around it. At least with the Space Shuttle, you can SEE the vectored thrust from the shuttle's engines, which of course Buran didn't have... GAH! Giving me a headache just thinking about it to write this post LOL....

[tjsnh]

While this thread isn't super active, I _LOVE_ these parts and use them constantly. Incredible work all around.

[tg626]

Still working on it... Increasing gimbal to 8 degrees helped alot. Edited April 5, 2015 by tg626

[Beale]

While this thread isn't super active, I _LOVE_ these parts and use them constantly. Incredible work all around.

Many thanks (On behalf of the 2.5m part division)!

Still working on it... Increasing gimbal to 8 degrees helped alot.

Great job there!

Interesting you could get away with 8 degrees, is it unstable?

I think the Polyus had much smaller radial fuel / engine bits? (Like 0.625 compared to the 1.25 you have there) Which could be contributing a lot more asymmetric mass than you need!

Honestly though, my largest radial payload was only in the range of ~ 9 tons, which is a hell of a lot easier than what you're working with there.

[tg626]

Great job there!

Interesting you could get away with 8 degrees, is it unstable?

I think the Polyus had much smaller radial fuel / engine bits? (Like 0.625 compared to the 1.25 you have there) Which could be contributing a lot more asymmetric mass than you need!

Honestly though, my largest radial payload was only in the range of ~ 9 tons, which is a hell of a lot easier than what you're working with there.

It starts getting unwieldy as it nears empty! LOL

My Polyus is, as most of my "copy stations" are, a fuel depot in disguise. The TKS part is made of custom LFO tanks made from your TK RCS tank, and the ALV C fuel tank, and the other half is the shortest 2.5m AB Launcher tank and the ALV B tank - it's fully loaded, so it weighs in at 90+ tons!!

I've gotten it to orbit - using MechJeb. I fly to 10K before the gravity turn, then around 40km I start using "limit throttle to XX%" to cut back on thrust - all the while watching that I don't get too close to my apoapsis. At around 60km I have about 4 mins to apoapsis, and my periapsis is nearly 0m.

I disengage MJ, decouple Polyus, switch control to an inverted LC-01, and swing it 180 degrees before re-engaging MJ to finish the ascent.

It's a very manual automated ascent!!

I also use SpaceY's 5M SAS collar on the tank now (not shown in that video). It does indeed help.

FWIW I based my 8 degrees gimbal on something I read, which was that the RD170 had a 6 degree gimbal, but was shown in tests to achieve 8-10 degrees of deviation.

At 90 tons, (86 tons in orbit last launch) those asymmetric bits are the least of my troubles!

[tg626]

Update:

Added SpaceY 5M SAS collar, and upped the large engine's gimbal to 15 degrees.

Successful Launch Video

Vid cuts off a touch early, but here it is in orbit:

That's 90 tons into a 74km x 77km orbit!

Boosters waiting for recovery:

[planeguy868]

Update:

Added SpaceY 5M SAS collar, and upped the large engine's gimbal to 15 degrees.

Successful Launch Video

Vid cuts off a touch early, but here it is in orbit:

http://i.imgur.com/X8hnO6p.png

That's 90 tons into a 74km x 77km orbit!

Boosters waiting for recovery:

http://i.imgur.com/KkTmjfk.png

What tank is the one that's furthest to the bottom of the Polyus core? I don't recognize it!

[tg626]

If you mean what I think you mean it's the blok c tank from ALV found in tantareslv.

[tg626]

BTW - to the Authors:

I think the "Cyclone" would be better as a "Thrust Plate" with four bottom nodes, and individual engines. Thinking on it, this along with greater gimballing would do a lot to help balance things during launch. Further, throttle controlled avionics could also be used if there were 4 separate engines.

[Beale]

It starts getting unwieldy as it nears empty! LOL

My Polyus is, as most of my "copy stations" are, a fuel depot in disguise. The TKS part is made of custom LFO tanks made from your TK RCS tank, and the ALV C fuel tank, and the other half is the shortest 2.5m AB Launcher tank and the ALV B tank - it's fully loaded, so it weighs in at 90+ tons!!

I've gotten it to orbit - using MechJeb. I fly to 10K before the gravity turn, then around 40km I start using "limit throttle to XX%" to cut back on thrust - all the while watching that I don't get too close to my apoapsis. At around 60km I have about 4 mins to apoapsis, and my periapsis is nearly 0m.

I disengage MJ, decouple Polyus, switch control to an inverted LC-01, and swing it 180 degrees before re-engaging MJ to finish the ascent.

It's a very manual automated ascent!!

I also use SpaceY's 5M SAS collar on the tank now (not shown in that video). It does indeed help.

FWIW I based my 8 degrees gimbal on something I read, which was that the RD170 had a 6 degree gimbal, but was shown in tests to achieve 8-10 degrees of deviation.

At 90 tons, (86 tons in orbit last launch) those asymmetric bits are the least of my troubles!

90 tons! Okay, that's a fair difference

I'm amazed you got it anywhere near orbit in that case!

If the SAS collar provides a significant benefit that could be an interesting avenue to make the Energia more "user friendly". Thanks for the info!

Anyway the station looks great! Almost like an Mercury-Atlas rocket in shape.

BTW - to the Authors:

I think the "Cyclone" would be better as a "Thrust Plate" with four bottom nodes, and individual engines. Thinking on it, this along with greater gimballing would do a lot to help balance things during launch. Further, throttle controlled avionics could also be used if there were 4 separate engines.

There are some plans for 2.5m versions of the individual Cyclone engines, for a future version of AB.

Your point about throttle controlled avionics is very true.

Note that this is a W.I.P. screenshot, and not mine. hoojiwana may offer some more details on the specifics of this engine, I can't remember the full plans for it unfortunately.

All the activity in this thread wants me to get started on a few more parts, when I have free time

[tg626]

Now I'm trying to get a Buran together... Wings are proving to be a problem

[planeguy868]

If you mean what I think you mean it's the blok c tank from ALV found in tantareslv.

No, not that one. The one that's at the bottom relative to the image, the duller gray tank with dark gray bottom section,