Economy Challenge - Cargo Delivery to LKO (1.2)

[WanderingKid]

18 hours ago, Abastro said:

That sounds great, I want to look at how it goes!

You are going to make orbit before the first stage goes under 25km, right?

Besides, I think RAPIER has so low TWR that it won't lift enough payload. For 2t is too much..

So far?  Errr, no.  Junos go to 8k, and you can eek Panthers up to 15 but realistically they die off ~11k.  It's becoming more of a hybrid SSTO (actual, not spaceplane) rocket.  I'm still having fun dinking around with it, but I'm thinking I may need to convert final stage to a spark + 1 or 2 Oscars and let it fly while doing a boostback style launcher if I want a TSTO.  I'm not that great with boostbacks, either, so this should be curious.

Edit: It's official, what I'm trying to do will simply fail as a boostback.  This will end up being either an SSTO or a Spaceplane.  I keep losing the payload during it's second stage while trying to bring the booster down.

 

18 hours ago, PrathamK said:

And how to record Videos in KSP?? I know Screenshots, Plz tell so i can Show Off here and my Friends too.

There is no native recording in KSP.  I personally use Bandicam.  A lot of others will use Fraps.  Windows 10 has a native recorder too, if I remember right, but I've never used that.

Edit 2: Screw Junos.  No, really.  Just... no.  "Thou shalt not pass!" levels of NOPE.

Edited April 22, 2017 by WanderingKid
Ranting a bit.

[Reusables]

11 hours ago, PrathamK said:

The craft works well even with poor handling but i use Mechjeb and StageRecovery. Its my Carrer mode, i want a New module of my Station to be launched. But i didn't understand how StageRecovery works, All my stage recovers autonomously and Mod is just for recovery %. What to do? 

It makes reusable TSTO trivial to make, which I don't like. Prohibiting recovery mods gives certain challenges on recoverable TSTO and makes rocket SSTO quite competitive.

10 hours ago, WanderingKid said:

It's becoming more of a hybrid SSTO (actual, not spaceplane) rocket.

Yeah I meant exactly that. If the second stage circularizes quite fast, you can taxi the first stage back to the launchpad. Boostback might be possible as well if the second stage has good TWR.

10 hours ago, WanderingKid said:

Edit 2: Screw Junos.  No, really.  Just... no.  "Thou shalt not pass!" levels of NOPE.

Oh, were they too heavy for their thrust?

[WanderingKid]

43 minutes ago, Abastro said:

Yeah I meant exactly that. If the second stage circularizes quite fast, you can taxi the first stage back to the launchpad. Boostback might be possible as well if the second stage has good TWR.

(RE: Junos) Oh, were they too heavy for their thrust?

Junos won't go high enough for a boostback, the payload can't go high enough up for the weight cost for the second stage nor are you high enough to let it 'float' a bit while you deal with the payload component.

And the less I say about those two hours wasted on space planes with an AE-FF1 cargo bay, the better.  By the time I was done with fuel costs (and needing yet MOAR BOOSTER!), I'm pretty sure it was going to cost me more in fuel for the Spaceplane than just letting it rip with the disposable launcher.

I'm dinking around with a landable SSTO deployment system I have nicknamed Stubby for the moment.  If I can get it to land without dying, it might beat out your costs for re-usable rockets.  TWR on the pad and incredibly aggressive grav turns seems to be king for low dV/weight launches.

Edit: Got it. Drone Chutes and S-turns to the rescue.  Wow this comes in hot.

1.77t for 746.89/ton.  Doesn't count until I prove it though, so just an edit.  I think this will need a video for believability, so that'll take a bit as I've got plans this weekend and it's bedtime for Bonzo.   At least I go to sleep with something fun to smile over.

Edited April 22, 2017 by WanderingKid

[PrathamK]

Can you just ignore StageRecovey, as Rockets are Expandable even, thought they are Fully Reusable (not 100% but gets, 80% back reducing 50,000 [ Why,so high, its launcher, fuel and Station Modules], including Payload, to 20,000, Including Payload)

https://m.imgur.com/x9tVWuX [ The Lander used in First Manned Mün landing]  https://m.imgur.com/axndD9C [First Mün Station, Mün Lab-1]

Both were launched by my Reusable (for you, Expandable) Launcher. 

<Cant post IMGUR photos from Link>

Edited April 22, 2017 by PrathamK

[Reusables]

9 hours ago, WanderingKid said:

Junos won't go high enough for a boostback, the payload can't go high enough up for the weight cost for the second stage nor are you high enough to let it 'float' a bit while you deal with the payload component.

And the less I say about those two hours wasted on space planes with an AE-FF1 cargo bay, the better.  By the time I was done with fuel costs (and needing yet MOAR BOOSTER!), I'm pretty sure it was going to cost me more in fuel for the Spaceplane than just letting it rip with the disposable launcher.

I'm dinking around with a landable SSTO deployment system I have nicknamed Stubby for the moment.  If I can get it to land without dying, it might beat out your costs for re-usable rockets.  TWR on the pad and incredibly aggressive grav turns seems to be king for low dV/weight launches.

Edit: Got it. Drone Chutes and S-turns to the rescue.  Wow this comes in hot.

1.77t for 746.89/ton.  Doesn't count until I prove it though, so just an edit.  I think this will need a video for believability, so that'll take a bit as I've got plans this weekend and it's bedtime for Bonzo.   At least I go to sleep with something fun to smile over.

Right.. Juno could be . And wow, 1.77t in 1322? I'm looking forward to it!

3 hours ago, PrathamK said:

Can you just ignore StageRecovey, as Rockets are Expandable even, thought they are Fully Reusable (not 100% but gets, 80% back reducing 50,000 [ Why,so high, its launcher, fuel and Station Modules], including Payload, to 20,000, Including Payload)

https://m.imgur.com/x9tVWuX [ The Lander used in First Manned Mün landing]  https://m.imgur.com/axndD9C [First Mün Station, Mün Lab-1]

Both were launched by my Reusable (for you, Expandable) Launcher. 

<Cant post IMGUR photos from Link>

Well, you need screenshots/videos for lifting payload to LKO. Were you talking about the mun lander?

Besides, I can make a category for StageRecovery if you want.

[PrathamK]

On 4/22/2017 at 8:21 PM, Abastro said:

Well, you need screenshots/videos for lifting payload to LKO. Were you talking about the mun lander?

Besides, I can make a category for StageRecovery if you want.

Well, You may didn't notice. I'm Sending the sreens tomorrow. 1 Mission has not been completed.

Well, this is my Payload (LES was jettisoned while core stage was circularizing at AP), Its not Inserting in Orbit, but Buring for Mün Transfer.

Edited April 23, 2017 by PrathamK

[WanderingKid]

So Stubby works even with a rough launch.

Stubby is a nice little wuvable wocket who just wants to visit space... and after recovery merely costs 1,437 funds (for the lost fairing and the fuel) after delivering 1.77t to orbit... for 811 funds/ton.  The fairing costs 115 funds and the fuel 1,322.

 

[Reusables]

1 hour ago, WanderingKid said:

So Stubby works even with a rough launch.

Stubby is a nice little wuvable wocket who just wants to visit space... and after recovery merely costs 1,437 funds (for the lost fairing and the fuel) after delivering 1.77t to orbit... for 811 funds/ton.  The fairing costs 115 funds and the fuel 1,322.

(snip)

Wow, Skipper SSTO for lifting under 2t, in 811/t? This is far from my expectation, as I had similar one(skipper ssto) which was quite expensive.

I'm going to try light lifters! (2t first, since I can't think of a way to lift something lighter than that)

[WanderingKid]

28 minutes ago, Abastro said:

Wow, Skipper SSTO for lifting under 2t, in 811/t? This is far from my expectation, as I had similar one(skipper ssto) which was quite expensive.

I'm going to try light lifters! (2t first, since I can't think of a way to lift something lighter than that)

It's all in TWR.  The more fuel you strip, the faster you can get away from the pad, the less you have to spend.  "It takes fuel to lift fuel" is a philosophy I'm heavily applying these cheap and light lifters.  I'm getting closer to a 3,000 dV on the pad lifter.  I might not actually get it, but we'll see.   Considering I got to orbit with ~100 dV to spare for landing with 3,193, I think it's doable.

[Reusables]

Thanks! I got my reusable lifter working with higher TWR. I can't get LKO with 3.2km/s, but there was certain improvement:

According to scoring in this challenge, this costs 290.94/t with 140.1t payload.

[OHara]

15 hours ago, Abastro said:

this costs 290.94/t with 140.1t payload.

Nice.  It is not easy to beat the results of the challenges from version 1.1.x

If you don't mind switching between craft in the atmosphere to recover the first stage, 
and if you intended to allow vertical take-off jets in category 2,
you might do really well with jets in the first stage.  

I started playing a bit with this in a single-stage lifter, because I didn't think it would be feasible to recover the jet stage if I separate it at 30km altitude.
 

Spoiler

 

Edited April 28, 2017 by OHara

[Reusables]

@OHara, indeed! I forgot that there were airbreathing engines.

As they have great fuel economy, they actually fit well in reusable lifter as the first stage engine!

For instance, I got 344.5/t from this lifter:

(Didn't take screenshots of its flight, so this doesn't count as entry)

I got the second stage from my previous lifter. 400kg of liquid fuel was enough for the first stage!

The problem is engine cost; The two engine consists 88/t of loss. (I got recovery rate of 95.6%)

Still, there are rooms of improvements; 75/t comes from other facilities aside from air intakes. Better design will reduce the cost.

Also if there's a way to handle the asymmetric flameout just after launch, I can get rid of the two small intakes.

[WanderingKid]

On ‎4‎/‎27‎/‎2017 at 7:54 AM, Abastro said:

Thanks! I got my reusable lifter working with higher TWR. I can't get LKO with 3.2km/s, but there was certain improvement:

According to scoring in this challenge, this costs 290.94/t with 140.1t payload.

That's awesome.  Might I ask at what altitude you do your first separation?

I also noticed a few things though that might help you.

When you separate the first and second stages, once the second stage gets to desired apoapsis, kill SAS and let it glide with minimal drag.  However, because it's 'on rails', that may be a moot concern.  It's something I do for my ultra high TWR lifters though during the glide from 35 - 75k.

Next up would be to play with your parachute settings with how draggy those boars are.  0.6 altitude deployment and 700m full deployment should be plenty for them.  Also, if you put them on with radial attachment you can increase the spread angle to 10 which will give you an even slower final decent.  All of that's simply to let you have a little more breathing room for switching to stage two again, as you know your landing location before hand... the water.

9 hours ago, Abastro said:

I got the second stage from my previous lifter. 400kg of liquid fuel was enough for the first stage!

The problem is engine cost; The two engine consists 88/t of loss. (I got recovery rate of 95.6%)

Still, there are rooms of improvements; 75/t comes from other facilities aside from air intakes. Better design will reduce the cost.

Also if there's a way to handle the asymmetric flameout just after launch, I can get rid of the two small intakes.

There's a long flow of thought and testing information below.  TL;DR: You're starving the Panthers and you really want to use Whiplash instead so you can hold above 25km while working with the second stage.  Use an intake with a larger surface area and a much higher effective base speed to counter the takeoff starvation before lifting, which is either the Engine Pre-Cooler or the Engine Nacelle.  The Nacelle is what you want for price as without fuel it's even lighter than the Pre-Cooler and you can probably just strip out the Mark 1 Fuel tanks.  After seeing your attempt I realized why mine were just never going to survive TSTO style builds with Panthers.

---------------------------------------------------------------

You shouldn't be getting Asymmetric burnout in 1.2.2.  At all.  I've got a 4 Panther lifter I'm playing with as an orbital fuel delivery system that has perfect burnout due to altitude with 3 intakes and a very lazy attachment process... and... oh, wait.  Are you using the Juno tiny intakes for feeding panthers? XD  I've never tried it.  However, I've ran into equivalent issues where my kNs stop going up due to starvation when you aren't moving at all, which is worth inspecting.

If you're being forced to take off wet, which is my guess for those Panthers, you might want to look into switching to Whiplash, though those are air hogs (actually, wet panthers and Whiplash are roughly equivalent), and would most likely need to use Engine Nacelles for takeoff (effective air speed 40 m/s).  The Whiplash cost 250 m/s more, but should travel a LOT higher (reducing stage two and leaving more time for recovery) as well as let you get some pretty high TWR boostback for a higher recovery value. 

During some simple testing I found that Whiplash + Nacelle ran ~119.8 kN on the pad without starving.  It goes up to 290+ kN through Mach 2.6 while lifting, but you need to lift, so that's just bonus during flight for extra apoapsis during its 'speed run'. Dropped to under 120kN at ~18k, and it cut out completely on me at ~ 27km up during a straight up shot.   The Pre-Cooler lets you squeak out a little bit more but for a straight up launch you're not going to see a significant benefit for long enough.

Compare to the Panther: Dry 75.1 kN on pad.  Wet: 125.6k kN on pad.  Also steadies out at ~120 kN.  However, it starts falling hard at 11k to negligible amounts by 15k and cuts out completely at ~21kM during a straight up. 

If those ARE Whiplash on the bottom of the lifter, sorry about that!  At least the testing helps validate some things I was trying to figure out.

Edited April 28, 2017 by WanderingKid

[CoreI]

What category would an X37-B style launch be under? I'm working on one currently that blends the Falcon 9 (recoverable first stage) and a NERV-powered spaceplane?

In case you don't know what X37-B is: https://en.m.wikipedia.org/wiki/Boeing_X-37

Edited April 29, 2017 by CoreI
Clarified first stage reusability.

[WanderingKid]

23 minutes ago, CoreI said:

What category would an X37-B style launch be under? I'm working on one currently that blends the Falcon 9 and a NERV-powered spaceplane?

In case you don't know what X37-B is: https://en.m.wikipedia.org/wiki/Boeing_X-37

EDIT: After further reading, I need to revise my comment.  X37-B is a Type II recoverable lifter.  You're simply not bothering to recover the first stage.  Whatever the X37-B drops off in orbit, untouched, is your payload.

Edited April 28, 2017 by WanderingKid

[WanderingKid]

18 hours ago, OHara said:

Nice.  It is not easy to beat the results of the challenges from version 1.1.x

I definitely agree with that.  I'm currently trying to see what I can do with another semi-standard payload I use, a 12t fuel refueler in LKO that is 17.2 tons after all the rendezvous and control parts.  My spaceplane I limited to Tech 2 parts so it's a Panther build, and can't get anywhere near your 10t delivery, and that's sitting on the edge of near perfect ascent profiles with no room for error.  I may revisit it for fun with some rapiers and stuff at some point but I think I've pretty much gotten that bird as perfect as I can personally get it at 4,218 in fuel, for 351.5/t for 12t fuel payload.  Near miss ascents can be recovered by using a portion of the payload, but still... that's nowhere near what you were able to get with rapiers.

 

@maccollo 's entry in the disposable rocket category at 61.87/t is nigh un-achievable at under 1/3 the weight.  Fairings are seriously not helping my attempts, either, but that's a personal concern, as I'm not interested in random payloads but ones I'll actually use repeatedly for the amount of tweaking and overanalyzing I'm doing.  Even if I include the fairing in the payload cost I still can't get near it, it's not the extra 1.5k funds that's throwing me off.  I keep coming in close to 1,000 - 1,100/t for this payload when I don't do anything particularly inane.  I may have just found one of those odd tonnage rates where the skipper provides good upper atmo value but it needs a boost for liftoff with kickbacks that are too expensive for the weight, but the Thumper just doesn't have the oomph.

Edited April 29, 2017 by WanderingKid

[Reusables]

16 hours ago, WanderingKid said:

That's awesome.  Might I ask at what altitude you do your first separation?

Thanks. The separation altitude is about 16km~18km.

16 hours ago, WanderingKid said:

When you separate the first and second stages, once the second stage gets to desired apoapsis, kill SAS and let it glide with minimal drag.  However, because it's 'on rails', that may be a moot concern.  It's something I do for my ultra high TWR lifters though during the glide from 35 - 75k.

Usually I only mount OKTO probe on the first stage, so the SAS torque force is next to nothing. Though I need to turn off SAS sometimes, because electricity runs out otherwise.

16 hours ago, WanderingKid said:

Next up would be to play with your parachute settings with how draggy those boars are.  0.6 altitude deployment and 700m full deployment should be plenty for them.  Also, if you put them on with radial attachment you can increase the spread angle to 10 which will give you an even slower final decent.  All of that's simply to let you have a little more breathing room for switching to stage two again, as you know your landing location before hand... the water.

That's what I do as well.

I usually set the altitude to 250m~500m depend on lifters. Also I set the spread angle to 10 for every lifters.

16 hours ago, WanderingKid said:

There's a long flow of thought and testing information below.  TL;DR: You're starving the Panthers and you really want to use Whiplash instead so you can hold above 25km while working with the second stage.  Use an intake with a larger surface area and a much higher effective base speed to counter the takeoff starvation before lifting, which is either the Engine Pre-Cooler or the Engine Nacelle.  The Nacelle is what you want for price as without fuel it's even lighter than the Pre-Cooler and you can probably just strip out the Mark 1 Fuel tanks.  After seeing your attempt I realized why mine were just never going to survive TSTO style builds with Panthers.

I was looking for low-tech lifter, thus the Panther.

I thought whiplash is not good for the first stage booster since it works better on higher altitude. It gives nice push on supersonic region, but it's 50% heavier and a bit more expensive. Now realized that it could be better option, I should investigate it.

Besides, now I realized that Divertless Supersonic Intake was probably not the best choice. Engine Precooler is too expensive, but cheap Engine Nacelle might provide enough air as you demonstrated with a test.

16 hours ago, WanderingKid said:

You shouldn't be getting Asymmetric burnout in 1.2.2.  At all.  I've got a 4 Panther lifter I'm playing with as an orbital fuel delivery system that has perfect burnout due to altitude with 3 intakes and a very lazy attachment process... and... oh, wait.  Are you using the Juno tiny intakes for feeding panthers? XD  I've never tried it.  However, I've ran into equivalent issues where my kNs stop going up due to starvation when you aren't moving at all, which is worth inspecting.

I was using the cheap Divertless Supersonic Intake. It lacks intake air on takeoff, so I need two mk0 intakes to prevent asymmetric thrust.
  (I think the bug retains when intake air is not enough just after takeoff)

16 hours ago, WanderingKid said:

The Whiplash cost 250 m/s more, but should travel a LOT higher (reducing stage two and leaving more time for recovery) as well as let you get some pretty high TWR boostback for a higher recovery value.

I think boostback is really hard to perform with airbreathers, since you are already high up (typically over 30km) when it's needed. Then, more horizontal speed means more distance from KSC(less recovery rate).

 

Anyway, thanks for kind feedback and advice!

 

16 hours ago, CoreI said:

What category would an X37-B style launch be under? I'm working on one currently that blends the Falcon 9 (recoverable first stage) and a NERV-powered spaceplane?

Yes, this belongs to the category II (Reusable Lifter) as @WanderingKid said.

 

12 hours ago, WanderingKid said:

@maccollo 's entry in the disposable rocket category at 61.87/t is nigh un-achievable at under 1/3 the weight.

That's it! Orbiters tend to be more efficient with heavier payload.

That's why I don't bother to list light entries even if it's less efficient than those heavier ones.

[Reusables]

So I experimented with Panther and Engine Nacelle. And..

This lifter had no problem like asymmetric thrust, and lifts 2t in 656

So 328/t. Impressive!

EDIT: Tried Whiplash. At the first time I thought it won't worth it because I just didn't put enough payload on it. Now I realized it just needed more payload.

272.76/t. I don't take the screenshots of takeoff and such, so this won't count as entry as well.

Edited April 29, 2017 by Reusables

[WanderingKid]

4 hours ago, Abastro said:

So I experimented with Panther and Engine Nacelle. And..

This lifter had no problem like asymmetric thrust, and lifts 2t in 656

So 328/t. Impressive!

EDIT: Tried Whiplash. At the first time I thought it won't worth it because I just didn't put enough payload on it. Now I realized it just needed more payload.

272.76/t. I don't take the screenshots of takeoff and such, so this won't count as entry as well.

Nice work there! Absolutely shatters my 1.77t lifter cost/ton.  Looks like I'll have to revisit it! XD