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1.1 Economy challenge


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So the idea is to launch a payload to LKO with as low funds/ton as possible.

There will be 3 categories:

1. Disposable lifters. No recovery

2. Recovery allowed. No airbreathers

3. Anything goes

 

Some general rules:

1. Stock only. Visual and informative mods are ok.

2. No cheat menu or other funny business.

3. You must launch from launch pad or runway.

4. You must achieve a stable orbit. Pe >70km.

5. Payload must be separated from the lifter once in orbit. Decoupler used for this can NOT be a part of the payload.

6. Payload can have 1 pod, cockpit or probe core but nothing else that contributes any thrust, fuel or control authority to your craft. Also no lifting surfaces in payload.

7. Your score is (funds you used - payload price - recovery costs in categories 2 &3)/(payload mass in tons)

8. Screenshots or video required.

 

1. DISPOSABLE LIFTERS

1. You don't get any funds from recovery.

2. You can use ANY stock parts you like.

 

2. RECOVERABLE. NO AIRBREATHING ENGINES

1. You can use any stock parts except airbreathing engines.

2.You can recover any parts of your lifter that you can for a refund.

3. If you return parts of the lifter from orbit you don't have to land on runway or launchpad for 100% refund. Just land somewhere on kerbin and you can count 100% refund. This is because (IMO) once you are in orbit it is trivial (but time consuming and boring/irritating) to land at KSC.

4. If you return parts of the lifter that are dropped while suborbital or in atmosphere you must land them somewhere in the KSC area (not necessarily on the launchpad/runway) for 100% refund (KSC must be within sight from your landing spot). This is because again precision landing is boring/irritating. But now you can't land anywhere you want since while suborbital/still in atmosphere it is not necessarily trivial to get anywhere near KSC.

 

3. ANYTHING GOES

1. You can use any stock parts.

2.You can recover any parts of your lifter that you can for a refund.

3. If you return parts of the lifter from orbit you don't have to land on runway or launchpad for 100% refund. Just land somewhere on kerbin and you can count 100% refund. This is because (IMO) once you are in orbit it is trivial (but time consuming and boring/irritating) to land at KSC.

4. If you return parts of the lifter that are dropped while suborbital or in atmosphere you must land them somewhere in the KSC area (not necessarily on the launchpad/runway) for 100% refund (KSC must be within sight from your landing spot). This is because again precision landing is boring/irritating. But now you can't land anywhere you want since while suborbital/still in atmosphere it is not necessarily trivial to get anywhere near KSC.

 

 

LEADERBOARDS:

DISPOSABLE:

1. Tseitsei89 636.17

2.  Maccollo 642.10 

3. Cunjo Carl 753.50

 

RECOVERABLE. NO AIRBREATHERS:

1.Tseitsei 312.78

2.

3.

ANYTHING GOES:

1. Tseitsei89 83.11

2.

3.

 

And here is my entry for the disposable category to start things off:

103 436 total cost

25 028 payload cost

117.15 tons payload mass

=> 669.30 funds per tonne

Flight profile:

1. Start all engines

2. Tilt a little bit towards east to start gravity turn using twin boars gimbal and click prograde hold on

3. At around 120m/s shut down twin boar

4. When SRBs burn out you should be tilted at about 40 degree mark (see screenshots).  You can activate twin boar again when SRBs are still burning if you threaten to tilt over too quickly.

5. After SRB separation just keep burning prograde and try to hold your "time to Ap" at about half of your remaining "burn time".

6. When your Ap is >70km shut down engine. At this point your Pe should already be positive or at least very close to zero if you flew well.

7. Coast to Ap and circularize.

 

 

 

 

Edited by tseitsei89
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Perhaps rather than a 100% recovery of spent funds when recovering lifters, the price of fuel should be taken into consideration as well, because no matter how efficient the launch system is or how close you land it to the KSC, you'll still have to expend fuel to get into orbit. Also, is MechJeb allowed? It adds a very low-mass part that is needed to use its functionality (also a command pod but that wouldn't be allowed as payload anyway because it has internal fuel and engines) but is otherwise purely informative and utility (there is some autopilot functionality which assists with things like gravity turning, as well as a stability assist function, but you could perhaps add a rule preventing usage of those features if you feel like it's necessary).

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Yeah, with 100% recovery I obviously meant that you get the same amount of recovery funds as you would get if you landed on runway/launchpad. So yes fuel cost must be taken into account.

 

And Mechjeb is ok for me if it is used only as an informative mod but I don't want to allow using it's autopilot features :)

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In the SSTO category the hardware cost will be zero, it will simply come down to which ship can lift the most for the least fuel mass. 

I might have a strong contender for this, it looks like a giant motor glider and flies a bit like one too.  

20160507090916_1_zpslgjbscza.jpg

I had used 1817 liquid fuel to get this ship to orbit,  with 2 crew cabins, 1108 leftover fuel, 55 oxidizer, 3 vernier engines and an inline clamp-o-tron docking connector.     Remove all that stuff and we potentially have a real fuel sipper.  The problem is, how can i carry "cargo" in a mark 1 fuselage?

Put some xenon tanks on the nose of my plane , decouple them and re-enter with a blunt nose?  cost of my nose cone and the decoupler is not recovered.   Ditto if i sling some underwing "drop tanks" of xenon or similar.   1.25m service bays are tiny, can't think of anything heavy that would fit.

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13 minutes ago, AeroGav said:

In the SSTO category the hardware cost will be zero, it will simply come down to which ship can lift the most for the least fuel mass. 

I might have a strong contender for this, it looks like a giant motor glider and flies a bit like one too.  

Yep that is what I thought.

category 3 will be spaceplane territory because of 100% recovery + airbreathers are way better than anything else. I have yet to try and build any efficient spaceplanes but I might give it a try sometime later after I get bored of category 1...

category 1 will be SRB first stages and cheap parts and simple rockets to keep costs low I think.

category 2 might be SSTO rockets or some clever 2 stage designs that can be fully recovered. Not really sure about this. Interesting to see what people come up with :)

 

Also nice ship. Looking forward to your entry :)

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I've got a nice one for the throw-away category. It's a modular design, which can be tacked on the sides of heavy payloads in varying number and sizes. The version in the pictures can dead-lift 486 tons to LKO with a bit of fuel to spare, and costs 440,241 funds, giving it a fund to ton-LKO of 905. It's a ways off from the first place, but I think it's close enough to be worth the entry! It has a couple ancillary benefits, the largest being its ability to accommodate large or otherwise unwieldy payloads, and its relatively low part count. The picture descriptions below describe how it works. I'll give a shot at upgrading it to be recoverable, which was actually the original intent for the lifter. Thanks for the challenge!

 

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Nice monstrosity you have there :D That's some heavy lifting. Added you to the leaderboard

 

Edit: Just noticed that you have some reaction wheels in your payload I don't really think it matters much in this particular case but those should be turned off because:

6. Payload can have 1 pod, cockpit or probe core but nothing else that contributes any thrust, fuel or control authority to your craft. Also no lifting surfaces in payload.

Edited by tseitsei89
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My small and quick entry to get Anything goes category started. Not that optimized yet.

My payload was 2 full ore tanks and 4 shock cone intakes. That makes 7.52t.

I had 940 LF and 660 Ox to begin with. I was left with 120 LF and 19.70 Ox when I landed.

My craft was fully reusable so only costs were fuel costs.

LF costs 0.8 funds per unit and Ox costs 0.1818 funds per unit.

So my total costs were (940-120)*0.8 + (660-19.70)*0.1818 = 772.42 funds

So 772.42funds/7.52t = 102.72 funds/ton

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21 hours ago, tseitsei89 said:

Nice monstrosity you have there :D That's some heavy lifting. Added you to the leaderboard

cockpit or probe core but nothing else that contributes any thrust, fuel or control authority to your craft. Also no lifting surfaces in payload.

   Thanks! And good call on the reaction wheels. I typically turn them off and just rely on gimbal to conserve battery, but forgot to during the challenge. Like you were saying, for this particular case the difference is negligible, and I'd totally re-run it if I didn't create a better contender just now.

    I was gunning for the first place, but wound up a bit short. Still, I gave it my all and am happy with the results! May I present, the space whale. After submitting my first design, I had a chance to think about your ratio of SRBs to TwinBoars, and realized it's a really nice one. So I made a mashup of your design rules and mine, and scaled it up by a factor of 4 because, well... more rockets!

   The resulting lifter costs 580.4k but now handily hauls 770 tons to LKO giving it a ratio of 753,50 funds per ton to LKO. It very nearly does a 820ton payload, but reliably falls 30m/s short, and the 770 is my closest easy alternative. Still, that's 21 jumbo orange tanks, so I'm beaming with delight. Also, I put a spark on the bottom just to be cute.

 

 

 

Sadly, my plan for the reusable lifter fell through. Squad patched the exploit I was going to use to return the SRBs.... That said, a sheet of Twin boars can haul up a fair chunk SSTO, so maybe I'll try that at some point. Cheers!

Edited by Cunjo Carl
Adding digits to funds/ton value to match OP's significant figures.
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Bigger and improved version:

3840 LF and 2816 Ox on the runway.

42.62t of payload.

169 LF and 147 Ox left when landed.

2x small hardpoint as decouplers so 120 funds there.

fully recoverable

==> 83.11 funds/ton

Edited by tseitsei89
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I'll start the last category also and then leave it to you guys to improve my scores ;D

 

I did a very simple SSTO rocket with mammoth for category 2. I'm interested to see which is actually better here, SSTO or 2 stage recoverable rocket.

Fully recoverable lifter so only expenses are fuel costs.

Started with 14580 LF and 17820 OX.

Landed with 11.25 LF and 13.75 OX left.

So fuel costs were 14892.18 funds

+ 600 funds for the used decoupler.

Payload was 49.53t

So my funds/tonne was 312.78

Edited by tseitsei89
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Tseitsei - I  noticed your Spaceplane is a mark 1 like mine.

I think most of these SSTO payload challenges have really strict rules about the payload being completely inert.    If we both submit mark 1 designs with external cargo pods slung underneath,  I can imagine that designers of planes with mark 2 and 3 cargo bays complaining that 

1.  the nose and tail cones of our cargo pods should not be included in the mass delivered to orbit.  In other words, the shock cones you have mounted on your ore tanks.   They are not plausibly part of the cargo itself, having no actual use in space.  If the two ore tanks were delivered inside a cargo bay or as part of a rocket stack, the shock cones would not be needed.

2.  My entry was going to consist of a size 0 space probe carried under the SSTO like a missile.  The problem is that the nose cone i put on it actually becomes dead weight in space, it would not have one if carried inside a cargo bay.  Therefore i will have to include a separator to blow it off after release.  And the cost of my nose cone and separator will count towards the "cost to orbit"

3. I presume you're using a radial decoupler, structural pylon or small hardpoint to attach the cargo to your plane.  These are single use devices and surprisingly costly - should they be added to the "cost to orbit" as well?

4.  No matter what,  those with massive cargo bays will argue that their offerings are more versatile, since size 0 and size 1 are so limited in what they can launch.  Maybe they should just have their own category?

There's lots of ways to look at the last point.  You get people saying, "but can it put an orange tank in orbit"?     OTOH,  I can't for the life of me see why you'd want to.    For an interplanetary mission, you probably want LF only for all those NERV engines.   It's also probably just easier to mine the fuel.  If you must launch it, why fly a tank as cargo and deal with the design restrictions and cargo bay mass this imposes? Why not just drain the leftover fuel out of your spaceplane to top off your depot ?

Spoiler

 

Once I'm approaching endgame levels of tech,  there's only 3 kinds of load I fly to space

1) Spaceplane with science gear and crew accomodation, to go to places with atmosphere or no atmosphere but low grav

2) Spaceplane with ISRU gear, to sit on the permanently sunny side of Minmus, Ike etc. and refuel the explorer craft.

3) Spaceplane bringing LF from low kerbin orbit to help stuff get to Minmus unrefuelled.  Honestly, i'd rather just stage off my airbreathing engines to enable an IRSU plane to go to Minmus direct, than deal with the hassle of rendez vous and docking in low orbit.

4) wingless dedicated lander for awful places like Moho (requires absolute max delta v to reach, can't bring anything beyond pod, engine and fuel) and Tylo (requires higher TWR than my spaceplanes have and due to being airless their wings are useless).   However, these tend to be as small as possible and are easily carried up by any ssto, though they are usually sent up unfuelled.

 

 

When you start comparing one SSTO with another,  the game starts to look a little unbalanced which distorts such challenges.   Oxidizer being so much cheaper per unit than LF is a case in point, which could penalize a LF only design - though i think you got me beat for payload mass fraction ! I don't know if NERV are competitive with pure Rapier if you're only going to low orbit.  Guess i need to hurry up and submit an entry so we can look at that.

The other thing is the crazy cost of decouplers.  They are all over the place, the stack separator costing a bomb, yet the sleek streamlined small hardpoint only setting you back 60 Kredits?   

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OK attempt one.

20160521132932_1_zps6q37wvgq.jpg

My initial plan had been to remove the crew exploration stuff from the Astrojet and put payload on instead, however  Tseitsei's performance convinced me this would in no way be competitive.

Blaming the mass of my NERV engines on the deficit, i decided to try the concept of a single NERV engine.  Initial stages of the closed cycle regime have quite high drag but later on this falls below 15kn, so the vessel won't have excessive "gravity losses" from it's poor TWR, provided we use a boost below 35km based on a small amount of oxidizer and the Rapier that we're carrying anyway.

Unfortunately this design suffers from drastic  overheating probs which the heavier Astrojet does not.  I have screenshots of the Astrojet doing mach 4.33 @ 23.7km with 74% max thermal, mach 4.82 @ 30.4km with 80% max thermal, Mach 5.18 @ 31.73km @ 90% max thermal and Mach 6.28 @ 42.8km @ 97% max thermal.    However this new design could not exceed mach 5 below 50km without the wings melting. Took 10 attempts to make orbit without blowing up and I'm not going through that again - this sucker's getting deleted.

What was really weird about the way the heat worked, was that there was a certain angle of attack below which wing temperature almost instantly went critical (2 or 3 seconds, gained 30% heat, despite speed and altitude of the craft changing hardly at all).    This critical angle was 18 degrees for most of the way up, forcing me to fly a very inefficient profile.  

The only possibilities are 

1. silent patch increased heat

2. a version of module manager from one of my mods has changed the way heat is handled

3. the strakes on the Astrojet, it's longer nose or the side sponsons are somehow shielding the wing. I'd be surprised if the physics were that sophisticated.

Other lessons learned 

1. Ft100 tank wasn't enough to overcome the high drag initial closed cycle phase.

2. then again, not being able to fly faster than mach 3.75 on Rapier without melting didn't help that.

3. nor did the crazy high angles of attack forced on me by the thermal probs.

4. i had far too much liquid fuel onboard and not enough payload. 

5. The small hardpoint i used to detach the payload remained attached to the payload after separation, oops. I won't add it to the mass of payload then.   If mounted the other way, it would stay with the launcher and be recovered, so we can take this off the cost to launch.

Enough whining - results

 

Results

Launch LF 1965

LF in payload delivered to orbit 144

LF remaining on launcher after payload separation 582

1239 LF used 100LF used to deliver 2005kg payload.

Launcher had 2000dv remaining after payload separation and the probe had 4300dv.

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1 hour ago, AeroGav said:

What was really weird about the way the heat worked, was that there was a certain angle of attack below which wing temperature almost instantly went critical (2 or 3 seconds, gained 30% heat, despite speed and altitude of the craft changing hardly at all).    This critical angle was 18 degrees for most of the way up, forcing me to fly a very inefficient profile.  

The only possibilities are

3. the strakes on the Astrojet, it's longer nose or the side sponsons are somehow shielding the wing. I'd be surprised if the physics were that sophisticated.

Other lessons learned

3. nor did the crazy high angles of attack forced on me by the thermal probs.

4. i had far too much liquid fuel onboard and not enough payload.

    I similarly found this wing wanting while dabbling at reproducing results from a challenge for an airbreather-to-subortbit, ions-to-orbit space plane. It has a very high surface area, low mass and a low max temp, so its (I suspect) skin temperature has the ability to fluctuate wildly with minor changes in conditions. I've played around with conditions between 1500-2500m/s and between 20km-30km, and found that drag seems to cool the wing, as well as changing the angle of attack. Neither radiators nor struts have much effect, seeming to confirm the effect is primarily skin temperature. This makes sense, because the conditions of this flight are very similar to those of reentry.

   If you have too much fuel anyways, you might try switching to the Big Delta Wing. It provides similar lift/cost/mass but with a much higher temperature tolerance. It doesn't look as cool though, so I'm not using it. In any case, good luck!

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15 hours ago, maccollo said:

That's a fairly difficult starting entry to beat :)
For the disposable category:

172 571 total cost

43 499 payload cost

201.015 tons payload mass

=> 642.10 funds/ton

https://www.youtube.com/watch?v=KQTmHC6NGs8

 

Nice. I'll add you to the top of the leaderboard.

8 hours ago, AeroGav said:

Tseitsei - I  noticed your Spaceplane is a mark 1 like mine.

I think most of these SSTO payload challenges have really strict rules about the payload being completely inert.    If we both submit mark 1 designs with external cargo pods slung underneath,  I can imagine that designers of planes with mark 2 and 3 cargo bays complaining that 

1.  the nose and tail cones of our cargo pods should not be included in the mass delivered to orbit.  In other words, the shock cones you have mounted on your ore tanks.   They are not plausibly part of the cargo itself, having no actual use in space.  If the two ore tanks were delivered inside a cargo bay or as part of a rocket stack, the shock cones would not be needed.

2.  My entry was going to consist of a size 0 space probe carried under the SSTO like a missile.  The problem is that the nose cone i put on it actually becomes dead weight in space, it would not have one if carried inside a cargo bay.  Therefore i will have to include a separator to blow it off after release.  And the cost of my nose cone and separator will count towards the "cost to orbit"

3. I presume you're using a radial decoupler, structural pylon or small hardpoint to attach the cargo to your plane.  These are single use devices and surprisingly costly - should they be added to the "cost to orbit" as well?

4.  No matter what,  those with massive cargo bays will argue that their offerings are more versatile, since size 0 and size 1 are so limited in what they can launch.  Maybe they should just have their own category?

There's lots of ways to look at the last point.  You get people saying, "but can it put an orange tank in orbit"?     OTOH,  I can't for the life of me see why you'd want to.    For an interplanetary mission, you probably want LF only for all those NERV engines.   It's also probably just easier to mine the fuel.  If you must launch it, why fly a tank as cargo and deal with the design restrictions and cargo bay mass this imposes? Why not just drain the leftover fuel out of your spaceplane to top off your depot ?

The other thing is the crazy cost of decouplers.  They are all over the place, the stack separator costing a bomb, yet the sleek streamlined small hardpoint only setting you back 60 Kredits?   

1. You can shape the payload whatever you like as long as it doesn't add any thrust or control authority or fuel (you can have fuel as your payload but you can't use any fuel from the tanks that are part of your payload) to your craft. This is really not meant to be a challenge for practical multipurpose lifter designs but rather to find out the extreme limits of the game.

2. See point one. I would allow them as a part of payload.

3. That is a valid point. I have to test if you get refunds from used decouplers/smallhardpoint/pylons if you recover them from runway/launchpad once I get to my own computer. Or someone can tell me the answer. If you get refunds then they won't be considered as costs but if you don't they obviously arent costs.

4. They can argue. Again see point 1. Versatility is definitely useful in many other places but not in this particular challenge. The optimal crafts will probably be highly specialized to do one thing and one thing only.

4 hours ago, AeroGav said:

OK attempt one.

My initial plan had been to remove the crew exploration stuff from the Astrojet and put payload on instead, however  Tseitsei's performance convinced me this would in no way be competitive.

Blaming the mass of my NERV engines on the deficit, i decided to try the concept of a single NERV engine.  Initial stages of the closed cycle regime have quite high drag but later on this falls below 15kn, so the vessel won't have excessive "gravity losses" from it's poor TWR, provided we use a boost below 35km based on a small amount of oxidizer and the Rapier that we're carrying anyway.

Unfortunately this design suffers from drastic  overheating probs which the heavier Astrojet does not.  I have screenshots of the Astrojet doing mach 4.33 @ 23.7km with 74% max thermal, mach 4.82 @ 30.4km with 80% max thermal, Mach 5.18 @ 31.73km @ 90% max thermal and Mach 6.28 @ 42.8km @ 97% max thermal.    However this new design could not exceed mach 5 below 50km without the wings melting. Took 10 attempts to make orbit without blowing up and I'm not going through that again - this sucker's getting deleted.

What was really weird about the way the heat worked, was that there was a certain angle of attack below which wing temperature almost instantly went critical (2 or 3 seconds, gained 30% heat, despite speed and altitude of the craft changing hardly at all).    This critical angle was 18 degrees for most of the way up, forcing me to fly a very inefficient profile.  

The only possibilities are 

1. silent patch increased heat

2. a version of module manager from one of my mods has changed the way heat is handled

3. the strakes on the Astrojet, it's longer nose or the side sponsons are somehow shielding the wing. I'd be surprised if the physics were that sophisticated.

Other lessons learned 

1. Ft100 tank wasn't enough to overcome the high drag initial closed cycle phase.

2. then again, not being able to fly faster than mach 3.75 on Rapier without melting didn't help that.

3. nor did the crazy high angles of attack forced on me by the thermal probs.

4. i had far too much liquid fuel onboard and not enough payload. 

5. The small hardpoint i used to detach the payload remained attached to the payload after separation, oops. I won't add it to the mass of payload then.   If mounted the other way, it would stay with the launcher and be recovered, so we can take this off the cost to launch.

Enough whining - results

 

Results

Launch LF 1965

LF in payload delivered to orbit 144

LF remaining on launcher after payload separation 582

1239 LF used 100LF used to deliver 2005kg payload. CLARIFICATION NEEDED HERE. DO YOU MEAN 1239LF AND 100OX USED? 

Launcher had 2000dv remaining after payload separation and the probe had 4300dv.

Nice craft :) But 2 points:

1. See bolded part above

2. More screenshots (ascent, reentry and safe landing) would be nice. Not that I doubt you are cheating.... That's just a common habit for forum comps

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11 minutes ago, tseitsei89 said:

 

Nice craft :) But 2 points:

1. See bolded part above

2. More screenshots (ascent, reentry and safe landing) would be nice. Not that I doubt you are cheating.... That's just a common habit for forum comps

100 OX sorry.   I didn't get many good pictures because a) my hands were very full trying to fly the thing b) it was dark.  I'm not really counting that as an attempt tbh.This is mark 2,  The shuttle wings only hold half as much fuel and generate just over half the lift, which is why i went for the big ones - don't need as many draggy fuel ducts. 

Spoiler


20160521181130_1_zpsbmjm5oxz.jpg


 

Nevertheless it appears to have very low drag, which looks promising.

Quote

 

1. You can shape the payload whatever you like as long as it doesn't add any thrust or control authority or fuel (you can have fuel as your payload but you can't use any fuel from the tanks that are part of your payload) to your craft. This is really not meant to be a challenge for practical multipurpose lifter designs but rather to find out the extreme limits of the game.

2. See point one. I would allow them as a part of payload.


 

Hmm, fuel itself is payload?   So, I can fly to space with a load of empty mark 0 fuselage fuel tanks strapped on the pylon, with aerodynamic nose cones front and back, then in orbit transfer my remaining internal fuel into these and detach the payload.   Fuel delivery for you, bring a can opener.  Or are you going to allow dedicated tanker craft, that score points for simply having as much leftover fuel as possible to potentially offload once they reach orbit? My original Astrojet Citation reaches orbit with a lot of spare LF, it also has an inline clamp-o-tron that could be used to refuel another vessel.   Strip out the 2 crew cabins and just put some more fuel storage on it.

 

Finally I'd like to ask about the "no autopilot" rule.

As far as i am aware , it can't be used to automate spaceplane ascent, but i use it in SRF mode to command AoA changes with single degree accuracy.  Hand flying with a keyboard you're not going to be so precise so you're going to have to fly over and over and over again to get two results the same.  I'm probably just a little jaded from having wasted hours on the failed craft though.

I do think that if Mechjeb were allowed for the "maximum efficiency" launch, the same craft, unmodified but maybe slightly lower payload, should demonstrate the ability to be hand flown to orbit and back down to a safe landing without requiring superhuman flying skills. All submissions should be stable, safe and easy to fly.

spoiler - this is my Astrojet taking off with mechjeb.  you can see how i control pitch for max aerodynamic efficiency at a low workload for me.

Spoiler

 

However, you can see from these two manual landings that it also has very forgiving handling and does not NEED mechjeb.

Also, Mechjeb has problems controlling the prototype pictured in this post.  I've only recently discovered this mod but i wonder if your aircraft still needs good basic handling for Mechjeb to be able to fly it with accuracy.

 


 

 

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Well,  I haven't done the math yet to know if it's any good but mk 2 probe launcher is much nicer to fly and it looks like a 5th gen fighter from a lot of angles.   Turns on a dime too.  Pity I have no practical use for it :-(

 

20160521203826_1_zpsoegpgq8p.jpg

Although our Apoapsis is below 70km, we can shut down.  Gained another 5km off our wings before setting the AP to prograde a  minute or so later.

Full album on this link 

http://s1144.photobucket.com/user/narostel/slideshow/Astrojet%20Saphire

More highlights -

Spoiler

 

20160521205405_1_zpsbrm2skx5.jpg

Payload separation -  9 size 0 tanks with 50 fuel in each. We still have 374 fuel on the launcher itself, but if i make the size 0 tank any longer i'm concerned it's going to start flexing and cause yaw instability.  Will have to run 2 lines of 8 tanks on the top of each wing, if i can be bothered to try this again.   Right now i'd like to work on my shuttle replica :cool:

After transferring that residual liquid fuel into the fuselage tanks, which the NERV can access,  Kerbal engineer correctly calculates our delta V - 1372 m/s !

20160521212831_1_zps5oivgpj1.jpg

I started the deorbit burn to 40km  270 degrees away from KSC, just wanting to put down anywhere.  It skimmed off the atmosphere all the way round the dark side and ended up back at KSC anyway. We have rather too much height, so i fly away from the space centre towards the mountains..

20160521213641_1_zpsspzc6bpp.jpg

....and then it flies all the way down the runway and i have to do a 180 and try landing in the reverse direction..

20160521213715_1_zpspfbjjfld.jpg

Lift drag ratio of 13.259 with the landing gear out , no wonder i can't get on the runway.

20160521213818_1_zpst7kvrj1t.jpg

 

.

 

.

OK now for the math -

1765LF on Takeoff

450LF delivered to orbit

366LF landed with

Used 949LF and 100OX to bring payload weighing 2495kg to orbit.

Could obviously do better if i wasn't lifting 366 LF (weighs 1.8 tons!) all the way to orbit, just to bring it home again.

Oh BTW I used every trick in the book on this design, some dubious.    The Rapier and NERV are clipped inside each other so i can benefit from

1. both engines able to fire at once

2. only one mk1 fuselage worth of frontal area

3. symmetrical, centre of axis thrust despite having two dissimilar engines

To cap it all,  I then clipped a nose cone to the rear attach node and offset that to reduce the drag from the exhaust nozzle.

I removed the fuel ducts and forced myself to man up and transfer fuel/lock tanks. I do wonder if some wing/control surface parts are better than others though, this plane is incredibly low drag.

Edited by AeroGav
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5 hours ago, AeroGav said:

 

First of all I found out that you can't get a refund from used decouplers and such so those must be added to your costs even in reusable categories. So I recalculated my earlier reusable entries score and got 83.11 funds per ton for the plane and 312.78 for the rocket SSTO

Quote

Hmm, fuel itself is payload?   So, I can fly to space with a load of empty mark 0 fuselage fuel tanks strapped on the pylon, with aerodynamic nose cones front and back, then in orbit transfer my remaining internal fuel into these and detach the payload.   Fuel delivery for you, bring a can opener.  Or are you going to allow dedicated tanker craft, that score points for simply having as much leftover fuel as possible to potentially offload once they reach orbit? My original Astrojet Citation reaches orbit with a lot of spare LF, it also has an inline clamp-o-tron that could be used to refuel another vessel.   Strip out the 2 crew cabins and just put some more fuel storage on it.

No. The mass of the payload must remain constant during the whole flight. So you can use fuel tanks as your payload if you want but you can not use any fuel nor pump the fuel in or out of those tank.

Quote

Finally I'd like to ask about the "no autopilot" rule.

As far as i am aware , it can't be used to automate spaceplane ascent, but i use it in SRF mode to command AoA changes with single degree accuracy.  Hand flying with a keyboard you're not going to be so precise so you're going to have to fly over and over and over again to get two results the same.  I'm probably just a little jaded from having wasted hours on the failed craft though.

I do think that if Mechjeb were allowed for the "maximum efficiency" launch, the same craft, unmodified but maybe slightly lower payload, should demonstrate the ability to be hand flown to orbit and back down to a safe landing without requiring superhuman flying skills. All submissions should be stable, safe and easy to fly.

spoiler - this is my Astrojet taking off with mechjeb.  you can see how i control pitch for max aerodynamic efficiency at a low workload for me.

  Reveal hidden contents

 

However, you can see from these two manual landings that it also has very forgiving handling and does not NEED mechjeb.

Also, Mechjeb has problems controlling the prototype pictured in this post.  I've only recently discovered this mod but i wonder if your aircraft still needs good basic handling for Mechjeb to be able to fly it with accuracy.

 

 

 

 

 

 

I would really like to keep it as stock as possible... So I don't like the idea of autopilot (or any other mods). Also I don't think all entries need to be safe and easy to fly. Just possible to fly without mods...

3 hours ago, AeroGav said:

Well,  I haven't done the math yet to know if it's any good but mk 2 probe launcher is much nicer to fly and it looks like a 5th gen fighter from a lot of angles.   Turns on a dime too.  Pity I have no practical use for it :-(

 

 

Although our Apoapsis is below 70km, we can shut down.  Gained another 5km off our wings before setting the AP to prograde a  minute or so later.

Full album on this link 

http://s1144.photobucket.com/user/narostel/slideshow/Astrojet%20Saphire

More highlights -

  Reveal hidden contents

 

20160521205405_1_zpsbrm2skx5.jpg

Payload separation -  9 size 0 tanks with 50 fuel in each. We still have 374 fuel on the launcher itself, but if i make the size 0 tank any longer i'm concerned it's going to start flexing and cause yaw instability.  Will have to run 2 lines of 8 tanks on the top of each wing, if i can be bothered to try this again.   Right now i'd like to work on my shuttle replica :cool:

After transferring that residual liquid fuel into the fuselage tanks, which the NERV can access,  Kerbal engineer correctly calculates our delta V - 1372 m/s !

20160521212831_1_zps5oivgpj1.jpg

I started the deorbit burn to 40km  270 degrees away from KSC, just wanting to put down anywhere.  It skimmed off the atmosphere all the way round the dark side and ended up back at KSC anyway. We have rather too much height, so i fly away from the space centre towards the mountains..

20160521213641_1_zpsspzc6bpp.jpg

....and then it flies all the way down the runway and i have to do a 180 and try landing in the reverse direction..

20160521213715_1_zpspfbjjfld.jpg

Lift drag ratio of 13.259 with the landing gear out , no wonder i can't get on the runway.

20160521213818_1_zpst7kvrj1t.jpg

 

.

 

.

OK now for the math -

1765LF on Takeoff

450LF delivered to orbit

366LF landed with

Used 949LF and 100OX to bring payload weighing 2495kg to orbit.

Could obviously do better if i wasn't lifting 366 LF (weighs 1.8 tons!) all the way to orbit, just to bring it home again.

Oh BTW I used every trick in the book on this design, some dubious.    The Rapier and NERV are clipped inside each other so i can benefit from

1. both engines able to fire at once

2. only one mk1 fuselage worth of frontal area

3. symmetrical, centre of axis thrust despite having two dissimilar engines

To cap it all,  I then clipped a nose cone to the rear attach node and offset that to reduce the drag from the exhaust nozzle.

I removed the fuel ducts and forced myself to man up and transfer fuel/lock tanks. I do wonder if some wing/control surface parts are better than others though, this plane is incredibly low drag.

Ok sorry but I'll have to say no to clipping since that is (IMHO) very stupid concept. I mean obviously you can't put 2 or more object in the same place at the same time...

You can reduce drag too easily because you can add more engines without more drag and you can cram your payload to much much smaller package.

 

But I really like the look of your ship :D

I however calculated your score. From your numbers I get:

949 units LF used = 949*0.8 funds = 759.20 funds

100 units OX used = 100*0.1818 = 18.18 funds

1x small hardpoint used = 60.00 funds

total = 837.38 funds

payload = 2.495t

funds per ton = 837.38funds / 2.495t = 335.62 funds/t

 

I trust you can still improve that hopefully without excessive use of clipping :)

Edited by tseitsei89
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On 5/21/2016 at 2:23 PM, AeroGav said:

Well,  I haven't done the math yet to know if it's any good but mk 2 probe launcher is much nicer to fly and it looks like a 5th gen fighter from a lot of angles.   Turns on a dime too.  Pity I have no practical use for it :-(

  Reveal hidden contents

 

20160521205405_1_zpsbrm2skx5.jpg

Payload separation -  9 size 0 tanks with 50 fuel in each. We still have 374 fuel on the launcher itself, but if i make the size 0 tank any longer i'm concerned it's going to start flexing and cause yaw instability.  Will have to run 2 lines of 8 tanks on the top of each wing, if i can be bothered to try this again.   Right now i'd like to work on my shuttle replica :cool:

After transferring that residual liquid fuel into the fuselage tanks, which the NERV can access,  Kerbal engineer correctly calculates our delta V - 1372 m/s !

20160521212831_1_zps5oivgpj1.jpg

I started the deorbit burn to 40km  270 degrees away from KSC, just wanting to put down anywhere.  It skimmed off the atmosphere all the way round the dark side and ended up back at KSC anyway. We have rather too much height, so i fly away from the space centre towards the mountains..

20160521213641_1_zpsspzc6bpp.jpg

....and then it flies all the way down the runway and i have to do a 180 and try landing in the reverse direction..

20160521213715_1_zpspfbjjfld.jpg

Lift drag ratio of 13.259 with the landing gear out , no wonder i can't get on the runway.

20160521213818_1_zpst7kvrj1t.jpg

 

.

 

I removed the fuel ducts and forced myself to man up and transfer fuel/lock tanks. I do wonder if some wing/control surface parts are better than others though, this plane is incredibly low drag.

@AeroGav Hey, I think I there's a great practical use for your plane! I just kicked off the Escape Velocity: The Hypersonic Race  challenge, and the next step is to design a low parasitic drag, high L/D plane that doesn't mind going fast. Your plane totally fits the bill! I actually read through a number of your hypersonic FAR informational posts trying to make my own design, and it seems like you've made several ships that would work, but the insanely high L/D of this one is totally what's needed. Because the challenge is a 20 minute race and faster than Rapier's mach 6 limit, Nerv's the engine of choice. The only tricky part is managing the heat at the nose, for which I'd recommend an inflatable heat shield for mk.1 or 2 designs or a shuttle command pod (blegh) for mk.3. Putting big panel radiators on the inside and linking them to wings/noses with struts also helps a lot. Alright, in any case, have fun flying!

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12 hours ago, Cunjo Carl said:

@AeroGav Hey, I think I there's a great practical use for your plane! I just kicked off the Escape Velocity: The Hypersonic Race  challenge, and the next step is to design a low parasitic drag, high L/D plane that doesn't mind going fast. Your plane totally fits the bill! I actually read through a number of your hypersonic FAR informational posts trying to make my own design, and it seems like you've made several ships that would work, but the insanely high L/D of this one is totally what's needed. Because the challenge is a 20 minute race and faster than Rapier's mach 6 limit, Nerv's the engine of choice. The only tricky part is managing the heat at the nose, for which I'd recommend an inflatable heat shield for mk.1 or 2 designs or a shuttle command pod (blegh) for mk.3. Putting big panel radiators on the inside and linking them to wings/noses with struts also helps a lot. Alright, in any case, have fun flying!

Stock Aero planes don't do well in FAR, I fear the performance won't be anything like as good ! I'm planning to release this on KerbalX as a 1 man SSTO once I've finished tweaking - need to check how well it handles re-entry with cockpit, how well it can land on duna (vernier lift engines,  stronger gear?) and if a return journey from Duna is possible with the thing.

 

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Here's my entry. Just a totally stock, no clipping, no non-sense design. Delivers 73.6t to orbit with fuel left over for dr-orbit and landing.

Total fuel cost = $9,900 (actually had a bit left over so not quite this much)
Total Payload to LKO = 73.6t
9,900 / 73.6 = 134.51 funds per ton delivered to orbit

Not the best possible score, but pretty good for a stock, conventional lifter.

 

 

 

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