# Teutooni

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2. ## What is your favorite stock engine?

48-7S "Spark", Skipper being a close second. The spark used to be downright OP before 1.0, and still I find nearly all my "every gram counts" landers and probes gravitate to using it. It just hits this sweet spot of high TWR and decent ISP for it's size. Skipper because I love the model - I think it's the best looking rocket engine in the stock game.
3. ## Most Dangerous Spacecraft Fuel

Liquid fluorine or ozone oxidisers would give neat ISP, but are suicidally unstable. Afaik, even at cryogenic temperatures, pure ozone can trigger a spontaneous explosive chain reaction via normal heat fluctuations, breaking down into O2. Imagine launching that stuff on a shaking rocket.
4. ## Oberth effect

Incidentally, using just maneuver nodes, it takes exactly 951 m/s to reach Kerbin escape from 70.1 km orbit. As you can see in this picture, 950.9 m/s is still "inside the SOI", with apparent apoapsis well over Jool's orbit. I think the node system uses infinitely large SOI, i.e. real escape velocity. Doing the actual burn instead of fiddling with nodes gives numbers close to 938 m/s and 84Mm SOI radius.
5. ## Oberth effect

As I understand it, to leave Kerbin SOI, the minimum you need is the Hohmann transfer orbit to Kerbin SOI. Plugging the numbers into the transfer equation: sqrt(u/r1)(sqrt(2*r2/(r1+r2))-1), where u = G*M, r1 is initial circular orbit (670000 m) and r2 is the edge of SOI (84Ã¢â‚¬â€°159Ã¢â‚¬â€°286 m), I get 937.854 m/s. Which seems about right according to my experience. Add the orbital velocity (I was lazy and used browser calculator: http://files.arklyffe.com/orbcalc.html) of 2295.5 m/s and the burnout is 3233.4 m/s. The actual escape velocity from Kerbin, using Ve = sqrt(2*u/r), is 3245.9 m/s from 70km circular orbit. There is a difference of 12.5 m/s. Which seems to confirm what OhioBob just posted while I was writing this.
6. ## How far have you gone in Kerbal Space Program?

I once designed and built a great arkship with closed lifesupport loop for 10 kerbals (TAC-LS + USI), several landers for exploring every landable body, robotic fuel miners and refineries, etc. Iirc it was close to 400 parts with over 800 tons mass. It was designed to be able to explore everything and never need to return. You can see where this is going don't you? Just turning the thing was measured in orbits, not minutes or seconds. Needless to say it never left kerbin SOI, it was simply too painful to play. The most difficult/complicated thing I've done mission-wise is probably an unmanned duna mission with remote tech signal delay. The mission included 5 separate probes carried by one rocket: a communications hub with large antenna, an orbiter with SCANsat equipment for both duna and ike, plus landers for both. Landing with and without atmosphere become quite interesting when there's over a minute signal delay. Both are doable, but need some tricks. Piloting-wise the most difficult thing was landing a 200-ton spaceplane on Tylo with TWR of 1.2. It was fusion powered (KSPI), so insane delta-v but low TWR. Iirc a suicide burn distance would have been almost outside Tylo's SOI. It was a great educational experience - I think everyone should familiarize themselves with constant altitude landings. Literally the farthest I've been is Eeloo, but don't really consider that a significant achievement. Just pack enough lifesupport for a decade or two and it's not that different from any interplanetary trip. Still haven't returned from Eve on any version.
7. ## I have been doing some testing on Fairings, and pre-coolers

I confirmed OP's observations about precoolers - they have no real effect. Test vehicle was this (craft file). Needs tweakscale because I couldn't be arsed to make the wings out of multiple parts. First run: Whiplash with precooler replaced by empty mk1 fuel tank (mass 0.2t): speed at 17km level flight: 1430 m/s Second run: Whiplash with a precooler emptied of fuel and air intake closed (mass 0.2t): speed at 17km level: 1428 m/s Third run: RAPIER with an empty precooler with air closed: speed at 20km level 1684, can just barely make it to 1703m/s by doing a shallow dive from 21 to 20km. Fourth run: RAPIER with precooler replaced by empty fuel tank: speed at 20km level 1687 m/s, can also barely make it to 1702m/s in a shallow dive. Fifth run: RAPIER with precooler empty of fuel but air intake open: speed at 20km level 1685 m/s, can make it to 1705m/s in a shallow dive. Absolutely no difference. Intake air from precooler reads 0.0 at those speeds/altitudes. I did not use any autopilots so the tests might not be entirely valid, but I think it is safe to say the effect is negligible if there at all. Any difference in speed could easily be accounted for by small differences in pitch angle.
8. ## Poll, the R.A.P.I.E.R, what do you think it needs

Balance-wise I think it's ok. I'd actually reduce the thrust at mach 2-3 a little and maybe compensate with slightly less steep decline in performance at higher altitudes.
9. ## Teleportation big question: does it kill person in process?

Here is a thought experiment for you. Consider regular movement through quantized spacetime. If a macroscopic object such as a person moves the smallest possible distance does he die? There is no motion between the states, one time instant he is somewhere and the next he is somewhere else. What if he moves not to an adjacent 'pixel' but skips a few, does he die? If the person gets disintegrated, transferred as information and reconstructed, is that any different? Does it even matter if you are dead while in transit?
10. ## Burials Galore [How do you want to be buried]

Non fui, fui, non sum, non curo. In other words, I don't give a damn how I am buried. I suppose I will donate everything usable to medicine/science, as I see that as a sensible thing.
11. ## What is the X-37 for?

Much easier to design a unit that self-destructs upon re-entry. De-orbit and blow up a small explosive aboard, scattering anything useful to a million pieces that burn fast. They want something back, and that something is test items/data for analysis.
12. ## Conscience Experiment

"You" is a vague concept and if you can define it precisely you will have your answer. As a side note the SchrÃƒÂ¶dinger's Cat has nothing to do with consciousness. It deals with the cat's fate being decided by measuring a quantum state, and prior to the measurement the cat is effectively both dead and alive. It could be a rock, and it would be simultaneously an intact and a smashed rock if the experiment was modified to destroy a rock upon activation instead of killing a cat. Again, answering whether quantum fluctuations affect our consciousness or if "you" die when there's an exact copy somewhere is entirely dependent on what the mind precisely is and how you define "you". If you define "you" as a conscious, thinking entity then you die every night. If "you" includes subconscious mind and memories, reflexes etc. it gets messy. If you lose your memory due to illness, do "you" die? There are cases where brain injury has completely changed one's personality. What if you learn something that deeply affects you and makes you change, did the old you die? If you define "you" as a learning process that guides your body, then you die when said process stops. These are just to mention a few definitions.
13. ## Why shouldn't humanity last for billions of years?

We are not talking about sending the first ENIAC of AI, we are talking about cosmic timescales. Billions of years. A recent ted talk mentions current experts believing we'll have a human-level machine intelligence in 20-30 years. That is, as good as us in everything, including creative thinking. I am not talking about sending one massive skynet to space, I'm talking about a population of superintelligent machines. Machines that could be more "humane" than us. This is ofc very optimistic, but I see it as our best shot at surviving the challenges of spaceflight on long timescales.
14. ## Space Shuttle V2 Thought Experiment

The problem is there is no clear consensus afaik as to how metallic hydrogen behaves if it can be produced at all. It could be metastable under mild pressures, possible needing to be cryogenic. But yeah, that is probably even more far-fetched than tail-landing 100-tons-empty lifting stage needed for 60-tons payload to LEO.
15. ## What's your favourite element of the periodic table(if you have one)?

Hydrogen, obviously. Hydrogen + time => everything else. Has very nice energetic properties (fusion fuel, LH2/LOX, has a lot of interesting phases that are also very energetic). Atomic hydrogen reacts with almost any element, also forms one of the strongest chemcal bonds known with itself.
16. ## Space Shuttle V2 Thought Experiment

Considering the constraints outlined in the op, I'd say it would require some rather exotic fuels like MSMH to be able to lift heavy payloads reusably. As I understand it reusability cuts into payload fraction and would make large payloads prohibitively costly. Given STP metastable metallic hydrogen SSTOs with incredible payload fractions would be possible. 1500 second Isp with similar thrust to RP-1/LOX, yes please!
17. ## Why shouldn't humanity last for billions of years?

The way I see it, intelligent biological life is not well suited to surviving cosmic timescales. Evolution is a powerful adaptive process, life can thrive almost everywhere on earth. But we know of only one example of life leaving earth. It requires not adaptation, but prediction. Something biological evolution is incapable of. Which leaves intelligence, the predictive component. (yes evolution produced intelligence but is not itself capable of prediction and intelligence is not necessarily tied to evolution). If we can design a machine that is at least as intelligent as us, our legacy has a fair chance of surviving cosmic timescales. Machines are much better suited to space travel. No need for complex lifesupport, no need to live on planets or have artificial gravity, can be very small compared, etc. They could be a true spacefaring civilization with no need to land on planets except perhaps to mine resources or nostalgy or tourism or something. If we define them as our offspring, then we have a fair chance to survive a long time.
18. ## Do you run missions in serial or more than one at a time?

I use KCT and KAC, but havent yet run parallel missions. Just returned from a mission that did a manned landing on Ike and Duna. Was a couple hundred delta-v short on reenterinng Kerbin so planned a rescue tug for when the lander returned to Kerbin SOI. I could have done lots of tourist/satellite contracts but couldn't be arsed. Now that I have the duna science I will probably set up something reusable for tourists while I wait for the transfer to Eve to complete.
19. ## Rethinking the nuke engine, where can we take it from here?

I miss the old interstellar nukes (I believe it was last updated for .25). They were fairly complicated, had cool looking radiators, different nuclear fuels, different propellants etc. Iirc the first fission nukes had worse TWR and Isp than stock, which was and still is ridiculously easy to use. Later models especially large fusion rockets started getting huge Isp, but up to that point they were imo fairly balanced and more fun to use than stock. As to the op question, thats the direction I'd like stock to go.
20. ## Veteran players reminisce: What was your first Munar landing like?

Back in 2012, can't remember which version. I guess it was pretty typical: 1st attempt: too aggressive on the lithobraking. 100m/s too agressive. Splat. 2nd attempt: way too careful, managed to land but wasted all the fuel meant for return. Technically a successful landing. 3rd attempt: managed to touch down but was a bit rushed and sloppy, rocket fell over. 4th attempt: wider lander with lower CoM, landed with enough fuel for return.
21. ## Am I the only one who sees Jebediah and Valentina as rivals rather than a pair?

Never gave it much thought, but as Val is the newcomer and just as badass as Jeb she strikes me as Jeb's niece or something.
22. ## what is ur favorite moon

Laythe - beautiful ocean moon with a breathable atmosphere, what's not to like?
23. ## You know you overbuilt your rocket when...

When you take your spaceplane for a stability test flight, reach orbit, see that you can reach Minmus and land there. Then you notice you still have 36 tons of fuel as payload, unlock it and do a flyby of Laythe.
24. ## What's the Most Science/XP You Gained in One Mission? (Spoilers)

Haha true words. Trips to Jool are always so much fun. It's easy to encounter and there are always many interesting opportunities to encounter with 5 moons in the system. My most science in 1.0 is just ~500 with a munar landing on the border of 2 biomes, although I am planning to do a full Duna+Ike exploration mission that should be around 5k science. My most science ever was a heavily modded Jool-5 a couple of versions ago with a fusion powered SSTO.
25. ## 1.0.2 - Any hope left for SSTOs?

I agree, it was never sensible. But when has KSP ever been about being sensible? Don't get me wrong, it's good that it's at least quite difficult now if not impossible. That's awesome! See this is why I come to these forums, to get ideas when I am hitting a wall myself. This definitely gave me ideas for improving medium-sized SSTOs. (I define medium sized as generally using mk2 hull with 25-75 tons wet).
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