GoSlash27

KerikBalm, True... but since the entire point of my spaceplanes is to be practical and fund efficient, these avenues are not open to me. Best, -Slashy

Well... the one I posted works from 100% starting facilities. No goo or science Jr, though. I don't carry serious science to orbit until I have unlocked the Terrier. Best, -Slashy

KerikBalm, True, but I would never do that. My objective is to make a cheap reliable "space truck" that's easy to use. I'm not about to compromise that just to make it possible to recover a spent stage that I didn't need in the first place. TSTOs are fun to play around with in sandbox, but I have no use for them in career. YMMV -Slashy

Spaceplanes are strictly a means to an end for me; Get supplies to a station in orbit (and perhaps back to KSC) as cheaply, easily, and safely as possible. Furthermore, spaceplanes represent a large investment of R&D time and effort, so I only design them for "routine" missions; ones that must be flown regularly and do not require any redesigns to fit the payload so that they will recoup that cost. That basically means crews and fuel. Since I run 100% vanilla, anything that drops off during a staging event is lost. Putting all of this together, I don't use TSTO spaceplanes. SSTO spaceplanes are simply better at doing the job I use spaceplanes for. Best, -Slashy

*Sigh*. Ya got me. Going by the law of averages, @legoclone09?

MiniMatt, True... but that was the question that was asked. If you needed to put a kerbal somewhere where you can be sure they won't escape, how do you go about doing it? Just put them on Eve. No need for walls or guards. If we want to go *really* dark, we could always just chuck them down a Mohole or kill them. Best, -Slashy

As the others have said, the trick is to keep your velocity vector overlapping the... Nevermind. Let's just do this instead: https://www.youtube.com/watch?v=5ciFCKgyx48 The important parts are "pushing/ pulling the marble" and the 10x rule for closure rate. Best, -Slashy

foamyesque, I believe it's still possible with RT-10s... but since you get the Reliant and tanks in the same node there's no point in it. Best, -Slashy

Foxster's design is very similar to mine, but I forgo the solid boosters. You can't actually make orbit on your very first launch using only fleas. You run into the 18t pad limit before you can generate enough DV. We tried It's actually much easier to collect science from the pad/ runway, then unlock the science jr,, then repeat, and *then* go to orbit. That way you have better equipment to work with. Me *personally*... I prefer to do my low and high altitude science flights first. That unlocks the LV-909, which makes orbital flights easy. Best, -Slashy

Heck, you don't have to lock them up. Just drop them on Eve with habs and drop them supplies. They're not going anywhere. The Soviets used to do this in Siberia and the Brits did the same in Australia. Not being political, just historical Best, -Slashy

Don't ask. -Slashy

Haha oh, trust me.... Anything I'm doing is within the ability of the average player. I've just done this a whole lot of times and have developed the tools to allow me to answer questions like these without working at it. My strong points right now are "experience" and "laziness" The fact that I'm getting away with this shenanigans really just means that stock career is broken. Best, -Slashy

James M, I have unlocked the entire tech tree without venturing to another planet, but I did scour Minmus and briefly send a kerbal out of Kerbin's SoI. Since the recent rebalancing that feat has become easier. As for the LV-N vs. chemical rockets... actually, not so much. The fuel you save by using the LV-N is offset by the engine's mass, so the ship winds up being heavier. And, of course, a lot more expensive. Say, for example, we want to send 10 tonnes LKO-> LDO-> LKO with aerobraking at each end. Just to simplify things, we won't actually expend any mass at Duna. Kerbin to Duna is 1,078 m/sec. Duna to Kerbin is 623 m/sec. That's a total of 1,701 m/sec round trip (neglecting any reserves). Keeping the t/w at a minimum of .5 kerbin- relative, here's how the 3 options would stack up: Terrier: 2 engines and 18 FL-T100 tanks. Total ship mass 20.8 tonnes, fuel+tank mass 9.8 tonnes. Total stage cost $3,480 Poodle: 1 engine and 3 x200-8 tanks. Total ship mass 22.0 tonnes, fuel+tank mass 10.2 tonnes. Total stage cost $3,700 LV-N: 2 engines and 3 Mk-1 tanks. Total ship mass 21.0 tonnes, fuel+tank mass 5.0 tonnes. Total stage cost $21,650 As you can see, not only is the Terrier a whole lot cheaper than the LV-N for this job, but it's actually lighter as well. The LV-N doesn't actually come into its own until you move beyond Duna and Eve. Of course... if you aren't aerobraking at either end, then it's a different story. Once you get beyond 2km/sec DV, the LV-N becomes lighter and eventually cheaper. I know it *seems* intuitively like the LV-N should beat the daylights out of the other engines because of it's high Isp, but it's a boat anchor and that engine mass is something that needs to be hauled around... and up to orbit. Ultimately, this is a non- issue IMO. Not only because the entire tree can be cleared without leaving Kerbin's system, but because if you *do* choose to go interplanetary, you can easily unlock the LV-N long before the first transfer window to Duna. My current Caveman career is at tech level 6 on day 14, and I haven't even sent a kerbal out of Kerbin orbit or touched down on the Mun yet. Best, -Slashy

Actually, no. The winner was @Nefrums with a quasi-asparagus design utilizing 2 cofiring twin- boars. He got under $600/ tonne. All of the cheapest entries utilized quasi- asparagus staging, where the SRBs carried drop tanks for the core which fed it asparagus- style. Hella- cheap and elegant design, but unfortunately it only works with fairly large payloads due to the cost of decouplers and plumbing. In the case of those parallel designs, we found about 1.6 t/w off the pad to be optimal. Best, -Slashy

Terwin, I'd say we're free to continue on our own recognizance. We all know if we're "cavemanning honestly" and any of us can answer questions from new players. Best, -Slashy

Wumpus, We're probably wandering off into the weeds here, but... The Terrier and Poodle are absolutely outstanding transstage engines, but yeah... if you're trying to use them in the boost phase when the rocket is still mostly vertical and going slow, they're not very good. Once you get to the transition point I mentioned earlier, apoapsis is a long time ahead and the rocket is more horizontal than vertical so you don't need much thrust to keep the show rolling. I design these stages to have 1600 m/sec DV and a t/w of 0.7 if I've got another stage or 1700 m/sec budgeted if I'm going to ditch it at the next body. That's a personal preference thing; I hate having junk floating around up there, so every stage comes down somewhere. As for a Kickback second stage, you could do that... but I wouldn't recommend it. It's still cheap for the DV, but it's weight penalty is so high compared to LF&O that it makes your first stage more expensive, which winds up costing more overall. Plus they can't be throttled, gimballed, turned off, or restarted. This makes them just about useless for circularization burns. Best, -Slashy

Agreed. Also agreed. A tree layout like this would allow a player to start out as they see fit. But of course for this to work, each mode would need access to enough science to be viable. Best, -Slashy

Hevak, Actually, no. The way science is generated is a small part of it, but the core problem (as I see it) is partially the distribution of science, but mainly the layout of the tech tree. The starting tech is way too advanced IMO. Manned rocket launches are half way up the ladder, and a stone's throw away from manned spaceflight. There's a whole lot that could've gone on first that was wasted. The tech tree layout is such that first Kerbal in space and first kerbal in orbit happen almost immediately, and very little choice in how to proceed. By the time you have to start making choices, they aren't critical at the time. None are really great, few are bad, and none are necessary. By the time those choices come into play, you already have them all unlocked and you have enough tech to go interplanetary. It becomes a chore to unlock and upgrade everything, rather than an enjoyable part of the game, and this happens just a few days into the career. Simply changing the order of parts and increasing the options would make for a much more enjoyable career IMO. Also ('nother issue) there's way too much science available at KSC and not enough science available at the other Kerbinside biomes. Best, -Slashy

Yeah, this sounds fair. Plus the issue of changing the tech progression breaking game saves from previous versions. I would be cool with adding an alternate "timeline" career mode to keep everybody happy. Having said that, I disagree that interplanetary flight and exploration is the fun part, at least not in career mode. People have fun all sorts of different ways in KSP, and I'm not trying to dictate to others which parts of the game they should enjoy most. *BUT*... (of course there's a but ) Career mode is intended to focus on the challenges and rewards of developing and managing a space program, not merely launching Kerbals. That part of KSP can be enjoyed in any mode. Career mode is all about developing the tech, upgrading the facilities, keeping the accountants happy, and exploring strange new worlds. I don't think the folks who prefer to play KSP in career mode specifically *because* it is career mode would mind terribly having more challenges in the progression and more options AFA how to tackle them. It is, after all, those challenges and options that make career worth playing in the first place. Best, -Slashy

Yeah, I'll agree with this as well. I find that while I enjoy the process of unlocking the tech tree, I don't need most of what I unlock at the time I unlock it and the game progression becomes pretty linear as a result. I'd prefer to have more options, both in what I can unlock and how I can develop my career, Plus... it'd be nice if it took longer than a few days game time to get from the start to interplanetary flight. IMO the most enjoyable part of career is over almost at the start. I'm probably in the minority on this, but I think it'd be seriously fun and rewarding to have a whole list of "firsts" I could accomplish before putting a Kerbal in orbit. Best, -Slashy

Also... I propose that we don't get mad at each other (or give others a reason to be mad at us) over this. It's just a minor disagreement over a video game Best, -Slashy

^ I agree with this. Nuclear engines don't really become worth the weight penalty until the 2km/ sec mark, and aren't cost effective until much higher than that. LF&O engines are not only practical for Duna and Eve, but are actually preferable. And on top of that, there's enough science in the Kerbin system to unlock the entire tree without going beyond Minmus. Another gameplay problem IMO... Best, -Slashy

moogoob, Oh, by all means there's no apology necessary on your part. That was all me. And I do hope you didn't take anything I said as a gripe about you. IRT your question, yes high t/w has become somewhat fashionable in certain circles, but it depends on what you're trying to accomplish. I've noticed a pattern in the schools of thought about the "best" way to get payloads to orbit that tends to mirror the progression of the individual player. First comes "moar boosters* because that's a running joke around here. Next is most DV you can stuff into a lifter, followed by least DV expended to orbit, followed by highest payload ratio, and eventually ending at "cheapest and most reliable". There may be another tier beyond that, but if so I haven't seen it yet... If you wish to get your payload to orbit cheaply and reliably while keeping it easy to handle, you're not going to wind up putting a lot of t/w in the booster. It'll take more m/sec DV to accomplish the job, but the price tag is reduced and it's easier to fly. Apologies, -Slashy We did nerf the thrust off the pad, as it is necessary in order to tailor the thrust curves over the duration of the gravity turn. Having achieved that balance, the question then becomes one of the economy of adding boosters in order to boost thrust. While adding boosters will improve the DV efficiency (DV required to get through the boost phase), it actually hurts in terms of cost per tonne of upper stage. Even though less boosters requires more DV to do the same job, it still works out cheaper, which is the point of SRBs. On top of this is the balance issue; lower thrust SRBs require less active control to keep them on course. Sometimes no active control whatsoever. This adds to the economy of SRB first stage designs, and makes them much easier to pilot correctly... which reduces launch failures. Finally, there's the issue of using SRBs for a job they're no good at. An ideal first stage is geared strictly towards cheap, so it's heavy for what it does. A transstage, OTOH, needs to be light. SRB propellant is too heavy and the boosters too inefficient for the job. So it's better, in terms of cost, to transition to LF&O as soon as practicable. That means that the DV savings of high thrust are simply employed in a job they're no good at. In theory, this cutoff would be up around 8km @Mach 1.2, but controllability issues usually push this up to 25-30km @Mach 2.5, since it's convenient to dump your fins at this point. TL/DR; So while *theoretically* high initial thrust is good for efficiency, cost- effective and practical designs will wind up cutting that way back. The super- cheap designs generally work around 1.1-1.3 t/w off the pad. HTHs, -Slashy

Weeelll.... I wouldn't be so quick to say that. Aside from the control and heating issues, there's also the matter of how you define "efficiency". While it is true that a high t/w is most efficient in terms of DV expenditure, it is not the most efficient approach in terms of payload fraction or cost per tonne to orbit. Since we're talking SRBs, the overriding concern is "cheap", else we would just go with LFO (which is much easier to work with and lighter). In this case, lower thrust is preferable. See the entries in the "cheap & cheerful challenge" here: All of the high- ranked entries use SRBs and low thrust off the pad. Best, -Slashy

Well... I don't mean to turn this thread into a tirade about Scott Manley and I don't mean to disparage him. He's an indispensable member of the community and he does fantastic work with his tutorials. It's just that he's a teacher, not an inventor or super- skilled pilot. His skills and knowledge are on par with a lot of folks around here, and I can think of several players who are far better. But again... thank Kraken we have him around to teach new players! -Slashy