DerekL1963

I prefer to use the Buffalo stabilizer legs that come with Heisenberg. Also note the 'X' stern, helped me avoid slamming my control surfaces into the ground.

But keep in mind it's one guy's informal viewpoint and it's now four decades old... Emphasis on the "informal" and "one guy" - take the second quote above, the Soviets managed to build a number of missiles based on that combination. In particular, both a tactical missile and a SLBM.

To be fair "based off Concorde" isn't quite what the original said. (Actually, if you haven't yet and you need a laugh... you should go read the original.)

How could they have known it at the outset? The design wasn't complete then and relevant calculations almost certainly weren't even started. I wouldn't be surprised to learn the relevant equipment and systems weren't much more than a high level block diagram, a few sketches, and a couple of pages of rough calculations at that point (almost six years ago now). Design and qualification are complex, lengthy, and iterative processes. I'd be surprised if there weren't any surprises along the way. There's probably been more, which we'll never hear about until some SpaceX engineer writes his memoirs in 2050 or so.

If you're not averse to using MechJeb, check out my tutorial - Mechjeb for Airships. You will need to make sure you have sufficient SAS authority and EC. At least two - my Norge uses three.

I've finished testing it, to make sure that a) I can do it (a basic requirement for challenges), and b) that it can be accomplished with no mods other than MJ (since not everyone uses KJR). Now I just need to find time to write it up and post it. (But I also have posts for my anime blog that need working on... and those have hard deadlines.)

No, I want a video entirely like the one you said you made, because it would be very cool. (Well, once you settle on what video you want to make, you claimed two very different ones.) Not really, no - because by not showing the stack, you've failed to provide context. That's the biggest problem here - you swap almost randomly from cramped close in shots to huge wide shots, and completely fail connect them or to provide scale and context. Not really, no. Because you can barely see the rover down at the bottom and in the corner of those shots. (Something I pointed out in my previous message.) Then honestly, there's no point in continuing the conversation. You're not even trying to understand what I'm saying.

If you're looking for someone disingenuous, you need to take a look in a mirror, because is now the second message where you've done nothing but handwave and blow smoke rather than addressing the issues I raised. In other words, it doesn't constitute existing and available technology. Take a look in that mirror again. Again, sidestepping the issues I raised. Seriously, are you so dense you fail to grasp the difference between storage dewars that are already chilled - and your flight tankage which isn't. And the same goes for the flight tankage in the ULA paper you linked. It's pre chilled on the ground. Once again the mirror beckons.

The key here is "monoprop mixture", a more conventional bi-prop may or may not suffer the same problem.

Well, it doesn't really convey that either. You've given nothing which provides any sense of scale, and your constant closeups give the exact opposite impression - of being cramped and closed in. You barely see Duna at all except for one long distance wide shot, and some random shots of the horizon where you can barely see the rover (again, the rover provides scale). Look at this shot (starting at 00:46) to get an idea of providing context and conveying scale and emptiness. I'll quote myself from my earlier post, where I provided the specifics - "You never showed a clear shot of the vehicle at any stage of the process, so it's pretty much impossible to tell what's going on." Watch this video and note how they mix close up shots with long shots to provide context. Especially note the sequence starting at about 3:20 and compare it to the sequence above to see how the provide context and scale.

0.o And how, precisely, do you intend to get the cryo-collection machinery into position without spending propellants or requiring wing area? Cavorite? 0.o Existing tech? Please cite one example of an operating in flight cryo-collection system. 0.o No, you have to hold the oxygen liquid from the moment you start collection.

While the graphic quality is impressive, your shot composition and editing needs work. You never showed a clear shot of the vehicle at any stage of the process, so it's pretty much impossible to tell what's going on.

Back to the game after several months away, downloaded 1.3 and started downloading and installing my usual suite of mods. (Still only about halfway there.) Got liquided that a challenge forbade MechJeb, designed my own version requiring MechJeb, flew the challenge to prove that it's doable... Now trying to decide whether or not to post it. (Basically the challenge is still challenging even with MechJeb, annoyed that so many folks insist on making challenges an eye-hand coordination test rather than an engineering challenge.) Downloaded Heisenberg Airships, messed about checking out all the changes.

No - we do not know it works. It's a completely new engine requiring a fuel with... let's just say 'unusual' requirements. Claiming that the difficulty is on par with a conventional engine is ludicrous at best.

No, it's not 'free' - you pay a great deal of money and weight for the hardware.

Our considered opinion was that is seriously stupid way to go about things. A great deal of mass, volume, and power spent for very little return. LOX is cheap, and so is Al-Li. It doesn't make sense to spend gigabucks developing a system to save a few tens of thousands of dollars. That's the basic problem with a lot of these schemes, the proponents thereof get blinded by their technical brilliance and forget what the point of the exercise was in the first place. As I've long said, "cheap access isn't just an engineering exercise - it's also a beancounter exercise". Thinking about the aerodynamics of that makes my head hurt.

Back in the 90's, on a space newsgroup, we spent quite a bit of time trying to work out how to air-to-air refuel LOX without a) crapping up the LOX system on the receiving aircraft or, b) freezing the two aircraft together where the boom connected with the receiver. (The problem of chilling and purging the boom and the piping on the receiving aircraft to maximize the quality of the LOX that reached the tank we left for another time.) Our semi-professional opinion (as there were actual rocket scientists weighing in) was that it would be an extraordinarily difficult thing to do.

o.0 Why? The issue (outside of the cat pack, a serious and significant development task in and of itself) isn't the HTP, it's the magical-pixie-dust fuel. o.0 Huh? There's a huge difference between a conventional LOX/NOX+Hydrocarbon engine, where you *can* look stuff up - and this Rube Goldberg engine about which darn near nothing is known. Not to mention you greatly exaggerate (or fail to completely grasp) the nature of the difference between the "lab time" (virtually all developmental) required for a conventional engine*, or that (complex research + development) required for this monstrosity. They aren't even in the same league. Apples and the thing least like apples you can imagine. * People build them in their garage for heaven's sake.

When you updated the "rules", you need to edit the first post with the update as well.

It's theoretical ease of ignition - we don't know for certain (or really at all) if it's even possible to ignite and attain a stable burn in the first place. There's a raftload of known unknowns, and who knows how many unknown unknowns.

That's pretty much my point. If you're trying to build on the cheap, and your first step is a complex chemical and mechanical engineering research program to study a completely unknown engine - you're already on the wrong path.

As the Mythbusters used to say - "well, there's your problem". You're trying to use KSP to illustrate a problem it's not equipped to properly simulate.

o.0 I'm not imagining anything, I'm using real world physics. For your fuel to flow, it has to accelerate from zero speed - and that takes time and distance. And the force is only one gee at ignition, which just adds further difficulty - the force flowing your fuel varies radically from ignition to burnout. o.0 A few messages back, it wasn't a gel... and now it's a gel again. Except when you're mistakenly relying on the properties of oobleck to make it once again, not a gel. Seriously, your fuel magically changes properties to magically address whatever objection is being made. And that's setting aside that there's no mechanism creating droplets, let alone driving entrainment and mixing. Feel free to enumerate them.

Well then, this engine is DOA. (Or, more accurately, yet another way this engine is DOA.) No way gravity provides sufficient flow given the small size of your combustion chamber, not with a fuel thick enough that it doesn't simply flow out the nozzle in the first place. Gravity (and acceleration) requires distance and time to accelerate the fuel, and there simply isn't enough vertical height in any practical launch vehicle. Given that this is a hybrid, your chamber is going to need to be ten to twenty times as long as shown in the diagram to provide sufficient burning area. The problem is you have a burning surface of a solid/hybrid rather than the burning volume that a liquid engine has. (Basically, since you don't have an injector for the fuel, you're not going to have efficient mixing of the propellants.) Seriously, I don't grasp why you're stuck on a radical (and extraordinarily unlikely to work) engine design, rather than a conventional (and well understood and characterized) design.

Greenland sits on top of an independent plate.