Northstar1989

OK, so I can't use lengthened fuel tanks because of reduced structural failures- that's kind of fair if it was a 1.25 meter fuselage like the Eagle, but 2.5 meter fuselages aren't very prone to structural failures under the kind of forces they are subjected to here- because they have 4 times the joint strength of 1.25 meter fuselages... So it really wouldn't improve the structural stability in the relevant force ranges. Plus, longer tanks are actually MORE likely to break, because of the higher torques they experience due to the inflexibility of the thing- using 16 short 2.5 meter fuselages I would be much LESS likely to experience a structural failure than using my 4 long 2.5 meter fuselages. The shorter the components the fuselages is made of, the more capability it has to bend without breaking in a spaceplane... Think of it as the difference between trying to break a twig, and break a bendy-straw... (unlike in a rocket- where shorter fuselages lead to less structural stability, due to the tendency for them to "pop" out of alignment with the rest- like happened to the joints next to one of the shortest components of one of my Eagle Mk2's during ascent on a rocket...) As for the landing zone, once again, didn't you only land at that altitude because that's where your Kethane field was? It's not that I can't land at 2500 meters, I'm just saying, why ask everyone else to replicate something you did purely for practical reasons? There are plenty of low-lying areas on that map as I see it... Technically the Kerbals aren't dead, but "Missing in Action"- nobody actually SAW them hitting the ground (and, in fact, the cockpit section that fell off most likely would have splashed down at less than its impact tolerance of 45 m/s in the ocean I was currently over- as I saw precisely this same structural failure in an earlier launch attempt, and the cockpit would glide along doing loop-de-loops thanks to its attached wings, until it landed at about 20 m/s- yet he probably drowned anyways since nobody saw where he landed. The guy in the service module was surely a goner on the other hand.)- but I'm sure that doesn't matter to their poor Kerbal families... It was for a good cause though! Soon, 4 Kerbals will ride down to the surface of Duna on my undamaged Eagle Mk2. The Advanced Spaceplane, on the other hand, may have to be delayed indefinitely due to reasons of lag if I'm not allowed to use the longer 2.5 meter fuselages I created... Which I consider kind of unfair- because the strength or weakness of your computer really isn't supposed to be part of the challenge... (Even currently, with 8 fewer parts thanks to the longer argon tanks, and a part count of 60, the lag is almost unacceptable- and 8 parts more would push it over the edge. The 92 part version I launched with ten 2.5 meter argon tanks and a bunch more control surfaces earlier was so laggy I'm not sure I would have ever been able to land it...)

It won't be long now. Since my last post, I launched two copies of the Eagle on a gigantic rocket (most laggy thing I've ever done) One of them snapped in half in the upper atmosphere (structural integrity was one of the prices I paid for an ultra-low weight design), sending two brave Kerbals plummeting who I can only assume fell to their deaths: (Or not, as the case may be- my "MIA" Kerbals seem to have an odd ability to reappear in the Astronaut complex after a couple more launches- and actually, the one who was in a cockpit theoretically should have been able to steer to a safe landing- as he had two wings and two winglets attached. I'd seen one survive precisely the same structural failure in an earlier launch attempt.) But the other plane made it to orbit unharmed: I circularized the orbit, and put the ship in a nice low parking orbit: And I rendezvoused with my Orbital Fuel Depot (though, as I decided to trust MechJeb to make the intercept, it blew nearly 3k Delta V getting there- leaving me with just over 2400 for the transfer to Duna and capture if I don't perform another refueling before departure) And then placed the transfer stage in a much higher (and thus less laggy) parking orbit- probably to await a fuel tanker just to be on the safe side... For those wondering what happened to the other plane, I dumped it in LKO just after circularizing- the Kerbals will be rescued by a future mission. Unfortunately, though, I have some long-neglected real-life issues to attend to; and I also need to clean up my Kerbin orbits a little before I do anything else- as you can see, it's become quite crowded with ships, and it's certainly not helping my FPS in LKO: (The ship in focus is a nearly-empty fuel tanker, by the way- my Eagle Transfer stage still has simply thousands of units of fuel onboard, and two stock NERVA engines to best utilize it.) I'm sure my Eagle landing won't be all too far off now though. In the meantime, I have a little consolidation and reorganization to do. High on my priority list are scrapping my obsolete (and now empty) Orbital Fuel Depot, and building a lower part-count Orbital Spacedock in a higher orbit (and then scrapping the old one). I also have a couple LiquidFuel tankers in orbit waiting to be used to fill the planned larger tanks on my new spacedock- and then I need to recycle those ships as well. I also need to get that atmospheric scooping ship working... (the last model had WAY too much SAS, making it uncontrollable- so I pulled the 2.5m ASAS module from the design in the VAB, added another LFO tank (so it could carry more oxidizer), and need to get around to building it once my orbits are cleaned up a little. I have enough LiquidFuel in orbit to send large ships to Jool several times over- if I can just consolidate it and get some orbital Oxidizer production (from atmospheric scooping or Mun electrolysis of regolith) going...

OK, so I'm posting the first part of what should be my first challenge run. I got sick of messing with my Advanced Spaceplane designs (as I'm sure you all got sick of hearing about them)- and decided to put that idea on the backburner for a while. Instead, I launched two Eagle MK2's strapped to the side of a 5 meter rocket (which proved surprisingly difficult just to get the editor to let me do- and in the end, I had to settle for a decoupler that clipped into the fuselage of the Eagle's) Anyways, I don't think I presented this version of the Eagle yet (I made some changes, even vs. previous Mk2's), so here's an image of a flight test of the thing on Kerbin: And here's a couple images of the launch rocket with two attached, shortly after liftoff: As it turned out, it was a good thing I attached two of them. Due in part to the extreme lag this many parts created, and in part to the very high torques exerted by all my SAS wheels on the rocket (the Eagle MK2's each had two cockpits with SAS, and the rocket had several wheels of its own)- one of the Mk2's attached to the rocket snapped in half somewhere in the upper atmosphere (one of the cockpits and a service module snapped off one of them- killing two Kerbals). The other half of the Eagle, and its two remaining crew members, however, survived. And one of my Eagles (the one I'll use on Duna) was completely unharmed and intact upon making orbit. The third image also captures a pic of my circularization burn (I relied on MechJeb for this- normally I'd do it myself, but I wanted to capture good screenshots, and it was too laggy for me to control well anyways- but MechJeb seems relatively undeterred by lag.) And an image of the orbital map, in case you didn't believe me when I said it made it to orbit) Anyways, the specs on the version of the Mk2 that I put into orbit: Crew Capacity: 4 Cargo Capacity: 3 tons (LFO, Argon, and Mono-propellant were my chosen cargo- the Eagle uses none of these itself, but I can transfer them to other vehicles on Duna) Max Altitude on Kerbin: >30,000 meters (without cargo), 20,000 meters with cargo (cargo equates to 23% of vessel mass when full) Top Landspeed on Kerbin: .1360 m/s (I stopped counting after this point- the game's equivalent of Mach 4- also without cargo) It should be interesting to see how much better she performs on Duna. My plan is to send the intact plane down to Duna empty first, maybe explore a little, and then send a cargo drop for her to fill up with and carry to my intended airbase (honestly, I doubt I'll land anywhere near that probe to start with- and there is NO WAY I'll be able to target a cargo drop mainly reliant on parachutes and a burst of thrust just before touchdown that precisely...) Regards, Northstar

The spaceplane wasn't coming along as I like, so I focused on developing one of my lighter models of plane I can carry to orbit on a rocket. I present, the final version of the Eagle Mk2, as seen in one of my latest test-flights with a full cargo load: I outfitted this version to carry up to 3 tons of cargo and 4 passengers, and was designed to meet the "Flying Duna" challenge requirements as well. Unlike my spaceplane, this plane is light enough to strap to a rocket. So expect images of one riding to orbit and then Duna that way very soon. Here's the intended initial landing zone, assuming the challenge allows me to land at a lower altitude first: Regards, Northstar

I've been working some more on my SSTDABK spaceplane. So far, it's not ready- but this is what I've developed so far: As you can see, I got rid of the VASMIR thrusters- opting instead for Pulsed Inductive XL Thrusters, which are lighter and produced slightly higher thrust (9.7 kN each) at the expense of ISP. I also stretched the fuselage quite a bit longer with more argon tanks, added a lot more wing area, and reduced the crew capacity from 7 to 5. The idea is to minimize weight, maximize lift relative to mass, and give the thing a decent enough range to hopefully make it require fewer refueling stops... I'm having some stability problems with the longer variants, though (they like to tip nose-up if my angle of attack goes too high)- so I haven't managed to get one to orbit yet... I might have to reduce the crew capacity again (to 3) if I'm going to have any chance of getting the thing out of the atmosphere on Kerbin... (the current design is more than capable of a Duna escape) I also attempted to set up a Microwave Relay Station to extend the coverage area of the Microwave Power Station... Unfortunately, the system seemed to either be bugged, or have a very short range- it refused to pick up the transmitted power from the power station when it was more than a very short distance away... Here it is moving into a higher orbit from the vicinity of the Orbital Spacedock though: The Microwave Relay's probe core is now about to run out of power- I didn't think to charge it before leaving the Spacedock (it has a massive energy storage capacity integrated into the large deployable Microwave Receiver), as I figured it would be able to pick up power in its higher orbit. Unfortunately, this didn't happen- so I couldn't even circularize the orbit, and it's now stuck in an elliptical orbit with a high chance of eventually colliding with the Spacedock, waiting to be scrapped... Once I get the spaceplane to orbit, or a couple of my smaller Duna planes (I've developed a whole fleet of thermal turbojets), I'm going to be sending up a bunch of additional components for my eventual Duna colony- as the transfer window is approaching. Plans include a deployable runway for Duna, a Science Lab to electrolyze Regolith on Ike, and a bunch of RocketParts and a Rocket Workshop to construct more stuff on Duna's surface (including a surface fuel depot near the runway, a fuel-carrying rover, and perhaps some Kerbal "housing" in the form of Hitchhiker Storage Modules)

Here's the landing site I discovered with my light probe a while back (the tiny little thing you can just make out in the center of the screen) Also, as you'll also notice, I've now installed MechJeb (I saw no rules against it). This was to take some of the tedious micromanagement of heading out of the long ascent climbs with my Advanced Spaceplane when trying to escape Duna. Here are a couple images of my latest version (Mk3) using the longer 2.5 meter argon tanks, by the way. If anybody could show me how to weld a bunch (12-16 would be ideal) of the 2.5 meter Arg-100's from the NearFuture mod end-to end to save part count I'd greatly appreciate this. Already, with four of the quadruple-length argon tanks I made, the part count is nearly 60 (the upper limit for what my computer can handle)- and my current model could definitely do with a few more control surfaces- but I'm afraid to add them because it might make my computer too laggy with the current part count...

Thanks for the clarification, that makes sense. It's definitely not for leaving Duna- the plane can easily do that on its own power- and would probably be too far away to get any significant amount of power from my Microwave Station orbiting Kerbin anyways, even if I tried. As part of my long-term colonization plans, I'll eventually set up such a station above Duna- but not now, and it's not necessary for the spaceplane to make a return trip. So, we're cool? I'm afraid you misunderstood what I did. There ARE 2.5 meter Argon tanks- all I did was create a *stretched* variant equivalent to using several end-to-end by up-sizing one of the long 1.25 meter tanks so I wouldn't have to use literally 10 of the short 2.5 meter tanks normally found in the mod end-to-end. I haven't changed the ratio of ArgonGas to mass- so it's essentially the same thing as my design using *TEN* Arg-100's (the tanks already found in the NearFuture mod) stacked end to end. As I showed in the first screenshot, I actually designed such a craft using TEN of only the Arg-100's stacked end-to end, and it flies great except for the lag. If you didn't notice, I've been using 2.5 meter Argon tanks since the beginning- and none of these designs until the latest one included up-sized or in any way altered parts. The mod *DOES* come with a short 2.5 meter Argon tank- which suits my purposes just fine, except for the lag it creates when using a crazy number of them... So, with the clarification, are you OK with this? The difference between welding short fuel tanks, and welding solar panels, is that 2.5 meter fuel tanks can't simply be upsized to create longer versions, as they aren't flat and have three dimensions- and you'll just end up creating a 3.75 meter version instead (I actually did this by accident when trying to create a stretched 2.5 meter version, and kept the mistake for future Argon depots- though I definitely won't be using it in this challenge as it wouln't be legit). So you have to take a smaller version with the desired ratio of radius to length, and upsize it. That's the only way I know of to create a stretched version of the 2.5 meter tank *already found in the mod* at the moment. Once again, using four of the longer tanks is exactly the same as using about 15-16 of the Arg-100's stacked end to end (I made the fuslage a little longer after I could safely do it without adding too much lag.) With the clarification, are you OK with this? If not, I'd be more than happy to simply fuse 16 of the 2.5 meter Arg-100's already found in the mod end-to-end (it would reduce my part count even further- I still have to use four of the almost quadruple-length tanks in my fuselage for my current design) if somebody could show me how. I've got no idea how to do this though, and I have no clue where to find a good tutorial... Yeah, I'm aware of the difficulties in landing. I did scout out a nice flat landing site purely by accident with an earlier probe landing though, and so I'll probably start off just by reactivating the (deactivated) probe as a landing marker, and try landing there first. It's well below 2500 meters though (about 350), so to meet the challenge requirements I'll have to take off again and land somewhere higher... Maybe near the face? It looked pretty flat in that valley there too... It is OK if the *initial* landing happens to be below 2500 meters (if I can manage to make my landing site) as long as the plane can land and take off again at above 2500 meters on future landings/takeoffs- and I make those landings/takeoffs for the challenge- right? I'm pretty sure, form what I read on the Kethane Traveling Circus about the D'OH, that the only reason you started off landing at above 2500 meters is that you couldn't find a good Kethane field at a lower altitude. I'm not mining for Kethane (at least not yet- I might try installing the mod in the future), so I'm really not limited by such concerns. And as I said, I managed to find a much lower landing field with a probe, purely by accident. I'm also pretty sure the area below 2500 meters isn't very large (it's a depression at the end of a valley)- so that's probably why you couldn't find it on your orbitally-constructed map of the planet. I'll post an image of the proposed landing site, just so we're clear, in a second (I've currently got my Mk3 of the Advanced Spaceplane on ascent in the background for another attempt at escaping Kerbin.) If worst comes to worst (I'm horrible at lining up landings anyways), I'll probably just have to make a really careful landing on hilly ground. The spaceplane is perfectly capable of taking a bumpy landing- the problem comes when she tries to take off again, and is accelerating into the bumps- as the wings start bouncing off the bumps at an increasingly fast rate unless I cut the throttle (they have landing gears on them, so the impacts don't break them). This might take a bit more skill and patience on my part, but I'm sure she can get off the ground again after landing too (though, for the reasons mentioned above, she might be best off with a "ski jump" style takeoff at low throttle, kind of like the D'OH) EDIT: I've tried a welding utility- but it didn't work. I tried following a tutorial on welding parts- but that also didn't work with the argon tanks (I think I wasn't setting up the model file pathing or offsets on nodes incorrectly, but I have no idea why in the end). I can't seem to weld parts: although I was able to weld three of the stock Rockomax-16's together with the welding utility, the number for drag and joint strength were way off when I looked in the configs... (and when I tried the argon tanks with the welding utility, it would give much higher resource capacities than that mass of tanks should have- which would kind of be cheating to use...)

OK, so that design didn't work out too well- it couldn't climb past a certain point, and eventually ran out of Argon before making it out of the atmosphere. Convinced that I needed a higher fuel fraction, a lower wingload, and a better TWR; I made the design even longer, and improved all those factors in doing so (the cockpit, crew cabin, and reaction wheel together weigh in at almost 5 TONS- but I don't need more of these no matter how long my plane gets)- and came up with this: By the way, the new design was my heaviest yet- but only weighed about 29 tons total- meaning the payload/cockpit part of the plane was still over 1/6th of total mass... (5.7 tons more were in the turbojet engines, 4.2 tons were in the escape engines and associated electrical systems, 4.18 ton were in Argon fuel tanks- though as I've said, these are only marginally denser than structural fuselages- and the other almost 10 tons were the wings, control surfaces, air intakes, landing gears, wing engine mounts, and a small heat radiator) It flew, but turned out to be a lag machine of death on my weak computer (it had 92 parts). After making it to its peak cruising altitude of 30,250 meters; and max landspeed of 1,080 m/s; I spent a good while dolphining about my maximum cruising altitude, trying to see if I could cruise any higher, and building up as much speed as I could. Then, just as I was about to start my escape burn, I got a really bad lag spike, and the game ended up drastically overexaggerating a minor course correction (I was holding "A" at the time of the lag spike)- leading to the craft entering an unrecoverable tailspin and my reverting the flight... And wasting over an hour and a half of my time (recorded flight time was less than that- but lag slowed the passage of time significantly). Rather than try THAT again, I've followed one of the allowances made here, and fused some parts. Well, sort of. Not exactly sure how to fuse my ten Arg-100 fuel tanks into a giant one, or even fuse two or four together; instead I upscaled the longer variant of 1.25 meter Argon tank by a factor of 2, and increased its mass and resource capacity by 8-fold to match (you get four times the cross-sectional area and twice the length when you upscale 1:2 like that). Essentially, I created a long 2.5 meter argon tank- and after increasing its joint strength to match the other 2.5 meter argon tank (2.5 meter parts normally have four times the joint-strength of 1.25 meter parts, according to the other configs I examined: apparently to match their four times greater cross-section), and giving it a clever description of its own, here is the part- and a WIP on my Mk3 of the Advance Spaceplane in the background: I hope this is allowed- I did it to save part count and lag, though I also found that the upscaled part did not fall precisely into the normal 1:2:4 length ratios of 2.5 meter parts- instead falling in at between 3.3 and 3.8 times the length of the short 2.5 meter variant that NearFuture mod already had (it doesn't have any longer 2.5 meter tanks than the Arg-100's I had previously used- or I would have just used them). Using the longer fuel tanks, I was able to safely extend my fuselage a little longer still without making the part count too high for my computer. I also eliminated all small wing components I could (even though they often have a better lift:mass ratio than the larger wing components- the tiny little Heavy Control Winglet I liked using so much in my previous designs in particular has the best ratio in the B9 Aerospace/Firespitter/Novapunch2 set of mods I am using), instead opting for the larger winglets to try and provide the necessary control. Here is what I've come up with so far for a Mk3- though I don't know if it will fly as well as the Mk2 (which, if not for lag, *certainly* could have made orbit) given all the tiny wing parts I skipped out on that I normally use to fine-tune and optimize my designs... These spaceplane designs are getting unimaginably long, and past a certain point in scaling them up I'm just going to be better off with an LFO-propelled escape system (the minimum weight with which I can build such a system is getting to be only slightly higher than my increasingly large Argon-based systems). Of course, much more of this and I'm just going to abandon the SSTDABK spaceplane idea entirely- it's good enough just to strap a couple of my smaller planes to a rocket and send them to Duna that way... Sorry to keep spamming the posts here. Geschosskopf, let me know if I'm allowed to upscale an argon fuel-tank like that, as long as I upscale the mass and all those other parameters to match- as you said in the rules fusing parts are allowed. I did my best to ensure I wasn't changing the balance at all from just using a bunch of the Arg-100's in a row (or a quad-adapter and a bunch of the Arg-10's, more precisely in this case) If it's not allowed, I'll be a very sad puppy, of course- it's not my fault my computer is pathetically weak (even on my current 54-part Mk3 design, I expect a lot of lag. I get quite a bit of lag on anything over about 28 parts). Regards, Northstar

OK, so my attempt didn't quite work out as well as I planned- even with the aid of the Microwave Relay Station. The main problem I had was that the Microwave Power Station is in a very low orbit- and so loses much of its power to transmitting through low angles into the atmosphere (it transmits up to 85% of its energy when directly overhead, but as little as 1% when it has a small angle and has to transmit through a lot of atmosphere). It also moves position relative to the spaceplane very rapidly, leading to a very small window for the escape burn. Eventually, I am going to need to figure out a way to move the station to a higher orbit- which has no docking ports, no KAS winches, and no KAS connector ports... I could manually attach a radial KAS connector port (the small radial connectors can be added and removed by Kerbals on EVA) as close to the center of gravity as possible, and attempt to tow it with a specialized tug- but I'm more likely just to recycle the thing and build a new one after I move the entire Spacedock to a higher orbit... In the meantime, though, I made some design refinements to the Advanced Spaceplane that might very well allow it to escape Kerbin's gravity *without* an improved orbit for the Microwave Power Station (though I will still need the very limited assistance a low-orbit microwave power station can provide). First of all, before I present the new and improved Advanced Spaceplane Mk2, let me present another craft I've been working on. I present, the 'Eagle Mk2': Here she is shortly after takeoff: And here she is during the high altitude portion of that test flight: Unfortunately, she didn't nearly reach peak altitude or speed (she reached about 27,000 meters and 1,080 m/s) though, as I left the game running unpaused for a bit to quickly use the toilet, and when I came back her angle of attack had climbed to a level she was incapable of controlling at that altitude. However given her *VERY LOW* angle of attack to gain both speed and altitude at the same time even at over 25,000 meters, I suspect she will easily shatter my height and speed records for the Eagle Mk1. Her biggest weakness is that she has very little control surface relative to her wing area- which means she can easily lose control if her angle of attack climbs too high in the lower part of here altitude range. And by "lower", I mean anything below 30,000 meters (she can probably reach at least 40,000- on par with my best jet planes). And by "high angle of attack", I mean anything over 18 degrees below 28,000 meters. As you can infer, I *MIGHT* need to make some control refinements before she's ready for Duna. Anyways, my main focus has been my spaceplane designs. Here is the Advanced Spaceplane Mk2 shortly off the runway: And here is the launch window I used. Bad timing as always- I'm going to need to get this down to more of a science... Now, about the Mk2: The main insight I had was that the engine weight was greatly decreasing the plane's performance, and was such a significant fraction of plane mass that a light, less powerful engine could actually IMPROVE the TWR- and as it so happened, I had one available that was both lighter and more powerful, but achieved much less ISP and required more electrical power... The Pulsed Inductive Plasma Thrusters XL, from NearFuture Mod, namely. They use ArgonGas, like the VASMIR engines, but weight less than half as much. They consume 10% more power per second though, and achieve only a bit better than 1/3 the ISP (around 2400 instead of 6400). However, I realized my escape burns were taking so long (10-15 minutes) that I could GREATLY reduce total power consumption with a more powerful burn- even if it was less efficient with the electricity. The engines I used were only slightly more powerful (9.70 kN instead of 9.60)- but their reduced weight (2.4 TONS of weight savings when using four of them) meant my entire craft was significantly lighter, and the TWR much better. My other insight was that I could still benefit a great deal form additional wing area. First, some tweaking with the Advanced Spaceplane, and then seeing how well the Eagle Mk2 performed with its additional wing area vs. the Eagle Mk1 (which was previously my lowest-wingload design yet), convinced me of the need to add additional wing area to the spaceplane. The additional wing area has three main benefits: Firstly, by raising my altitude ceiling on turbojets, I raise both my max landspeed before activating my plasma thrusters, and the amount of amount of atmosphere I need to escape though. This means a shorter escape burn, allowing for more rapid power consumption during the burn. Second, and this was not lost on me, then entire point of the spaceplane is to perform well on Duna. If more wing area raises altitude ceiling on Kerbin, it DEFINITELY will on Duna (where the lower gravity means the ideal winglaod is even less than on Kerbin). Third, it helps with touchdown velocity. The less wingload my plane has, the slower it can touch down on Duna. I had already previously thought about trying to add a third turbojet to the craft, but had decided against it for precisely this reason- even if it raised my altitude ceiling on Duna and Kerbin, it would definitely also raise my touchdown velocity by a lot. So, I added as much additional wing area to the craft as I could cram in. I even ignored matters of appearance and extended some trailing edges beyond the edge of my main wings, due to the inability of the editor to allow me to place additional trailing edges along certain points of the wing without them angling inwards at an inappropriate angle... I've currently had the Advanced Spaceplane Mk2 in a long cruise near max altitude while I wrote this, waiting for the Microwave Power Station to come into position. I'll be trying to escape Kerbin soon- and this time I think it will work. I have a good feeling about my new design. Here she is at a high cruising altitude (not quite max) by the way. The previous design MAXED at a bit over 16km without plasma thrusters: And as you might notice on the image, I see the Microwave Relay Receiver dish has just opened- which means my Microwave Power Station is sufficiently close to transmit, and it's past time (a good bit late, in fact) to begin my escape burn... See you guys in orbit- on this attempt or the next (as I said, I should have started the escape burn BEFORE the station was overhead- so it might not make it this time around.) Regards, Northstar

OK, so it's not been long since the last one- but I've already got another update. First of all, remember that Nuclear Science Lab I put in orbit earlier? I certainly do. Well it turns out it has a fuel routing problem- apparently one of the pieces in the stack between the liquid fuel tanks (the two that AREN'T separated by decouplers from the rest of the ship) and the 3.75 meter Thermal Rocket Nozzle (the HUGE engine at the bottom) isn't fuel-crossfeed capable. So, after going through all the effort to launch that thing into orbit over Kerbin, it looks like my plans of sending it to Jool are at an end. Of course, I only discovered this AFTER I started a burn towards the Mun for a gravity assist towards Jool, and had burned out and decoupled what was left of the ascent stage. So, I F5/F9's (I mean, if this was for real, somebody would have noticed something like that the engineers forgot to run fuel pipes to the main engine, right?), and instead docked the Scrapper Ship- which was running low on fuel by the time it got to that orbit (which had a lot of other debris floating it it anyways) with it and drained msot of the remaining LFO mix to fill all its fuel tanks. Here it is docked with the Nuclear Science Lab via KAS winch (hard to see the fuel/winch line against the dark of space, sorry about that) Then I burned out what was left of the ascent stage to bring the Nuclear Science Lab to a little bit of a higher orbit (it produced more Science the further it is away from Kerbin- and I get also get a lot less lag at higher orbits), decoupled it, and then recycled that stage with my Scrapper Ship- completely filling what was left of its storage space for RocketParts, and probably wasting a good bit of of the value of the ascent stage as well. Anyways, it looks like maybe I should have built a Scrapper Ship with more storage capacity for rocket parts- currently it can only hold 25 tons of them, and it takes so much fuel to bring it back to the Orbital Spacedock that I still haven't gotten around to it yet... I'll probably be upgrading the Orbital Spacedock to a bigger, better version with a lower part count anyways (and no giant Thermal Rocket Nozzle- which I built to help get it to orbit making use of the reactor/generator I already had included, thinking the Science Lab would only run on a Nuclear Reactor. Turns out I was wrong about that- it can at the very least run on a Microwave Beamed Power Receiver as well, if the resource it consumes is Megajoules, and maybe even just on a huge solar array if it is capable of running on enough ElectricCharge- it needs 5 Megajoules a second to run research at its full trickle- which equates to 5,000 ElectricCharge per second.) and so maybe I could haul the existing Orbital Spacedock to a higher, less laggy orbit after the new one is constructed (or, just recycle the thing- I don't need too many flights in progress lagging down my computer). Right now, with its current part count, current low orbit, and my weak computer, the lag when the thing is being refueled (and both ships are loaded) is absolutely crippling... In the meantime, I also sent a heavy tanker I designed to carry RocketParts to the Orbital Spacedock. Here is what I *think* was a screenshot of the Rocketparts Tanker during its ascent: Here is an image of what is definitely the tanker in-orbit: And here it is on final approach and docking with the Orbital Spacedock After getting that heavy load of RocketParts to the Orbital Spacedock (nearly 100 TONS of RocketParts- enough to build several very large rockets in-orbit, since that equates to Dry Mass for the rocket- if only I had enough fuel in the spacdock to fill said rockets up...), I immediately put some of the solar panels in the parts shipment to good use (OK I'm roleplaying- the game doesn't distinguish solar panels from metal to build giant fuel tanks- they all cost RocketParts) building a large Microwave Power Transmission Station in-orbit: Now, some of you might be asking- what is that thing, and what is it good for? Well for those of you who didn't play SimCity2000 and 3000 when you were a kid until your face turned blue, a Microwave Power system is one that collects solar energy in-orbit with a gigantic solar array, like the one I built there (makes sense so far, right?) and then beams the power to a target in the form of a phased beam of microwave energy- where it is converted back into electrical energy For those of you wondering what that had to do with SimCity, in the 2000/3000 versions of the game, Microwave Power was one of the more advanced options for powering your city- featuring a lack of any pollution production, and much higher energy density than conventional solar power on the ground- but also a MUCH higher financial cost... The big, gridiron-looking thing on the top of the image here is the Microwave Beamed Power Transmitter- it's what allows that solar energy to get wherever I need it (with some not-insignificant transmission losses, of course). The smaller looking thing on the bottom is just a Yawmaster Service Module (it's the lightest enclosed way to hold a single Kerbal in-orbit, in terms of Dry Mass; and it also features a bit of room for LFO mix, Monopropellant, and ElectircCharge storage)- and is mostly just for the electrical storage and roleplaying purposes. Now why would I go through all the trouble of building such a thing out of my hard-earned (or rather, hauled) RocketParts, you might ask? Well, remember that spaceplane I showed you a teaser of before: Those four blue-colored engines at the back are VASMIR Plasma Thrusters. They take ArgonGas, and a lot of ElectricCharge, and combine them for a very high ISP (over 6400) and modest thrust of 9.6 kN each. I designed my spaceplane (which I am *still* simply calling "Advanced Spaceplane"- somebody propose a better name for it before I just name it after another type of bird; like I did the Eagle, the Egret, and in a previous stock-only save the "Falcon's Nest" and "Rooster's Nest"- which were just glamorized fuel depots with a bit of roleplaying as space stations.) to use four of them (at 38.4 kN of thrust) to escape Kerbin's atmosphere. Normally, I'd use something more powerful for a spaceplane- like LFO mix or at least LiquidFuel on a Thermal Rocket Nozzle- but this one is designed to fly on Duna, and so needs to be as light as possible to minimize wingload. An ArgonGas propellant system was one of the lightest-weight options: due mostly to the very high ISP ratings of VASMIR Plasma Thrusters, and the very low Dry Mass of ArgonGas fuel tanks (actually several times lighter than a 2.5 meter fuselage when empty, and only marginally heavier by length when full of ArgonGas). The thrusters were kind of heavy, of course- weighing in at a solid 1 ton each- but it was worth it considering the weight I saved vs. hauling around at least 2 or 3 tons of LFO mix. The total increase in the mass of the plane, vs. using structural fuselages (the thermal turbojet engines, while they require rather heavy reactors, use no fuel) was about 5.4 tons. Not bad for a system that not only gets the plane to orbit, but carries enough impulse to bring it all the way to Duna without a single refueling! (if I wanted to cut down weight further, I could use a partial load of ArgonGas- and reduce the mass increase to only about 4.4-4.2 tons while still having enough to make orbit, the full-load weight of ArgonGas being a little over 2.09 tons. The plane uses half its ArgonGas just getting to orbit.) One of the other advantages of the system was the extremely low cost of refueling- since ArgonGas gets such high ISP's, I wouldn't need to haul nearly as much of it out to Duna for a refueling trip if, say, I was to use the plane for repeated trips to Ike and back to support a colony there... Unfortunately, the Advanced Spaceplane doesn't have quite enough electrical generation capacity and storage to make orbit as was (1 ton of the 5.4 tons extra mass, besides the 2 tons of Argon and 4 tons of thrusters, minus about 1.6 tons of weight saved in fuselages; was the inclusion of two 0.5 ton electric generators on the plane- which produce power from the nuclear reactors when they're not being fully used to power the thermal turbojets, and when "spun-up" on the runway before liftoff, can store an immense amount of electricity in the form of stored mechanical energy.) So, I decided rather than carrying a bunch of heavy solar panels on the plane, or a huge weight in batteries, or switching to a heavier LFO-based propulsion system; I'd put the extra needed electrical generation capacity in orbit and just beam it down to the spaceplane as it attempts to escape the atmosphere (it still needs a receiver dish for this though). This should also have immense utility with any other craft I build that relies even partially on electric power systems- ranging from electric propeller aircraft (these I have conventionally had to power by making them carry their own solar panels- greatly increasing their wingload and reducing their already low TWR, lowering their altitude ceiling as a result) to VASMIR-lifted light rockets (VASMIR plasma thrusters till get a decent ISP in-atmosphere). In fact, the possibilities for use of the technology are nearly endless! (An aside for those who are curious: thermal generators usually store such mechanical energy in "flywheels"- disc's that spin rapidly in a vacuum chambe, often on magnetic ultra-low-friction bearings- and the kinds of energy storage density you can achieve with this technology immensely exceed batteries- leading one company in my home state of Massachusetts to pioneer their use as energy storage for "smoothing" the electrical grid at a much lower cost than any existing methods. The company is called "Beacon Power", and I highly recommend looking it up...) Anyways... Writing about all this has given me an idea on how I might save even more weight on my spaceplane (the NearFuture mod also introduces a couple other types of argon-propellant thrusters besides the VASMIR ones. One of them achieves a slightly greater thrust than the VASMIR of 9.7 kN, and weighs less than half as much- though at the cost of a huge reduction in ISP, and increased electrical power requirements.) So, if this design doesn't work, I'm going to have to try something like that- though, while the spaceplane is currently capable of escaping Duna's atmosphere without the assistance of a Microwave Power Station in orbit nearby (its generators store enough energy to escape the lesser gravity and shorter atmosphere), it wouldn't be able to if I used a more power-hungry design: so I'd have to think carefully about that or whether I should just try and go with LFO mix after all... Regards, Northstar

The problem is, it's a blurry distinction between airplane and spaceplane with this particular model. Whereas most spaceplanes reach orbit by pointing their nose steeply up, and raising their apoapsis above the atmosphere, that's not how this one works. Instead, at least in flight tests on Kerbin, it keeps gradually raising its altitude, and raising its periapsis instead- always near peak altitude- and keeping just barely enough thrust for the wings to keep it climbing very slowly. Its TWR is so low that it is incapable of reaching an actual ballistic trajectory- it can never climb much faster than 10-25 m/s. Technically, it's a super-high altitude plane with the plasma thrusters engaged: and simply is capable of flying at the very edge of the atmosphere. Normal planes can't do this (at least in KSP *without* FAR installed- it is possible with a Blackbird-style plane with FAR installed as drag falls off in FAR at hypersonic speeds), as their jet engines start to lose thrust above a certain altitude, eventually being unable to cancel out drag and the component of lift slowing the plane down. But plasma thrusters don't- they work equally well at all altitudes, though their fuel (argon) consumption drops as they climb higher. They also don't heave nearly the kind of potential burn times that an argon-plane does (this thing could run its engines for something close to an hour at full thrust). Technically, it is always mostly aerodynamic lift holding it up (it has a very low wingload)- as relative gravity falls off the faster the plane flies, allowing the exponentially decreasing lift to still hold the plane up. That being said, it also has a minor component of its (very weak) thrust holding it up- as it always has its nose pointed well above the horizon in the uppermost atmosphere, very close to 45 degrees (to maximize lift, which hits a peak at a 45 degree angle of attack at a given speed). But as I said, the TWR is much, much less than 1 at almost all altitudes. Only in the last ten thousand meters or so of atmosphere, when its speed has climbed very high (and relative gravity is thus very low) is its effective ratio of thrust to gravity (TWR in its most literal sense- though many players use the term in change of thrust-to-mass ratio in stable orbits in space: where objects have mass, but no "weight") actually high enough to enter a ballistic trajectory. This, as you can see, kind of blurs the line between spaceplane and plane: at what point (other than where the atmosphere completely cuts out) do you consider a plane to truly be in space? Long tangent aside, I haven't developed a rocket to carry the Eagle to orbit yet- but I did construct a Microwave Power Station (I mixed up my terminology before: Microwave *RELAY* stations are for bouncing the energy to reach places the power station doesn't have a direct line of sight on. KSP Interstellar adds these too- although I don't have any constructed at the moment). Here's an image. A couple design notes first though: The thing on the very bottom is a Yawmaster Service Module. It's the lightest weight (measured in Dry Mass) possible way of holding a single Kerbal (inside- not on a lawnchair) in orbit, and also holds a tiny bit of LFO mix, Electricharge, and Monopropellant. It's technically unnecessary, but mostly for roleplaying "maintenance" and crew storage in emergency purposes- such as if I manage to strand another one of my LFO-fueled spaceplanes in LKO. Above it is an inline heat-radiator: for dealing with WasteHeat produced by the solar panels. The thing on the top is the Microwave Power Transmitter- that's what beams the power down to my Advanced Spaceplane. It doesn't need to be facing the target to work correctly. Finally, the panels themselves are 8 "Megalador Solar Panel Arrays" from the NearFuture mod- basically they're just like upscaled, slightly more mass-efficient, but even more fragile, stock Gigantor XL panels. This thing produces 576 kW of energy and is capable of relaying something like up to 91% of that when directly overhead (when the Advanced Spaceplane is landed)- but falling off exponentially with distance to the spaceplane and distance through the atmosphere... So I over-estimated the transmission losses and greatly over-engineered the thing. That should be more than enough power to give my Advanced Spaceplane the extra push it needs to get to orbit on Argon- and maybe even enough to run a hydrogen propulsion system, though I have no intention of trying that yet, as, though it would improve performance; it would greatly increase the need for refueling stops on its round trip to Duna. Here is the launch window from Kerbin I am about to use- as you'll notice, the relay station is still well behind the plane on the horizon. It take a little more than one orbital period for the Spaceplane to reach maximum altitude from liftoff- so if I've timed this right, it should have the maximum period of time after it starts its escape burn with a line-of-sight on the station... Duna is also very nearly to a good transfer window on the solar system map- which gives me a bit of time to refuel and get the spaceplane into a good orbit around the Mun (that way, I can store a large amount of energy in my Munar orbit, and won't need quite as much thrust to make the transfer), but not so much that my Kerbals will be waiting forever... I'm about to begin (after a quick shower, dinner, and an update to my Missions Reports thread) what should be, if all goes smoothly, my first challenge run. I'll let you know how it goes and post a partial update after the spaceplane has reached LKO.

Not much to report here, but some great images of my refueling mission to my Orbital Spacedock and Orbital Fuel Depot here. First of all, the approach: A great lengthwise view of my spacedock while trying to remember where I left the KAS winches on the thing: An EVA to connect the tanker to the Orbital Spacedock: The two vessels finally docked: One last pic, shortly after topping off the spacedock and retracting the winch: And then the tanker headed off to rendezvous with my Orbital Fuel Depot: Arriving at the fuel depot: After running the fuel line to the tanker: And finally, the two craft pulled closer together, as I left them after finding the fuel tanker had a tiny bit of fuel left- but not enough to make itself useful (I'll probably come and scrap it with my Scrapper Ship when the two vessels are in position for the Scrapper to make a rendzvous burn- the Scrapper Ship needs to make a refueling stop by the depot anyways...) Sorry it's not too much of interest today- I've mostly been working on a SSTDABK (Single Stage to Duna and Back to Kerbin) spaceplane design that's still not ready yet, for the 'Flying Duna' challenge. Really cool stuff there- you'll get to see me put B9 Aerospace's giant wings, NearFuture mod's VASMIR Plasma Thrusters, and KSP Interstellar mod's Thermal Turbojets and Microwave Relay System all to good use- with the end result being a craft that can fly to Duna and back on its own (given a bit of refueling), and is capable of an unlimited service life on Duna (as long as it is provided with a KSP Interstellar mod Science Lab to reprocess its Depleted Uranium Hexafluoride at regular intervals). Here's a teaser- an image of an earlier version of the plane nearly making it to orbit during a test flight (it has a VERY slow climb rate out of the atmosphere- but it remains steady and slowly increases as it gains altitude. It made it to about 32,000 meters before it ran out of electricity on that attempt.)

One last thought Geschookpf- and I'm breaking this into a separate post, so as to try not to break your train of thought: The NearFuture mod engines are indeed very difficult to use properly on their own due to their very high electrical consumption and the inadequate solutions Nearfuture mod offers to power them (some slightly better solar panels, and some nuclear reactors that *slightly* exceed the stock solar panels in terms of EC/s per ton of mass- and Capacitors, which are the mod's best solution to the problem for a sufficiently large craft to use them properly). However KSP Interstellar mod offers some excellent solutions for power energy-hungry engines like these: ranging from the nuclear reactors with a massive generation and storage potential relative to mass (but very high mass, and the requirement for UF6 fuel), to the Microwave Power Relay system, which is an actual technology that is being developed and is currently still in theory stages here on Earth (actually, all its technologies are- even the Alcubierre Warp Drive is a rel-life idea scientists have proposed and are debating the plausibility of), and is quite well-balanced in terms of gameplay as far as I can tell (wait until you see how big and bulky my Microwave Relay Station is- and how little power it transmits relative to its enormous size and mass). Using KSP Interstellar's technologies (the thermal turbojets and the Microwave Relay system), I found I am able to put the NearFuture mod's ArgonGas engines to good use- on a SSTDABK spaceplane at least (the whole system is overly complex and barely provides enough thrust to escape Kerbin, but is incredibly lightweight- which is an absolute necessity for the spaceplane to actually be able to FLY well on Duna with only the thermal turbojets active...)

Some good points there Geschosskopf. By the way, it takes me a while to type my posts, and I do tend to type them very fast. Also, if you watch as they appear very carefully, I don't make them all in one go- I often write something, post it, and then edit in more writing 10-30 minutes later after doing something else in-go. Or just keep the reply editor window open the whole time, and refresh the page right before posting. Anyways, I'm really not sure I want to launch all FIVE plane design to Duna. Especially because, after some further thought, I've decided that the 'Firefly' is pretty much a death-tap on Duna- due to its very high landing/takeoff speeds (it would be a good choice for somewhere with a thicker atmosphere, like Eve, however). I'm also not so sure I want to launch the original 'Egret' design, when both the 'Eagle' and 'Egret 2' are essentially improved versions of it that took some aspect of its ability to stay in the air- either its thrust system or its low wingload- and improved it, in both cases without adversely affecting the other parameter by much (the Eagle actually has a better TWR, as well as lower wingload. The Egret 2 has a much higher TWR, but mildly higher wingload). I'm partial to using the Egret 2 for utilitarian purposes (read: transportation of cargo- probably by replacing the structural fuselage with a fuel tank or cargo bay of the same length), but the Eagle for passenger transport and 'winning' the challenge- since on Kerbin it outperforms all my other craft, especially the Advanced Spaceplane (if I can ever get it to orbit- my Microwave Relay Station is designed, and all I have to do is construct it at this point), in terms of turbojet-only altitude ceiling and thus Challenge Points; and due to its lower weight and nearly identical total lift, it's also a little bit easier to get to Duna than the Egret 2. Unless... Does a spaceplane get the 'bonus points' for a higher altitude ceiling during the portion of its ascent where it is still in aerodynamic flight, but is using all its engines? Normally, I'd see the answer being NO, but the Advanced Spaceplane has such weak TWR, even with all engines active, that it essentially has to remain in aerodynamic (rather than ballistic) flight for 10-15 MINUTES with all engines active (yes, you read that right- the ArgonGas lasts a really long time...) before it reaches the point where its thrust is sufficient relative to gravity and drag to set the thing on a ballistic trajectory... It is capable of circumnavigating Duna several times with its ArgonGas engines active in addition to the Thermal Turbojets- provided it has enough electrical power. For this same reason, and the incredibly fuel-efficiency they provide, I will probably use the Plasma Thrusters as an additional boost just to boost climb rate or ensure I can safely climb over particularly tall mountain ranges on Duna... The generators are capable of recharging in-flight, if I deactivate the Plasma Thrusters and dial the thrust back down a tiny bit later on, so there's no worry that doing this too much would eventually lead to engine failure and the spaceplane dropping out of the sky...

Ok, first of all, I want to start off by apologizing if I sounded like I was being a little meant to Sirine in my last post. She sent me a very nice private message apologizing, and said the word "weak" doesn't mean the same thing in her culture- so apology accepted. Anyways, it turns out my Advanced Spaceplane *WAS* just a little too weak to escape Kerbin's atmosphere with only two plasma engines- so I upgraded it to four! Unfortunately, while it did (just barely) have enough thrust that it looked like it probably would have escaped the atmosphere, it didn't have enough stored electrical and mechanical power in the generators to run four VASMIR Plasma Engines for that long- my plane was only able to run them for about 10-12 minutes, and climb to a peak altitude of about 32,000 meters again before they power ran out (they each require 120 ElectricalCharge a *SECOND* at full thrust!) even with a full spin-up cycle this time. This is an image of the four-engine version shortly after takeoff on Kerbin: And this is an image of it about a minute before it ran out of power (the vast majority of which is stored as Megajoules- not Electric Charge) during the burn: The spaceplane definitely DOES have enough power to make it out of Duna's atmosphere in its current state (especially since I found that, when the thrust is dialed slightly back, the reactors have a bit of power to divert to the generators- allowing me to top them off just before my escape burn, as the energy systems do slowly lose a bit of power over time with the drain of both the SAS and full-throttle thermal turbojets...), as the scale height is much less- meaning the atmosphere falls off much more quickly; the gravity is lower, allowing for higher cruising speed before the escape burn; and the plane was able to reach a peak speed during the burn on Kerbin that was in excess of the minimal required orbital velocity on Duna (950 m/s at 42,000 meters, the atmosphere ends just a couple hundred below that- my plane exceeded 1200 m/s with an upwards component during the burn). So, I basically have three options at this point. Option A: I abandon using Argon for the escape system entirely. Currently, the whole thing has a mass in excess of the fuselages that would replace it of about 4.2 tons- a solid 4 tons of which is in the engines (the ArgonGas being very light, and the tanks having an incredibly low dry mass when empty- to the point where I could save a lot of mass on my spaceplane by using empty ones as fuselages...) I MIGHT be able to achieve better results with a similar, or slightly heavier, escape package based on a stock NERVA engine- but wouldn't have any fuel left after reaching orbit, and would have to refuel (though I'll probably also do this with the Argon too- just to be sure I have enough fuel for the return trip). The NERVA engines also have the very worrisome problem of tending to overheat and explode if fired for too long in-atmosphere. Option B: I abandon the single-stage to orbit part of the idea (and lose the potential points) and just try and strap the thing to a rocket. It has a lot of mass and lift for this though, so I doubt it would work on all but possibly the largest and most complex 5 meter rockets. Option C: I make use of another feature of the KSP Interstellar mod, besides the nuclear thermal turbojet engines- and construct a microwave relay station in orbit of Kerbin to provide the spaceplane with extra electrical power during ascent. This would be sure to work, with a sufficiently powerful relay station- as the spaceplane did just barely have enough thrust to escape Kerbin already. Actually, this option has another even greater advantage- it would allow me to upgrade the spaceplane by replacing its Argon propulsion system with a hydrogen one- which is even lighter and generates a lot more thrust (147% more per engine, to be precise), but requires even more massive amounts of electricity. The main advantage of the Hydrogen thrust system is the lighter weight, and thus improved in-atmosphere performance on Duna. The disadvantage of this system is that HydrogenGas' very low density allows me to pack even less Delta V into the spaceplane- not nearly enough to make it Duna and back without several refueling trips- likely one after reaching orbit, one in orbit of the Mun, one on the ground on Duna, and one in orbit of Duna before returning. But hey, the challenge requirements never specified that a SSTDABK plane had to make it all on one fill of fuel, did they? Besides, hydrogen is very light- meaning it would take VERY little energy for me to set up very high-volume depots of the stuff at all of these locations (enough to refuel the spaceplane two or three times each), with my existing lifter designs. The hydrogen propulsion idea would also require a much more massive microwave relay station (the existing spaceplane propelled into orbit by Argon would probably only need a relatively modest microwave relay station in orbit of Kerbin to provide it with the extra power to make it to orbit- though I'll probably over-engineer the station anyways, just to be safe). It might also very well require an additional such station in orbit of Duna- since the hydrogen engines are so power-hungry. The existing argon-powered spaceplane could could escape Duna just fine even without any help, on the other hand- and might still be able to receive a very small amount of additional power from the station in orbit of Kerbin during the transfer window to make a return trip there- if the transmission losses aren't too great over that distance. Once again, I need some input- about a good way to get the spaceplane to orbit- are there other options I haven't thought of? Right now, I'm planning on going with Option C, the Orbital Construction mod, and my existing spacedock, to set up a massive solar power plant/ microwave relay in orbit of Kerbin- constructed partly out of recycled scrap metal from orbital debris, and partly out of additional RocketParts I'd send up (which I guess would represent the actual solar panels in the station themselves). The spaceplane itself would be constructed on the ground on Kerbin, of course- but nowhere in the challenge requirements does it state that any space stations or fuel depots that support the mission (which is essentially what this is) need to be constructed on the ground or launched to Kerbin orbit in one piece- especially ones I won't ever even be docking with. Maybe I should just abandon the whole spaceplane thing, and stick with my existing designs (the Egret 2 or Eagle)- which can fly a lot higher on Kerbin (and thus also on Duna) than the spaceplane anyways (which only can hold 21,250 meters on turbojet power alone on Kerbin with two VASMIR engines attached for escape, or a bit over 16,500 with four)- and in the case of the Eagle might even be able to perform suborbital hops based purely on its turbojet power on Duna, without any assistance (though the usefulness of this in returning the vessel to Kerbin- if I ever wished to do so- is highly questionable). Advice is welcomed. Regards, Northstar

OK, first of all, you need to chill. And stop insulting people. I've come across your posts littering many of the forum threads I've read, and they're almost always negative, they almost always put people down. The planes aren't supposed to be infiingliders (which is what you're describing), and they're not out to break speed records on Kerbin either (if they were, I would be using traditional turbojet engines). I've designed MUCH more powerful planes that can fly on Kerbin before. But the point of this challenge is to fly on Duna, not Kerbin- and at that to do so reasonably sustainably (i.e., even if it can fly there, a rocket-powered plane would require frequent refueling- and so is a poor idea on Duna). Anyways, @ the rest of you. So, putting aside the smaller, lighter designs that can be strapped to the side of a rocket in 2x symmetry with relative ease, I decided to just go ahead and build a SSTDABK (Single Stage to Duna and Back to Kerbin) spaceplane for the job. First of all, I decided to go with a 2.5 meter fuselage as the base- since I recently developed the tech node for the gigantic B9 mod wings, but found that they require at least a 2.5 meter fuselage to attach stably. A 2.5 meter fuselage allowed me to accommodate the heavier wings- which in turn meant I could support more cargo mass or crew capacity. Now, I've traditionally had problems with the weight of my LFO-powered spaceplane attempts, even on Kerbin. I only recently developed my first functional spaceplane (see my Mission Reports thread for images of it), and it is based on a Mk2 fuselage- which is basically just a wider version of a 1.25 meter fuselage that allows a little more room for wing attachments and is wide enough to accommodate two rear-mounted engines. Even the best designs are inherently limited by the low efficiencies of chemical rockets, and the stock NERVA designs are dangerous and unreliable thanks to the engines' tendency to overheat and explode when fired in-atmosphere. However, I'd been playing around with NearFuture mod's Argon propulsion systems for a while, trying to find a good use for them. I find their high electrical power requirements require a very substantial mass in generation capacity to meet- and as the fuel is very light and low-density, and the engines using them have proportionally low thrust, this extra weight tends to greatly impact the efficiency of the designs and not leave much weight for payload. Thus, previously, I had only thought them useful for launching very, very lightweight probes into orbit using the VASMIR thrusters (which work comparatively well in-atmosphere), or as upper-stage transfer modules for still comparatively light payloads (due to the low mass of ArgonGas held by even the largest of the mod's argon tanks, it is difficult and unwieldy to get enough fuel mass into orbit to provide the necessary impulse for long-distance transport of heavier payloads, even with ArgonGas systems' amazing ISP values. Remember, total impulse = ISP * fuel mass.) However, a spaceplane is supposed to be relatively lightweight, and does not suffer as much from carrying heavy masses anyways- as aerodynamic lift rather than thrust is the main thing used to counteract gravity. Plus, the larger ArgonGas tanks are so lightweight that they actually make reasonable fuselages in themselves in terms of their ration of mass to length and attachable surface area. So, I designed the spaceplane pictured here-which I currently am simply calling "Advanced Spaceplane", but will come up with a better name for soon... Here she is shortly after taking off the runway: She features a crew capacity of 7, two thermal turbojets, and 2 VASMIR Plasma Thrusters. The plasma thrusters burn argon, and work relatively well even at sea level (ISP= 250), but are intended for use in the upper atmosphere to push the plane into orbit, where their ISP exceeds 6400. I packed five of the largest ArgonGas tanks into the design- for a little over 1.74 total tons of fuel (still not much in absolute terms- but the Advanced Spaceplane is very light, so more than enough to at least carry the thing to Duna if I use the Mun for a gravity assist- maybe even enough for a return trip without refueling if I use Ike the same way.) What's more, and the main reason this design is efficient- the plan is already carrying two 1.25 meter nuclear reactors to power its thermal turbojets, so all I needed to do to provide electrical power for the plasma thrusters was to slap an electrical generator onto each. Now, one thing that I absolutely have to point out about the design- you can't get something for nothing. The electrical generators don't spin up any further when the thermal turbojets are running (the reactors' power is used to provide thrust instead). However they *DO* keep any speed they were allowed to spin up while on the runway. And KSP Interstellar Mod's electrical generators keep that speed for a VERY long time (perhaps even indefinitely). Even if they do slowly spin down, like a real-life generator, it's easy enough for me to wait on the runway until they are fully spun-up, and THEN liftoff. The generators are capable of converting the stored mechanical energy built up on the runway into electrical energy as needed in flight- and providing more than enough electricity to make it to orbit. Thus, I have a spaceplane that, if allowed to spin up its generators for a bit of time on the runway (it only takes them a few minutes to fully spin up), is more than capable of making it to orbit. However, I didn't fully realize the generators wouldn't spin up in-flight on my first flight, and so didn't think to wait for a spin-up cycle on the runway. As a result, I only made it to about 32,000 meters (with a steadily increasing rate of climb) before my plasma thrusters cut out unexpectedly on my first flight. I was able to pull out of the resultant tailspin I entered into (I didn't react fast enough to pull the nose back down closer to the horizon, and the plane stalled at about 36,000 meters and started falling like a rock), but I needed to land to let the generators spin back up and try this all again... It took nearly an hour for the plane to climb to its peak speed (a little over 465 m/s) at its maximum curising altitude (about 21,250 meters on Kerbin with turbojets only, 32% uranium, and a full fuel load of ArgonGas), so I haven't gotten in another full attempt yet. However the plane is spinning up on the runway as I speak (I reverted rather then go through the hassle of flying the rest of the way around Kerbin and landing the thing), so I should have a trip to Duna to report on relatively soon if all goes smoothly. By the way, one last note on the design, if anybody is looking to utilize the design or engineer a better version of the thing (I'll post the text for the craft file if anyone wants it)- this model DOES feature a radiator, unlike the Egret- but it is a very small one, too small to dissipate the heat quite as fast as it generates when both the electrical generators and reactors are running. This means that it IS theoretically possible to overheat the reactors on the ground if one somehow kept the generators running for a really long time (they stop generating WasteHeat as soon as they are fully spun up though, and the radiators give off more heat the hotter the craft gets- so it is very difficult and would probably take something like several DAYS or WEEKS of continuous operation- i.e. don't try to power a Science Lab on the ground performing research with the plane for a long period of time via a KAS which in docking mode- as the reactors will probably eventually just overheat and shutdown, leaving the lab unpowered- though the emergency auto-shutdown heat levels of 95% max normally cause no damage to the plane, you have to somehow heat it even further to 100% to create an explosion.) I know it's not much, and very technical, but I thought I'd start off by presenting the plane and some of its technical challenges and advantages, so my next post (on my actual trip to Duna with it) won't be nearly as long. I hope you guys enjoyed it nonetheless. Oh, and Sirine, *DON'T* reply to this thread- I don't have the patience for your antics tonight. Time to go now. The spaceplane finished a full spin-up cycle on 1x time while I was writing this post. Time to get that (space)plane to orbit. Regards, Northstar

Easier said than done. Some aircraft- particularly those with very large, multi-part, Albatross-like wings, as that one has, are incapable of withstanding the G's of a rocket trip up. That being said, I'm sure it can be done- if the part count doesn't kill the computer trying to run it first! That's basically my plan for bringing my planes to Duna. Speaking of which, at this point I need some input from others. I've developed four different models of thermal turbojet plane- all with very high altitude ceilings, and I need to decide which to try to bring to Duna first. In addition to the two models I presented before ('The Egret' and the fighter-plane like one, which I decided to name 'The Firefly'), I've now developed: 'The Eagle'- which is basically a stretched 3-wing version of the 'Egret', with a lighter (Mk1) fuselage, and 2 of the stock Mk2 Cockpits instead of 1 of the B9 Mk2's (more SAS force for the same mass and electricity consumption with the stock Mk2's- plus more usable length to attach wings). It has the highest altitude ceiling of all my designs- able to hold at about 32,800 meters on Kerbin. Its top speed is also the highest of all my designs- at 1,242 m/s near max altitude. It can also take off almost instantly on a flat surface (like the runway) on Kerbin- so it probably has a reasonable length takeoff roll on Duna too. And, 'The Egret 2'- which is basically a stretched version of the 'Egret', once again with 3 wings instead of 2- but a Mk2 fuselage and twin thermal turbojet engines instead of a single tubojet engine. It also has a slightly lower intake ratio, as it only has two additional 1.25 m intakes to feed its two engines- but it still is incapable of reaching a high enough height on Kerbin to stall (Duna might be another story though, due to the lower gravity). Surprisingly, the Egret doesn't seem to benefit from a higher top speed than the Egret: in fact, its top speed is slightly lower, at 1154 m/s instead of 1201 m/s- probably because of the heavy fueslage bicoupler for the engines (in KSP, drag is proportional to weight unless you have FAR installed- which institutes a more realistic, but much more CPU-intensive model based on cross-sectional area in the direction of movement). Nevertheless, it is a more powerful plane than any of my other models- and as such, might conceivably be able to haul more weight in cargo, say, if I swapped the 5 meter fuselage for a 5 meter fuel tank or 5 meter cargo bay (it has no use for fuel, so the fuel would be 'cargo'), or if I loaded extra uranium in the reactors. Its sustainable altitude ceiling is also higher than the Egret or Firefly- at about 31,250 meters on Kerbin, as well as its top speed (I never got a firm number on the Egret, but it was somewhere between 1000 m/s and 1100 m/s). Finally, it can also take off very quickly on a flat surface at Kerbin sea level- due to its high thrust and low wingload- but so can all my other designs except the Firefly (which barely makes it off the runway)- but doesn't land quite as slowly as the original Egret or Eagle: as much of that super-short takeoff is due to very rapid acceleration from its twin engines. Just to review the previous designs as well: The Firefly flies more quickly at the altitudes it *is* capable of reaching, due to its 3 engines and higher TWR than my other designs- and with high maneuverability and an altitude ceiling of 18,750 meters on Kerbin (that's about 6420 meters on Duna- similar to the D'OH, but much faster-flying at that altitude- reaching a top speed of 384 m/s at that height on Kerbin) it should still be able to navigate Duna successfully. Its greatest weakness is its very high wingload- which means it relies on two XL radial parachutes to touch down successfully, and has a moderate chance of lawn-darting if they fully deploy before touchdown (I cut them first on Kerbin- but that wouldn't technically be sustainable for long-term operations on Duna- one of the challenge requirements- even if I only did it in emergencies.) The Egret flies more slowly relative to its altitude than the Firefly, the Eagle, or the Egret 2. It has the second-lowest altitude ceiling of all my designs (about 27,500 meters), and the second slowest touchdown and liftoff speed (after the Eagle)- though all my designs except the Firefly can takeoff on very short cycles, they all touchdown at different speeds due to different reliance on lift vs their Thrust-Weight Ratio to liftoff. It is "handier" than all my designs though- at is is less long and stretched out, and looks like it could take more of a beating in a rough landing without losing parts. Summary: 'The Firefly': Long takeoff (even on Kerbin), highest speed relative to altitude, dangerous touchdown speed, altitude ceiling of 18,750 m, top speed of 384 m/s, lightest weight 'The Egret': Short takeoff on Kerbin, slowest speed relative to altitude, second-slowest touchdown, altitude ceiling of 29,500 m, top speed of 1200 m/s, medium-weight 'The Egret 2': Super-short takeoff, higher speed relative to altitude, second-fastest touchdown, altitude ceiling of 31,250m, top speed of 1154 m/s, medium-heavy weight 'The Eagle': Shortest takeoff, higher speed relative to altitude, slowest touchdown, altitude ceiling of 32,800 m, top speed of 1242 m/s, lightweight OTHER NOTES: - The Egret is the only design with no heat radiators. This is just one of the corners I cut on the design to save on weight (another is no parachutes- though none of my designs feature them except the Firefly). As such its nuclear reactor will overheat to the point of emergency shutdown when left inactive on the ground for too long- but can be manually reactivated after a bit of passive cooling by one of the pilots before takeoff, no harm done (this also technically greatly saves on the need for fuel reprocessing trips- as the reactor will only be operational when in the air, and there is no other way to shut it off besides allowing it to reach emergency overheat). Heat production is NOT a problem at all when the engine is running- as the very airflow that is used to generate the thrust also cools the engine- so there is absolutely no danger of the plane suddenly dropping out of the sky, unless it is allowed to enter an unpowered glide for too long- in which case the reactor WILL overheat. - The Egret and Firefly currently lack KAS attachment ports (the Eagle and Egret 2 have them). They can be slapped on the rocket before launch if necessary (I doubt it will change their performance much), or if this is allowed, manually attached and detached in the field- since the only time they need them is when they are getting their nuclear fuel reprocessed every once a game-year or so. If this is allowed under the challenge requirements, none of my designs would feature them- as it is far more efficient to just store an extra attachment port attached to the (stationary and safely landed) nuclear fuel reprocessing station, and reattach it to the nuclear turbojet whenever fuel reprocessing is needed, than it is to haul the (tiny bit of) extra weight, drag, and lag through the air on flight after flight when it's not actively needed. - The Eagle and Firefly's cockpits both have lower impact tolerance than those of the Egret and Egret 2. This somewhat reduces the chance of pilot survival during a crash-landing.

So far, fun challenge. Need to figure out how to get it to Duna in the first place. Might just take off the tail cones and slap on some jettison-able turbo-jets, or something. Good job! Now you just need to figure out how to get it to Duna in one piece!

Now that I have a substantial spacedock in orbit, and two spacecraft capable of running purely on LiquidFuel (my Nuclear Science Lab and the engine of my Orbital Spacedock- though the latter probably isn't going to be leaving Low Kerbin Orbit anytime soon- at least not until I construct a better LKO Spacedock entirely in orbit, not constrained by the need to make orbit from the Launchpad, and far less rationed in terms of vessel mass as a result... *THEN* I might send the existing spacedock somewhere I don't need as much fuel storage or construction capacity- like in orbit of the Mun or Minmus) and hopefully a functional Atmospheric Scooping Ship design that will allow me to stretch that LiquidFuel even further (a Thermal Rocket obtains twice the thrust, but only 75% the ISP, from using LFO mix instead of pure LiquidFuel. However given the more than doubling of overall fuel mass- LFO mix burns in a 9:11 ration of LiquidFuel to Oxidizer- you get over 50% more overall Delta-V if you collect Oxidizer in the field, and use LFO instead) I decided it was time to develop a new line of fuel tankers, designed to haul pure LiquidFuel to orbit without all that heavy Oxidizer... My previous "heavy" fuel tanker design was outdated, anyways- having been developed when the largest tanks I had available for its launch vehicle were half-height 3.75 meter tanks, and was only marginally upgraded since its development- to carry one full-length 3.75 meter tank instead of two half-length 3.75 meter tanks on the launch vehicle, after I developed the appropriate technology for full-length 3.75 meter tanks... I now had all the way up to Novapunch2's full-length 5 meter tanks available for my launch vehicles- so it was time to upgrade my heavy fuel tankers to versions with heavier payload stages, so I could carry more fuel to orbit in one launch, Oxidizer or not... These were the two main designs I tried for my new model of heavy fuel tanker. A key design criteria for any heavy tanker line I develop is the ability to carry its fuel a very long-range and perform efficient capture burns around other planets if necessary: so I utilized nuclear engines for the upper stages. One design featured 4 stock LV-N nuclear engines to carry the payload stage. It was designed to shed two of these once their fuel tanks were depleted- such as after a long capture burn from which no return trip was necessary: The other design featured two of Near Future Mod's twin-fusion nuclear engines- which feature slightly better thrust (75 instead of 60 kN), a smaller profile, and a better TWR- though they are heavier than LV-N's. It had lower overall thrust- but I decided I didn't really need 240 kN of thrust for a vessel of that size: 150 kN would do, and would save weight (and extend range) in the process... It still had four radial 1.25 meter LFO tanks- just two of them were drop tanks with no engines attached. Both designs made orbit, though the LV-N design did have a bit of trouble with the engines extending too close to the ascent stage decoupler in earlier versions- leading to a pair of the engines detaching prematurely (before circularization) in one of the final test flights. LV-N's also have the annoying tendency for the engines to overheat- and if allowed to run full-thrust in the upper atmosphere for too long, all four of them would explode simultaneously- leaving my tanker without thrust. This exact problem doomed one of my earlier test flights of the tanker design. As a side-note, LV-N's tend to be able to run indefinitely in vacuum, if there are a couple parts nearby to act as heat-sinks. Their overheating only a truly dangerous issue in the atmosphere, since the game simulates friction heat to a limited degree- but does nothing to simulate convective cooling. I settled on the twin-fusion design because of its reduced engine weight and thus superior efficiency, and the slightly reduced (though still very dangerous) tendency of the engines to overheat. I also considered creating an even lower-thrust design with just two LV-N's, for reasons of efficiency: but abandoned that line of designs because of how efficiently it required my ascent to be in order for the two LV-N's to still be able to reach a stable orbit (if I started my gravity turn a little too late, or too early, I could easily find myself unable to reach orbit. The twin-fusion design also could experience this issue- but with 25% more upper-stage thrust, it required a significantly more inefficient ascent.) I performed one successful launch of the final version of each design before making my decision. So now, I have two rather large LiquidFuel tankers in low Kerbin orbit. They're not the largest designs I could build, mind you (if lag were less of an issue for me, I might utilize four much taller 5-meter stacks tied to the "root" stack with XL girders and struts. I used to launch rockets like these with 2.5 meter stacks, back before I discovered the Novapunch2 pack: now I just use one 5-meter stack; which has the same effective cross-sectional area, less drag, and less lag) not even with a single 5-meter stack (the wonders of radial boosters for raising center of thrust: they allow much taller rockets). But the twin-fusion design I settled on is a very utilitarian and efficient design, with a VERY reasonable part-count once it dumps its boosters and ascent stage. In my typical efficiency-minded fashion, though, I did try one trick during the circularization of my twin-fusion design that cost me rather severely... I noticed during my test launches that my fuel tankers were reaching their circularization burns with a little bit of fuel still left in the ascent stage (though not enough to bring it to orbit as well). So, rather than leaving the fusion engines idle while coasting to my circularization burn, and simply burning the ascent stage dry and decoupling it, I tried to run the fusion engines on a *LOW* power level (running the upper-stage engines, even though they were radial, tended to very quickly overheat and explode the lower stage's 5 to 3.75 meter adapter- something I noticed during one of my early test flights of the design). However, after noticing that I could safely run the engines at about 20-25% thrust without any parts exploding, I decided to step it up to 35% thrust or so... This turned out to be a huge mistake: I ended up overheating the large fuel tank of the 5 meter stage by doing this- and the resultant explosion cost me the approximately 830 LiquidFuel (and corresponding amount of Oxidizer) still left in the tank... Since the last bit of fuel in a stage always is worth the most Delta-V, I was a little bit peeved with this (conversely, the first bit is worth the least- so I would end up burning a lot more impulse in upper-stage fuel to make up for the loss). Nonetheless, the tanker still reached a stable orbit easily enough, and should still be able to deliver its LiquidFuel payload to the Orbital Spacedock with plenty of LFO mix to spare (which I intend to drain into the Orbital Spacedock's LFO tanks- and recycle the tanker with my Scrapper Ship- having no more use for it at the moment.) Orbital rendezvous are horribly annoying to achieve, so I decided to save that for a later post (coming very soon)- but here's an image of my twin-fusion engine heavy fuel tanker in circular LKO: My plans for the future involve landing a KSP-Interstellar Science Lab on the Mun's surface to electrolyze Regolith (mainly for the oxidizer to mix with my liquid fuel- which it produces in a 4:1 ratio with aluminum- which also happens to be the ratio the mod's aluminum-oxidizer engines burn it at.) I'm not quite sure yet if I'll need to land an aluminum-oxide rocket or two on the surface to store the aluminum that is produces, or if I'll be able to run the electrolysis without anywhere to store the aluminum and just throw it out. Aluminum-Oxidizer engines are decent, and they perform better than other SolidFuel rockets- perhaps because they're a solid-liquid hybrid design- but they're still not nearly as efficient (ISP-wise) as liquid-fueled rockets (especially if I pump the LFO mix into one of my Nuclear Thermal Rocket Nozzles). What's more- and the main reason I don't wish to use them too much if I can avoid it- they only come in one, huge, unwieldy size (which I have a hard time fitting into the upper stages of my rockets). The mod hasn't even given them their own texture yet- their texture is basically just an upsized version of the ugly Route-10 boosters you start the game off with... So, while I *CAN* haul a few (empty) Aluminum-Oxidizer engines out to the Mun from Kerbin's surface- or more likely due to their high dry-mass weight will just make a couple empty ones out of recycled scrap metal in low Kerbin orbit (which is probably a lot more realistic than, say, making a huge solar array out of recycled used rockets that were mostly metal and only had a few small solar panels on them...) I probably won't. If I do, the only reason will probably be that it turns out I need aluminum storage space for my elecrolysis operations on the Mun to work- and even then I'll probably just periodically dump the aluminum with TAC Fuel Balancer (if it allows me to), and divert the oxidizer to LFO rockets... I also am going to test out that Atmospheric Scooping Ship pretty soon- some time after I refuel my Orbital Spacedock with enough LiquidFuel to fuel it, and deliver my Scrap Ship's load of RocketParts to it so I have something to build it out of... (And possibly, I might also send some additional Uranium Hexafluoride in a small throwaway reactor, since this is the only way to transport it. It turns out the Science Lab uses an "always active" flag to produce its gradual trickle of Science Points when set to research-mode, even when it is not the "Focus". However this also means it consumes UF6 to fuel its reactor even when not actively loaded as well. I've already had to reprocess the spacedock's UF6 supply once- since thanks to time-warping with my SensorSat from a couple posts back, it's been nearly two in-game months since I launched the thing with a less than 5% uranium load. Luckily, it appears the reprocessing is close to 100% efficient or actually is 100% efficient, because I didn't notice any significant reduction in my total UF6 levels compared to launch after the reprocessing was complete...) Last, but not least, here are a couple nice pictures of my Mun Rover and my Eve Probe (when landed on Gilly) viewing their respective sunsets I took a while back and uploaded on one of my other threads. I'd like to leave you guys with something nice to look at...

I kept the SAS off during descent, as I found it locked my heading too strongly while still above the surface. I actually turned it on just a few seconds before touching down to attempt to lock my heading ("nose" straight up)- it just apparently wasn't strong enough to prevent a flop from the tiny weight-imbalance.

With a little luck in my Minmus escape, my probe landed on a trajectory that slingshots it around Kerbin, into another slingshot with the Mun where it picks up more speed, and then on an escape trajectory out of the Kerbin system. So rather than trying to recover it on Kerbin with a powered descent- which seems unlikely to succeed at best, and was never really part of the original plan for the probe (it was equipped with no parachutes- and was intended to eventually be left deactivated in an out-of-the way orbit somewhere or on an extra-atmospheric moon's surface- probably eventually to see its recycling as scrap through use of a Scrap Ship like the one I presented earlier- or by a rover variant if on a moon surface), I decided to leave it on its current trajectory. It still has quite a bit of its final-stage fuel left (25.72/36.00 to be exact), and given its very low mass that equates to quite a bit of Delta-V: though probably not nearly enough to reach even Duna or Eve. Plus, I don't have magnetospheric data on a high Kerbol orbit yet (what I should get once exiting Kerbin's SOI)- so its one-way trip out of the Kerbin system won't be in vain. Since I know this forum is all about pictures, here's one last cool pic of the probe I'm leaving you guys with to remember it by. Damaged and limping out of the Kerbin system- but immensely scientifically useful while it lasted- that's one tough little probe my Kerbals will probably be adding to their history books.

Thanks for the compliments, I really appreciate it. I totally understand the simulator logic- but there's also so much that's hard to simulate before it's ever been done. How can you really know how well a plane will take off or land on Mars (*cough*, I mean Duna) without knowing things like the precise coefficient of friction of the soil at the landing site, for instance? I see it as more or a challenge to go without simulators. IF something goes wrong, I see it as a challenge to try and fix it (like in my Mission Report thread- where already, I managed to strand two Kerbals in orbit in a spaceplane, and had to emergency EVA them to other ships in orbit- one more than 100 km away at the time the EVA was started). Now, that said, I'm generally not above F5/F9 when it comes to doing something stupid by accident, like staging a rocket when I didn't mean to; and I *WILL* revert a rocket as many times as necessary if it can't make it to orbit and survival looks unlikely, since I figure that any real space program would at least be equipped with some wind tunnels and aerospace engineers who understood all the calculations and mathematics behind designing a rocket that can actually fly- plus recovering all the debris is a pain sometimes. I'll even terminate debris to save on FPS and prevent collisions (a real space program could track debris, and has collision avoidance systems- much like hugely more advanced versions of what you see in some modern cars- to help detect and prevent such collisions)- though I've designed a Scrapper/Recycler ship to cut down on that in my ongoing Career Mode save (actually my only save at the moment). But, like you applauded, HyperEdit is where I draw the line. I totally understand if you do it, but I just can't bring myself around to it. Anyways, the D'OH was a very impressive (and utilitarian) aircraft, and I applaud you on it (as well as the guy who one-up'ed it recently). So I guess some great things do nonetheless come of HyperEdit at times... Regards, Northstar

OK, so my probe's visit to Minmus (and landing on it) turned out to be a little bumpy, to say the least. I thought that, as experienced a player as I am, having sent probes to Duna, Eve, the Mun, and Minmus many times before; I had this down pat. Apparently I forgot that even on the simplest of missions, something can always go wrong... First of all, here are some nice screenshots from my approach: After getting in nice and close- and transmitting a bunch of data about the (lack of a) magnetosphere from high and low orbit, I proceeded to bring my probe in to a *VERY* low orbit for a final landing insertion (which was never designed for landing, but I took a risk- because what's the worst that can happen on a moon as low-gravity as Minmus?). It went fairly smoothly, and I caught some BEAUTIFUL vistas while passing through a valley in the mountains/plateaus- the screenshots don't do it justice. Then, my probe came in on its final landing approach: Landing on Minmus with a TWR this high is always a little tricky, because the vessel tends to overthrust and bounce up and down when trying to cancel out the last few m/s of velocity, and this landing was no different. But what really caught the cake was what happened AFTER the probe had already safely touched down on the level, with absolutely no horizontal speed. See for yourself: Now normally, when this kind of thing happens to me on a moon like Minmus or Gilly, it's not a problem- because I always seem to have enough SAS force to tip the thing back up on its own. For that matter, I usually have enough to stop it form tipping in the first place. However, in designing this probe I was a little sloppy- and the antennae isn't perfectly centered. As a result, that tiny bit of off-center gravity seemed to completely disable my probe's ability to tip upright (trust me, I've tipped back much heavier vessels with the same probe core when they were perfectly balanced), probably thanks to the lovely quirks of the game's physics engine... Anyways, I was still able to get plenty of transmissions on the gravity from the surface, which is what I came for (previous missions had only collected Crew Reports, EVA reports, surface samples, temperature scans, and seismic data.) However, simulations back at Mission Control (F5/F9 runs) revealed that there was a high chance of the probe exploding into a million tiny bits if I attempted to use its engines to help it right itself- but I was out of other options, so I tried it anyways. The result was a headlong spin, and an impact with the ground before I was able to get it back under control (though maybe if I had been less busy snapping screenshots and more busy hawking the Navball I might have avoided that second impact.) Fortunately, I WAS able to bring the probe back under control. Here it is sailing away from the mess: As you can see, I lost a couple of the probe's solar panels, as well as one of the two magnetometers (in an uncanny bit of prescience I equipped two- for redundancy as well as to make it easier to produce symmetry.) I also burned quite a bit more fuel than I expected in the whole mess- thanks in large part to fuel wasted trying to control the spin. You can see the lower of the two stages I brought to Minmus lying there on the ground in the screenshot right after the impact flight log if you look very closely... The probe is still fully functional minus a balanced Center of Mass (thanks to the loss of the two solar panels and magnetometer on the side of the impact), but on its final stage of fuel. I'm really not sure what to do with the thing at this point- though I guess I might try aerocapture on Kerbin to see if I can get any Science from the recovered probe core (for "vessel recovered from the surface of Minmus"- since I don't think I've exhausted that one yet...) I'll update this post once I know how that goes...

My SensorSat approaches the Mun And after a capture burn, performs a burn to simultaneously cancel much of its remaining East/West momentum and move into a polar orbit at periapsis. After several orbits, and reading the magnetosphere strengths both at high and low orbit (I'm afraid neither has very strong magnetic readings around the Mun) for Science points, I capture the image seen here at the end of a very large transmission on the gravity readings (read: spam-series of gravity scans) over a crater I'd never captured high-orbit readings on before. I also capture several other readings like it over craters and biomes I'd never captured similar-altitude readings on before- loads of new scientific data for my Kerbals back home. And then, after snapping quite a few more screenshots... ] Head off towards Minmus... Sorry that was a rather bland post guys and gals. I know a lot of you think of the Mun as nothing more than a barren gray rock. But personally, I still find it all exciting- after all, it's space exploration! I'll have another post soon on my probe's visit to Minmus (shouldn't be nearly as long- there isn't much to see there. Though, I'll probably try landing the probe on Minmus since my probe has enough fuel and TWR, and the low gravity and flat "lakebeds" should make it fairly easy...) After that, I've got some ambitious plans- including the redeployment of my Nuclear Science Lab to Mun or Minmus orbit, the movement of my old fuel depot to one of these orbits as well, the construction and testing of my atmospheric scooping ship, and the establishment of electrolysis operations on the Mun (KSP Interstellar allows you to electrolyze Regolith into Aluminum and Oxidizer, which can be used for aluminum-fueled rockets, or just for the Oxidizer...) By the way, some of you might have noticed that my sensor probe has four solar panels deployed in some pictures, but only two in others. No, that wasn't because I was smashing the action group buttons by accident or somesuch- that was intentional, and because KSP Interstellar adds a heat-management mechanism to all your rockets. Essentially, many electrical systems (especially solar panels and nuclear reactors) produce excess heat when they run (simulated by the WasteHeat resource). If too much of this heat is allowed to accumulate, it can damage the equipment (KSP Interstellar simulates this by causing parts to explode if the heat levels climb high enough). In the vacuum of space, this heat doesn't convect away from the surface of a rocket, so it just tends to accumulate- and its management is a serious challenge for any space program. KSP Interstellar's simulation of this mechanism is just one way it makes the game a little more realistic- and balances out the utility of some of its parts a little with extra challenge in other parts of the game. I'm really falling in love with that mod... KSP Interstellar allows you to manage this heat in a variety of ways- one of them is by use of heat radiator parts specifically designed to dissipate heat. Another is to simply control and limit its generation, since spacecraft still have a certain base level of heat dissipation that occurs even without specialized equipment to manage it- which in KSP is proportional to the vessel's mass (in real life, it is proportional to exposed surface area). Unlike in real life, vessels don't seem to give off more heat as they get hotter- so there isn't a realistic self-limiting effect on the temperatures a vessel can reach. So, as my probe's solar panels generate slightly more WasteHeat than my probe can dissipate, I was closing two to three of the solar panels whenever the batteries were fully charged and the power wasn't needed for a data transmission.

EEK! Look's like I'd been calculating altitudes on Duna all with the wrong Scale Height! The correct figure is 3000 meters, not 5000 meters! (that's the scale height for Kerbin) Given this revelation, the new (re-calculated) maximum cruising altitude for the Egret on Duna is actually 12,870 meters before taking into account the lower gravity- not 13,000 meters. I got lucky on this one, because it just so happened that the two slopes intersect very near this point- otherwise I would have calculated a number that was really far off before, and looked like even more of a fool right now. I'll update the calculation section in my earlier post to reflect the new numbers- otherwise people might end up using these numbers themselves, and abandoning perfectly good designs because they didn't think they could fly high enough, or alternatively, building planes that they think can fly on Duna- but just end up smashing into the ground. EDIT: Oh, one last thing. IF this version of Thermal Turbojet works well on Duna, I'll be building an even higher-altitude version using a 2.5 meter fuselage. I can't do this just now because I haven't yet discovered the tech node for the super-giant sized B9 wings; but once I develop this tech tree node, I'll be designing a Duna Heavy Lifter using a Thermal Turbojet. As it just so happens, the 2.5 meter reactor is a little less than 6 times heavier than the 1.25 meter variant, but produces a thrust approximately 10 times as powerful as 1.25 meter with a Thermal Rocket Nozzle. Assuming the same ratios hold true for a Thermal Turbojet, I can expect a much higher altitude ceiling with a 2.5 meter reactor and Thermal Turbojet- assuming I can bring the wingload low enough. If not, I'll just slap on 2-4 of the 1.25 reactor-turbojet pairs to a 2.5 meter version (probably on the wings, though maybe also on the rear) and still obtain a probably moderately higher altitude ceiling than the Egret. The 2.5 meter design I speak of would be more of of a C-130 style heavy lifter than a medium-heavy scout plane like the Egret, however- so I don't expect it to land or takeoff on a dime (the wingload would be much heavier- relying more on speed for lift). Instead, it would be more useful for lifting heavy cargo loads from one permanent Duna base to another (assisted greatly by selection of flat sites, and placement of Extraterrestrial Launchpads Mod deployable runways- which are insanely heavy, and wouldn't be the very first things I bring to Duna- of course.) Getting something that heavy and with that much lift to Kerbin orbit would also be challenging- I'd probably assemble it in-orbit or on Duna herself (with Extraterrestrial Launchpads infrastructure) rather than on Kerbin, since by that point the Egret (or a modified version thereof) would already have met this challenge's requirements. Probably most useful for hauling Kethane to a central refinery (since it'd be a Nuclear Thermal Turbojet, it wouldn't burn any of the Kethane it'd be transporting), once they release a version of the Kethane Pack that's Career Mode compatible... It could also be useful for Extraterrestial Launchpads mod "Ore"- which requires the Kethane Pack to work- as it utilizes Kethane Pack's resource placement and mining code for Ore (with permission, of course.)