Archgeek

True enough, and I'll let a lot of things slip on by when someone just doesn't know about them, as I cannot be angry at that, only sad; but willfully ignoring key information and failing to apply information just learned? Therein lies the difference between ignorance and stupidity, newbs and n00bz. That sort of behaviour makes me want to put liquid tungsten next to something they cherish. (Note that I'm going off the searing memory of that awful FTL run and have not seen the KSP video.)

While doing some more nuke testing, I may've accidentally made a bit of a Good for about 101 tonnes to 6km/s at a pathetic TWR

Heh, in OP's defense, I've never seen nerd^3 not suck at something. I wanted to manifest flames in his lungs watching his FTL let's play. He. Did. Not. Pause. You can only get away with that if you don't suck. He...did not have that condition in place.

Welp, looks like I did indeed misunderstand the fuel flow numbers. I started in on some testing, getting no less than six data points in .90, both with delta-v and burn time, as well as clocking fuel flow at .69 LF and .84 O per second each, and before I could set in on comparing KE and practical delta-v in 1.02, I saw that the fuel flow is now the sum of those, 1.53/s, more than double what I expected. So yeah, that's actually a pretty big nerf. Edit: well dang, the sleepwalker up there beat me to it. Holy crap that thing looks awesome. It's like Dynasoar writ large.

Unless I didn't read the fuel flow-numbers right, the engine should burn through the same tank without oxidiser in the same time as it once burned through both. Thrust is still 60kN, and 60kN for the same time as before but without the mass of the oxidiser that was can only result in more delta-v. Sure, theoretically the rocket equation would state that higher wet mass with the same dry mass should give more delta-v (actually less dry mass because the engine was lighter then), but due to the way the game works (accelerating dynamically by thrust over current mass times time while mass changes) the oxidizer didn't really "count" as propellant. If one were to compare the working delta-v of nuclear craft in both .90 and 1.02, they'd find a crossover point where the new engine did better, once the lack of oxidiser mass overcame the added engine mass. Though thinking about it...this may've screwed with mechjeb and KE's calculations.

You know, I can't help but notice that the thrust is still 60kN, and the fuel flow unchanged from the old vacuum minimum of 1.53/s. As a result it goes through an LF-O tank in the same time it used to go through an LF+O tank. If anything, that's a buff, since we don't have to take that oxidizer upstairs! It's tempered by the extra .75 tonnes of engine we have now, but it still severely undermines people's standing. What's worse, if you're taking spaceplane parts up for dedicated nukeage, you're looking at let's say 2 mk1 fuselages over an FL-T800 tank, getting 300 LF with a dry mass of .3 for the fuselages, over 360 with a .5 dry mass for the FL-T800. Or if you're cool, you use mk2 short tanks instead, getting 400 LF with a .29 dry mass, beating the FL-T800 for both fuel and mass. I guess persons are complaining that they cannot abuse that as much as they'd like?

Wow, was that 1.0 or or 1.0.2? Here's my incomplete data on 1.0.2: Re-entry mk1 tests: 76km x 20km : max temp under 500k 76km x -400m: max temp under 411k 160km x 20km: max temp 430k 950km x 20km: max temp 464k 1000km x 20.2km: max temp 470k 950.6km x 1.8km: max temp 472k Mun to 0km: SOON Re-entry mk2 tests: 100km x 20km: max temp 434.4k 1000km x 20km: max temp 228.0k 996km x -495km: max temp 457.8k Minmus to Kerbin tests: SOON

Was that with or without a heat shield? Judging from the flipping issue, I'm guessing it was with. How much ablator did you go through on a descent? Without, you may've had a harder time. In 1.0.2 hardly any is used, and even an unprotected pod barely gets warm.

Here's my test rig: and mostly empty I've got the panels on a tank between the two big heat sources, so it should cool reasonably well. It's launched with just a bit more than enough delta-v on board to get down to Minmus's surface and start drilling, and is intended to test things like the power draw of the drills and refinery, the heating and efficiency curve of them both with Bill on board and out stretching his legs, and how many fuel cells are needed to drill or refine through the night. The whole thing's designed to fill itself up on propellants with minimal ore storage, then fill the ore can up because why not, and drag everything up to an orbital fuel depot and process the ore while it's transferring the pre-made fuels. A serious production design will probably have a few LF-only tanks, or possibly a big mk3 tank, since the bulk of craft gassing up will probably be interplanetary NERVA ships. Efficiency data forthcoming a soon as it gets to work.

Well there's your problem -- you should have your fuel depot out at Minmus. Just launch or construct your interplanetary vessels with only 800 to 1km/s delta-v on board for the trip to the Minmus gas station, either dock with the depot itself or an intermediary tanker depending on your style, load up on what you need, abuse Minmus or the Mun for a free inclination change and/or gravity slingshot to make up for the lost near-kerbin Oberth effect, and enjoy the savings in lifter cost and amusingly short transfer burn times for the low low price of a more interesting mission profile plus upkeep of the fuel depot and mining operation, no silly dragging of a heavy tanker up and down Kerbin's gravity well required.

I'm pretty sure this effect is a least partly legit. The night of the 1.0 release I took an Aeris...4? The one with the the LV-T45 on it upstairs, ran out of gas and electric charge, which is beside the point, and got it back down using just its RCS, which I also used to take a nearly 90 degree angle of attack very very high up, easing up a bit once the atmosphere showed up noticabably to try and deflect upward some to stay higher longer, since I was downright terrified of trying to get down an unshielded space plane. This resulted in enough gradual slow down that I barely saw any re-entry flare, though it did take a while. Note that this was in the 1.0 un-soup.

But what if one's mother taught them orbital mechanics?

'Saw shadows of it on xkcd, then encountered a youtube video for a "you will not go to space today challenge", wherein all craft had to start facing the wrong way. 'Turned out it was one of Scott Manley's videos. I avoided the game like the plague after that, sensing a very dangerous timesink and being more focused on finishing my last few months of college. I did however catch a few of the "Rocket Science is Hard" videos, by the likes of Danny and SWDennis, increasing my interest in the game. I think I bought the game after graduation in .18 during a steam sale, and guided by Scott like so many, have been playing ever since, though mostly creating monstrosities and experimental craft -- I've somehow never finished a tech tree or been anywhere other than the Kerbin system, Duna, Laythe, Eve/Gilly, or the sun.

It's also rocket gimbals being all-or-nothing. I did a mun injection for a re-entry test, lazily hitting hold prograde on an OCTO-2, and stared bemused at the remainder of my LV-T45 lift stage flipping out in each available direction for a second before it emptied.

Eh, that was super easy to ignore. One just chose to not open chutes until doing so was reasonable. What troubles this thread is how a change other than the parachute fix neutered the ability of the atmosphere to melt an unprotected command pod.

Indeed, and considering how easily something can be made asymptotically thermo-stable, that makes it all the safer to forego radatiative fins and friends and just let heatsinking do the work for most reasonable burn times. HEH , by infinite fuel, I mean running the tank from full to empty, then turning on infinite fuel, in order to test worst-case heating. I have several "nuke test" craft on various terrifying and/or very​ hyperbolic trajectories in my sandbox save from this Thomas Foolery.

Yeah, I've just been testing bare pods with top-mounted chutes. Exposed bits and bobs will still blow if you don't pull them up high enough to be occluded by the pod's base. Also for some reason, kerbals in lawn chairs on heat shields will take convection flux like they're dangling out the side while everything near them is untouched. In 1.0, you see, a bare pod couldn't easily make it down inact, and you were likely to use half of the ablator on a shield. Losing chutes is minor in comparison, unless you're in career and there are kerbals on board.

Actually, there's a rather visible shadow shield in the LV-N model already. You can see it right above the reactor bit. Indeed! Additional testing is needed to ensure the central tank and KR-L2 aren't key to the design, but an old hybrid drive stage with 6 LV-Ns on radial mk2 LF tanks has proven to work a treat, to the point that it asymptoically cannot overheat under infinite fuel, due to the conduction and rad fluxes approaching one another with hundreds of Kelvin to spare. In fact the trick may largely be to just put a larger tank on each, since radiation is affected by the pre-calculated surface area of a part's mesh. If your craft needs solar panels anyway, I've also found that even the mk1 LF tanks are impervious under infinite fuel with the help of either 2 gigantors or 8 mid-size panels.

Just what were the re-entry heat settings for 1.0? I've been messing around with a minimalistic test rig and the worst I've been able to do to a mk1 pod was 472k coming down from a 950.6km x 1.8km orbit, and just under 411k from a 76km x -400m orbit. Sadly, 1.02 happened when I was at work so I didn't get a chance to save a 1.0 copy and so lack a reference to the old config, and I miss having setting my ablator being part of the design considerations for a mission. EDIT: I see it's even worse than I thought -- an unshielded mk2 pod coming down from a 1000km x 20km orbit only pulled a max temp of 228.0k... 'turns out the heating's weak enough that starting temperature has a greater effect. Even rampaging down from 1000 x -495km only got a max temp of 457.8k.

Heheh, no need to turn down the thrust. My tests have shown that it's not all that hard to get something that'll never get hot enough to blow anything up, due to logarithmic heating and cooling curves. This modified drive assembly was run from MET 5:00 to 50:00, and was forced to run to there after running out of fuel at around 10:30. Everything's nearly in perfect balance with hundreds of kelvins to spare. The rhino's on board as an escape kicker motor from the drive's original design as an Eve transfer stage, but it serves as an oddly good radiator once out of oxidizer. It's not obvious from the picture, but the conduction and radiation flux numbers have been converging, such that nothing other than the NERVAs are going to even hit 1800 kelvin. The key seems to be either using an immediate tank a size larger than the LV-N, or to apply radiating fins. A simpler experiment not pictured showed that a single NERVA cannot blow up a single mk1 fuselage if it has two gigantors or eight of the midsize extendable panels attached. Six might also work. Things may look hairy, but the hotter things get, the faster they cool.

Have you tried one half-size Kerbodyne tank, partially drained of oxidizer and with a Rhino engine on the back of it, flanked by six stacks of two mk1 LF tanks with a NERVA? The rhino and oxidizer can be used to boost TWR when needed, and when off makes a disturbingly effective radiator of the heat flowing into the central tank from the radial ones. Testing showed flux numbers of over 50k (and this was in 1.0 when things were running dang hot). In 1.02 the assembly runs out of gas first, often sun-diving or going out past Eeloo or hyperbolically away from Kerbol.

Just watch out for the mun on the way out and back. It likes to interfere. Though you may be able to use it to cheapen the manuvre further.

Now that's not entirely true -- just after release I dorked around with the stock planes a bunch, and managed to get the LVT-45 having one upstairs, then back down in one piece via holding a very high angle of attack to hit what atmosphere there was like a sail. If there had been no drag up there, Jeb wouldn't've made it back down, much less landed up a slope on some sand dunes. Also, I've never had a heat-shield fail me, and have developed the habit of turning the ablator down to save mass. The 1.02 settings have made even that bit kinda superfluous. (They do however, fail exposed kerbals in lawn chairs -- massive convection flux that only the kerbal feels. 'Not sure what's up with that.) Further, I miss my near-perfect gravity turns I was getting in 1.0 -- I'd derp over slightly at launch, kill SAS, and watch it steadilly droop 'till my apo was where I wanted, and looking at the map I was already half-circularized. Now my fins provide too much restoring force and my rotation just stops. Though you're quite right, people have been freaking out way too much over each change.

Aren't OX-STATs still physicsless, giving them a power/mass ratio of infinity, thus limiting them mainly by surface area and part count?

For my part I found out an inactive KR-2L makes for quite the radiator. I tested a slightly modified transfer stage for a previous Eve lander with a central half kerbodyne tank with a KR-2L flanked by six FL-T800s with nukes on 'em, set up to pull fuel into the nukes from the center so as to get the most delta-v out of it with an option to boost thrust if needed, with around 5:40 burn time in it, and managed 4 minutes 10 seconds at full throttle before stopping to prevent FL-T explosion. over -22 thousand rad flux...'pretty sure this thing is keeping the rest of the ship alive at this point. The nukes themselves were only radiating around 8k. Note that the tank is only radiating 6.2k or so. nearly 31k rad flux. In a previous un-screenshotted test, I ran it to destruction, pulling off a burn that wound up past Eeloo. That big engine bell turns out to make for quite the heat sink.