capi3101

I find that if the target is about 450,000 m downrange when I launch, I usually close to a rendezvous within an orbit or two. You usually want that much to kill any difference in declination anyway (that's if you're doing it with just RCS; LOX you can get it in one go usually if you're careful about it). While I'm at it, add RCS if you haven't got it already; assuming you're attempting to rendezvous with LOX you could use it as a backup when your tanks run dry.

Tried to build my first skycrane last night for the Hellrider 7. Might've even gotten into orbit had the last asparagus stage not been clipped into the support truss for the payload. At least no one was aboard... Got the Damnation 7 up to 9300 m/s of delta-V last night; stuck a Zenith Supernova on the bottom of it and had close to 13,000 delta-V overall. Now if I can just figure out a) how to launch that into Kerbin orbit while leaving all the stages intact and how to keep the "payload" from decoupling prematurely, I might have a working Eve lander. I suppose I'll ultimately have to consider c) how to put ladders down the center stack and d) putting enough lander legs and chutes to bring the whole thing down safely as well. Then there's e) replacing some of those payload engines with some that have enough thrust to put the Evil TWR over 1.0...

Are you launching that straight from Kerbin? Be advised that LV-Ns are lousy launch stage engines - they don't get their awesome Isp until you hit space. Rockets without some kind of central engine have a tendency to spin due to leverage. Unless you absolutely absolutely have to have it exactly that way, I'd advise you to put an engine on the bottom of that 32 tank. Preferably something with good steering authority like an LV-T45 or maybe even a Skipper. Winglets too.

1) I'd look at the Historical Mission Tutorials on the wiki. If nothing else, they'll give you good ideas for getting started. There is some other information there that may or may not be helpful...the Basic Rocket Design tutorial is how I got started. 2) I'd highly recommend flying with the navball, as others have suggested. If you need help with that, ask. 3) After the Mun? Minmus is a good way to learn how to hit a target that's not on the same orbital plane. It's an easier landing and it takes less delta-V to get there and back than it does from Mun, so you can use the same designs. After that, it's whatever you want to do. Me, I farted around with probe designs, then building boosters that didn't leave debris all over the place, and then I started sending missions to Duna/Ike and later to Eve/Gilly.

Only reason why escape wouldn't work that I could think of is if your ship is throttled up; hit X first and see if that has any effect.

When you set the other ship as the target in the map mode, you should see one or two sets of chevrons appear on the orbital path of your craft. These are your "intercept" points, the points where the orbits of the source and target crafts cross one another. They'll also tell you what the distance between the two craft will be at those points. Your job is to get that value down...within 1.0 km if you're just doing a rendezvous, all the way to zero if you're going to try to dock. You should also see two markers labeled "An" and "Dn". These are the ascending and descending nodes, respectively; when your reach the ascending node, your craft's orbit will begin travelling northward of the target's and vice versa. For a successful rendezvous, you want this to be zero in all cases - and you'd prefer it to say "NaN", which means "Not Applicable Node" (I think), which means your orbits are aligned spot on. So here's how you get to a rendezvous: 1) Note the locations and altitudes of the target's apoapsis and periapsis. When you launch the source craft, you're going to want your source craft's orbit to have as close to the same apopasis/periapsis altitudes/positions as you can manage. I find that waiting until the target is about 450,000m uprange of KSC helps, but you can play around with that value. 2) Launch and get into orbit. 3) Evaluate how well you did. Start with the ascending/descending nodes. If the value isn't zero, you're going to have to adjust the inclination of your orbit. Assuming you've launched eastward (heading 090) like all good Kerbonauts should, you want to aim southward on the horizon if you'll come up on the ascending node first and northward if the descending node is coming up first. 4) When you reach the node, perform a slow burn (unless you've really botched the launch and have a node of 15 degrees or more, then floor it). Get the value as close to 0.0 as you can. If the node starts pulling well away from your ship, stop the burn - if you're still not at zero at that point, try again later. 5) Meantime, when you come up to your first apsis, aim prograde and make a slow burn, and watch the effect it has on the intersects. If the value increases, stop, turn around and burn. Keep burning until the distance starts going back up again. 6) Keep doing this when you hit the nodes and apses. Eventually you'll figure out which way you need to adjust your orbits to bring the value down. Bear in mind that as long as the distance between the two craft is narrowing on its own, you don't necessarily have to do this every time you reach one of these points. 7) If you get close enough to the target, your game may automatically switch you over to "Target" mode on your velocity display. Unless you've got a close rendezvous on your intercepts, I'd manually switch it back over to "Orbit" mode. You can go back to Target mode once things are getting close. 8) Once you've got a close pass - within a kilometer, preferably within 0.5 kilometers, switch over to Target mode. Your gauge will now display your craft's velocity relative to the target. You want this to be roughly 1 meter per second per 100 meters range to the target; if you're travelling faster than that, aim retrograde and make a slow burn. 9) When you've closed to 2250m, you may notice the game shutter ever so slightly depending on your machine; that's the physics engine picking up the other craft. 10) I've already written up something on how to do the final docking today, if you need that. Here's the link. Good luck; let us know how things turn out.

Make sure if you go this route that you're using a manned control pod (i.e. one with a lot of torque available). I've tried the single RCS quad along the center of mass with an unmanned craft before; handled like Elsie the Cow...

V-key...C puts you in IVA mode.

Here are the basics, doesn't matter if you're using LOX thrust or RCS. 1) Make sure the velocity gauge over the navball is set to "Target". If it isn't, you can switch to docking mode or just click it until it comes up. 2) Watch the distance between you and the target; easiest way I find to do this is with the map but the data will come up in the flight view as long as you've got your target selected. 3) If the distance starts to creep back up, aim your ship at the retrograde marker (the yellow one with an x in the center) and reduce your relative velocity to zero m/s. 4) Once your relative speed is zeroed, aim at the target (the purple doughnut with a meatball in the center). Thrust ahead - ten meters per second should be sufficient if you're more than a thousand meters out. You should notice the distance dropping again. 5) Repeat as necessary. Slow your relative velocity as the distance closes - a good rule of thumb is 1 m/s for every 100 meters or so. 6) At 100 meters, slow to zero, adjust your aim and thrust towards the target. If you're aiming for a specific docking port on the target, this would be a good time to target it. 7) At 50 meters, slow to zero, adjust your aim and thrust towards the target. 8) At 20 meters, slow to zero and adjust your aim. Here's where you need to make sure you're aligned for docking. Easiest way to do this is to switch over to the second craft, target the first craft, and aim the second craft towards the first. If you haven't got a lot of torque or its turning response is crappy, it helps to timewarp for an ever so short amount of time once it's aligned. 9) Switch back to the first craft, adjust your aim again and thrust towards the target. 10) At 10 meters, slow to zero, adjust your aim carefully and thrust towards the target. No faster than 0.5 m/s at this pont; 0.3 is probably optimal. 11) At 5 meters, slow to zero, adjust your aim carefully and thrust towards the target. 12) Once the ports get within a meter or so of each other, they'll try and pull each other in. If your alignment isn't spot on, the two craft may dance around a bit; don't panic, just wait. Let us know how it turns out.

Delta-V is the name of the game (or at least it would be if KSP didn't sound cooler or at least like the name of a fried chicken chain). You need on average 4,550 m/s of available delta-V just to reach a 100k orbit. How much fuel that equates to is going to depend on a) the mass of your payload and the specific impulse of your engines. And the equation you use - the Tsiokolvsky Rocket Equation - has got one of those nasty-looking natural logarithms in it. It goes like this: delta-V = ln(M/Md) * 9.81 m/s^2 * Isp, where: M = total mass of the rocket Md = dry mass of the rocket (your rocket's mass after its fuel tanks are empty) Isp = Specific Impulse. When I plan missions, I usually assume the 1 atmosphere specific impulse of my rockets (i.e. when they are least efficient). Isp will increase as you enter space (i.e. your rockets will become more efficient), so it helps to use this planning value. On average, liquid fuel rockets in KSP have an Isp of about 290s on the ground (some more, some less, some a good deal more or less). Plug that figure into the equation and solve it for 4,550 m/s, and it turns out you want your mass ratio to be about 5:1. So figure out the mass of what you want to put into orbit (easiest way to do this stock is to just put the payload out on the launch pad without any booster elements, switch over to the map view and call up the info window) and then plan to put about five times as much mass into the booster. Bear in mind that only fuel tanks are going to affect that 5:1 ratio. Kerbal Engineer Redux (KER) or Mechjeb will do all the math for you if you're into mods. Me, I still prefer to do the calculation by hand (even though I've installed KER and have found it to be a useful tool).

A good gravity turn is also essential. Go to 45 degrees on a 090 heading when you get up to about 10,000 m, and then lower that to around 20 degrees on the same heading when you get to around 25,000 m and see if that helps any. You might also try shooting for a higher initial orbit around Kerbin, say 150 km or so (this is one of those counter-intuitive things...a higher orbit has a lower orbital velocity requirement and therefore requires less delta-V overall. The booster stage of the Kerbal X has about 4330 delta-V available by stupid_chris's pic on the first page of this thread; that's a little less than what's required for a 150k orbit).

I dock on RCS only regularly and find it easier to just leave the controls in Staging Mode. Only time I use translation is when I'm getting close to docking and my alignment isn't exactly perfect, and even then I'm liable just to use the IJKL keys. There are folks who suggest that in addition to four on each end, there should be four in the center aligned with the center of mass (I'm one of these folks, incidentally). Those center ones would be used to assist in translation only; one of those instances where the unidirectional block could be employed. Of course, if you use the standard blocks, that's extra thrust for prograde/retrograde maneuvers (and I find that helpful). Here's an example of something built in orbit; there are four distinct pieces here, each one has RCS thrusters fore, aft and in the centerline: Balanced thrusters aren't required for RCS docking maneuvers, but it does make things go a lot easier. So does having a command pod with good torque (so you're not totally reliant on RCS for rotation; it tends to throw things off a little when you're in close). Not sure if "chase cam" is an official thing or not (and if it is I'd like to know how to access it). Basically, you just position your camera behind the craft you're controlling. Personally, I like to move it over to the side when I get really close (~3-5 m) for the final docking maneuver.

I too attempted to use the stock Kerbal X to reach the Mun once. Whole reason why I have the Mun rescue cross on my salad bar... Of course, most of the stock craft can't really do any of the things advertised in their default configuration. I think that's the point - they're there to give you ideas for your own designs and to fart around with. Take the X for example - if you take the booster off the lander portion and add another stage (say an X200-8 and an LV-N), that oughta give you enough extra delta-V to make it into orbit without burning any of the lander's fuel. Possibly enough to transfer to the Mun without using fuel either. Granted, I haven't actually tried this. I should; if it doesn't work, it'd give me an excuse to deploy the Flying Dutchman 7 (my Munar rescue boat) again.

It may be that you're using too much fuel for landing. Can you talk us through how you perform a landing sequence typically? I find that with the basic little Scott Manley Minmus rocket lander (i.e. a 4 tonne module consisting of a Mk1 Command Pod with one chute, a stack decoupler, an FL-T400 tank, LV-909 engine, four lander legs and a ladder), you'll make it back to Kerbin without problems if you've got ninety units of fuel left in the tank when you're done. Eighty is bingo fuel - hit the deck or hit space. You can make it back on 75 but you're going to have to use good piloting. Seventy or less and you might as well land, because you're definitely not making it back. If you're still not used to Mun landings, begin killing your horizontal velocity about 8000 - 5500 if you're more experienced. Once your vertical, kill your burn, switch to IVA, watch your radar altimeter and do not fire up that engine again until you're down to 1000m above the deck (incidentally, the radar altimeter can give you an idea of where the deck is, and let you estimate how far you still have to go). Then it's just a matter of watching what you're doing. Note that this is not the most efficient method fuelwise, but if you're not an expert in Mun landings this oughta give you enough play to make it to the surface with between 80-90 units of fuel remaining.

Redesigned my Barn Burner Superheavys so that there'd be enough room for the zenith docking port. Sent one up to Typhon 1 and successfully docked it. Since the old Barn Burner was still nearby, I went ahead and docked it too (nadir port to nadir port). Numbers say she weighs 412.34 tonnes (TWR of 0.49 in that screenshot - 3.64 m/s^2 acceleration) and currently has 9,159.913 m/s of delta-V available. Of course, there's no lander attached yet so she's not going anywhere. Not yet anyways. The hope is to be able to use her for a Moho mission, though I may need to add moar fuel before that enters into the realm of possibilities.

My understanding is that the delta-V charts represent optimal averages for planning purposes only. They aren't hard and fast numbers for every case, so sometimes you can get away with having less delta-V available (and sometimes you need LOTS more). Think of it this way: if you wind up using less delta-V for a transfer than the map says you need, you've got that much extra available to you in the event of a screw-up later in the mission. Margin for error and all that jazz.

Which stat is that? I've got KER installed; haven't figured out the best way to use the in-flight data just yet (other than as a measure of remaining stage delta-V)

That sucks about as much as my computer spontaneously shutting down when I'm five meters away from docking....

SAS-core design again, I tried locking the steering on the back wheels. That's pretty much all I could do at that point to make it rollover safe but it worked: even at 20 m/s, it wouldn't flip over. Took it out to the shoreline to get a few extra m/s from the slope to the water; still wouldn't flip (though driving it into the water proved to be a bad idea). Did the first manned run near KSC over the weekend. With SAS and docking controls on and the back wheel steering locked, the only way I could get it to flip was to slam on the brakes and put it in reverse. Ejected two Kerbals and broke off the SRS; none of the Kerbals died, but obviously my roll cage design isn't foolproof. And when I tried adding lander legs for use as safety restraints, I found they were likely to be the part that broke off first when the rover rolled. Still trying to figure out what I might try next. Don't know if a restraint system is necessary at this point, though; the rover itself seems stable. Of course, I haven't gotten it up to sixty on Moho, either...... My next problem: figuring out how I'm going to get it deployed anywhere. The obvious attachment point (the top of the Modular Girder Adapter) has part of a ladder sticking through it, and so far I haven't been able to get anything else to attach to the node. Might have to resort to part clipping. Occurs to me I might try attaching something to the underside panel... Tried out the X200-8 design; had a tendency to blow up on rollover. Of course, fuel tanks have a very low impact tolerance in general, so that might be why. Rollovers also had a tendency to break at least one of the wheels. At least, I think it was the rollovers doing that; it could've just as easily been the weight of the tank.

I use Temstar's Zenith Booster family any more. They're a series of asparagus-staged lifters, the largest of which is capable of lifting 160 tonne payloads to LKO. Even if you don't use them directly, you'll probably get some good ideas from how they're designed (he explains their design philosophy here).

Docked a full heavy Barn Burner to Typhon 1. Damn thing got hung up on the Thunderbolt Superheavy's forward RCS blocks, of all things; had to turn the burner around to dock with the aft port instead. Numbers said the mission had 6500 m/s delta-V, not enough to get me to where I wanted to go (Moho; I figure the Superheavy Thunderbolt tug has the thrust necessary to make the orbital insertion easy). Attempted to dock another heavy barn burner. Couldn't make it; first Burner's outboard RCS tanks were bumping into the main fuel tanks of the others and the ports were only about a meter apart from one another. Might as well have been orbiting the Mun for all the more good that did me... Going to be redesigning the Superheavy Barn Burner, as might be obvious. Also continued farting around with the Hellrider 7, a SAS-chassis rover design. Was comfortable with the way the rollover tests had been going do far (thing was stable making turns at 20 m/s), so I loaded it with a crew for the first time. Put Seeley, Elny and Wenshel on it for a joyride around the KSC. Didn't tip over. Still wanted to do a rollover test with butts in the seats, so I put it in reverse and hit the brakes with it going 20 m/s. Seeley and Wenshel were ejected, with the rover landing on top of Wenshel (both survived); Elny stayed in his seat. So with that design, I either need to add some kind of safety restraint system (the lander leg idea didn't work; they were as likely as anything else to break off in a rollover) or just not throw the brakes on and put it in reverse at 20 m/s again...

Been reading up on rollover accidents. Apparently the U.S. government says a vehicle is relatively safe if it merely slides (i.e. two wheels don't leave the ground) when the vehicle is being fish-hooked (rapidly turned left-to-right-to-left etc.) at 50 mph (22.35 m/s). Wikipedia says "Generally, the higher the center of mass, the narrower the axle track, the more sensitive the steering, and the higher the speed, the more likely a vehicle is to roll over." So in KSP, the way you make a rover more stable is to keep the center of mass low, increase the distance between the tires, and lock the steering on at least one set of wheels. Occurs to me that an X200-8 tank weighs 4.5 tonnes on its own... Looking that stuff up has given me some other ideas to try out...trying to emulate a sway bar, for one thing. Seat belts for another (thinking a small lander leg might work; yes I know it's not the Kerbal way, I'm just thinking about how I might do something like that). Also been thinking about how I might improve the roll cage design. Apparently I made an awesome choice with the Modular Girder Adapter...has an impact tolerance of 80 m/s. I'm looking at replacing the struts with I-beams; same reason - higher impact tolerance.

I'd suggest an LV-T45 center stack engine with radially mounted outboard Aerospikes; that way you've got some steering authority (especially if you couple that with some fins on the outboard engines). If you have three outboard Aerospikes, each stack will need an FL-T400 and three FL-T800 tanks. That'll get you a launch TWR of 1.27 (bit lower than optimal but still enough to get into orbit) and 4,590 m/s of delta-V, and that's assuming a five tonne payload. Two tonne payload, that design will give you 5,133 m/s and a launch TWR of 1.34.

Onion staging works well if all you're doing is sticking around Kerbin (including Mun and Minus in that) and you've got a light payload. Heavier stuff, I'd recommend the asparagus. Actually, I'd recommend Temstar's Zenith boosters.... Here's a design guide on asparagus, if anyone's remotely interested. A one man pod with a chute and RCS for de-orbiting weighs as little as 1.35 tonnes. Five Mainsails for that is overkill...you could lift that with two FL-T800s, one FL-T400 and an Aerospike. You'd need winglets for control of course...

When, despite hammering the space bar like it's the damn fire button from Galaga, at 10 kilometers in Kerbin's atmo and coming in fast and with no structural failures of any kind, your chutes refuse to deploy. Still trying to figure that one out...