[Nuke]

its also important to make your apoapsis coincide with one of the nodes? correct? im wondering how much fuel ive been pissing away (its ok i always bring 4x as much as i need so i can screw around abit).

[watsisname]

If your orbit is already aligned with the target (relative inclination is zero) then the location of the nodes doesn't matter.  Otherwise, do your basic Hohmann transfer and then plane change farther out to intersect the target.

Having the nodes aligned with periapsis/apoapsis is good if you're planning to continue orbiting the same object and want to cheaply change the inclination later.

[newman]

One thing a lot of players miss out on is that you can drag maneuver nodes along the orbital path. So if you're going from your orbital path to a body on another orbital path, after making sure the planes are aligned, and with the target body still targeted in the map view, make a maneuver node and set a prograde burn maneuver until your orbit intersects the target's. If your node location is even close to being passable you should get two small light blue icons, one showing your position at closest approach to target, and the other showing target's position. Drag the node around the orbital path and adjust burn parameters (prograde / retrograde, up/down/left/right, yes I know there isn't really up or down or left or right in space but you get my meaning). Watch how the two icons move - your goal is to get them as close as possible to one another. Once they're close enough they'll disappear and you'll get an encounter / projected target periapsis. Now just fine tune to get the distance and inclination to your liking, orient in node's direction (marked blue on the navball), wait till you reach T-0 and burn (actually, if it's a longer burn, say two minutes, I like to split the difference by starting the burn early and finishing a bit late, it tends to even out. Then I tend to kill the node and use RCS to fine tune my approach while still far away and it's dirt cheap in the all powerful delta-v currency).

[crizza]

So, the maneuver nodes...
I add a node and the ship does the rest?
Added one, but when I reached it, there was no power left...guess if you have a probe as command section, you need juice to do anything...

[watsisname]

When you put in the maneuver node, an extra (blue) indicator shows up on the navbal showing you what direction to burn, a green slider showing how much delta-v you need, and a countdown to when the ship is at the node.  So you are doing the burn manually, the node just shows what to do.  Quite handy.

[TwentyPercentCooler]

After some...okay, a lot of extremely frustrating failures in building a viable heavy-lift launch vehicle, I've been messing around with atmospheric craft instead. Despite having the spaceplane hangar and runway, I still like to use the launchpad and take off vertically - it's a pretty good way to figure out if you've got enough thrust. I just managed to build a 3-engined beast that climbed out to 60,000 ft. and decided to go mach 4. I say decided because after I launched and leveled it out, it was so stable that I only needed to use a bit of aileron trim to keep it from climbing too quickly and it pretty much flew itself. I'll call that one a success - eat my dust, SR-71!

I also am trying to build a 4-nacelle X-wing sorta thing, but it's not working out at the moment, stability-wise, although the TTW ratio is more than fine. Also having a bit of success with some solar-powered aircraft, although you have to make the little jerks almost entirely out of tiny girders or the pitiful ion engines don't have enough juice to get 'em in the air.

I will tell anyone who asks that this is the best couple of bucks I ever spent on a game.

[newman]

After some...okay, a lot of extremely frustrating failures in building a viable heavy-lift launch vehicle, ...

Try this. Take a large orange tank, and attach another one below it. Now take a large white tank (half capacity of the big orange one) and attach it at the bottom. Put a mainsail engine below it. Now alt-click the top tank - this will copy the whole shebang. Attach it to the center tanks/engine row in a 4x symmetry mode. Now alt-click one of the rows again and again put it in a 4x symmetry so that you have a 3x3 arrangement (you should have nine rows of tanks with 9 mainsails below them).

Use a lot of struts to connect the tanks. If there's a lot of rocket left in the upper stages, use even more struts to stabilize it. Equip it with winglets and it'll practically fly itself upward. Also use those structural supports that keep the rocket in place until you launch and make them activate in the same stage as the mainsails. Things to look out for is to go easy on the throttle, and don't start the gravity turn too early. When doing a gravity turn do it with a much decreased throttle to cut down on the g-forces; large rockets love to fall apart otherwise.

With a few of these precautions, this heavy lifter put some very heavy stuff into orbit for me.

I will tell anyone who asks that this is the best couple of bucks I ever spent on a game.

Absolutely agreed.

[Nuke]

my space construction shenanigans continue! first order of buisness is to launch yet another tug. you can never have enough of these. a tug needs a dock or two, a lot of rcs power (same thrusters as normal, but on a stick! all that leverage comes in handy when maneuvering large and very off center loads), and powerful engines. fuel is not so important since you mostly keep it close to the same orbit the whole time. only doing short burns for sync orbit maneuvers. most manuvers are done with the rcs thrusters. the only time you need the engines is when your construction yard expands from a 200 meter sphere to a 10 kilometer sphere over the course of an hour, so fast engines let you dash out and grab that stuff before you have to do a sync orbit maneuver to get your stuff.

this one has twin nuke engines, and is a little lighter, and also not as wide as my previous design, i had trouble maneuvering it into position in a couple spots, less rcs spread so docking is a little harder. given the epic fuel economy of my previous tug design i decided to reduce the fuel quantity, and increase engine power by adding a second engine (this also balances out your load better). this makes short work of rounding up drift happy construction materials. twice the power means its a hell of a lot easier to grab that 4 ton piece of structure and bring it where you need it. i also decided to add more lights, because construction sucks while the sun is on the other side of the planet. this tug can also fly with or without a kerbal in the cockpit, and unlike the older tug has a big docking port up front and a small one in back, so it can hall stuff with either. here it is collecting girders from one of the container modules (its really just 20 tons of scrap metal glued together with bondo).

meanwhile at the kerbalstar there is a problem. i dont have any place to put all the ships i need to build the damn thing. they are all just docked to the kerbalstar which makes it hard to install new stuff without moving everything around. so i started work on a space dock with some of the surplus girders. oddly enough this mash of structure and ships maneuvers quite well. on with the task of gathering up all the crap from orbit and putting it together in one thing.

pretty much over night it grew to epic proportions. i forgot to take screen shots after i added each piece. but here it is about 50% "done" (done is subjective, i figure i will just keep adding to it as i need more parking space). happened to catch this awesome shot. you can see the station with no fewer than 9 ships attached.

the "final" piece. this closes the box, so to speak. this was a very hard maneuver to pull off. i launched 4 ultra light tugs (this is 4 of the 9 ships by the way) just for this manuver, of which i only used 2. this gave me a chance to test some construction techniques. moving this thing into place went smoother than expected, and it connected up perfectly the first try.

and there she is. a triumph of redneck engineering. and now with what i think is 11 ships attatched.


i also docked the first tank to the kerbalstar, however i neglected to hit f1. so you can just kind of imagine it.

 

[crizza]

I fail to build a heavy lifter... My maximum are five of the heavy tanks staked together, so I have 2x5 tanks with engines...but they are not enough...

[TwentyPercentCooler]

Meet the Solar Explorer II! This thing has such a ridiculous lift:weight ratio that it's almost impossible to land, but its only flight instability is a noticeable but non-divergent phugoid oscillation. Not exactly awe-inspiring, but shut up, it was fun. 

[newman]

I fail to build a heavy lifter... My maximum are five of the heavy tanks staked together, so I have 2x5 tanks with engines...but they are not enough...

I described how I build my heavy lifters above, but here are a few pics, maybe it'll help:




This 3x3 beast has 9 mainsail engines and has delivered all of my heavy interplanetary stuff into orbit (where it was typically added to by smaller lifters bringing in additional modules).




Another look at just the lifter stage, discarded in orbit. Note that it was carrying a full on interplanetary ship that eventually carried 5 probes to Jool's moons. I also used it to bring all my other interplanetary stuff into orbit.




Here's another slightly lighter version of a heavy lifter carrying a one-man space plane prototype into orbit.




Another view of the heavy lifter carrying a Jool-capable ship into orbit.

The thing to remember with heavy lifters is the following: just because it blew up when you tried it, doesn't mean the design isn't sound in principle. There are typically two ways a heavy lifter will fail. One, a part of it will lose linkage with other parts, resulting in the whole thing literally flying itself apart. You'll recognize this has happened if, say, one or more of the tank/engine rows suddenly detaches and flies off (usually starting a chain explosion that consumes the whole rocket, or if you're very lucky, merely destabilizes the rocket so the whole thing crashes down. Not so lucky now that I think about it, but definitely more rare. Once you lose structural integrity on the ascent a huge fireball is a given..) This is fixed by strategically interconnecting parts with struts, and being careful with the throttle.

Another typical way of heavy lifter failure is a failure on a decoupler; the g-forces created by the upward thrust of the lifter coupled with the mass of a heavy upper stage exert too much force on a coupler, usually the one connecting the heavy lifter with the upper stages. This is a common problem when lifting up something big and heavy. Once a coupler gives in, you'll recognize this issue by seeing the rocket's upper stage literally "overrun" by the heavy lifter, as it flies right through it before it all goes up in a huge fireball. Struts can help a bit, but you also need to decrease the forces on the decoupler by decreasing throttle and making a gravity turn later and with less throttle. Big rockets are especially susceptible to this kind of failure when angled, which is why I said to fly upwards longer if this is happening. Before making a turn, decrease throttle so you're still accelerating slowly (but not losing speed) to decrease the forces exerted on the decoupler.

Not using ASAS but manually steering the rocket in lower atmo can help too, since ASAS will keep trying to keep it straight by turning it back and forth, introducing vibrations along it's length. This can be very unhealthy with large, long rockets. A few well placed winglets will do wonders in terms of making large ascent stages controllable manually.

Also, now that we have docking, if something just won't make it into orbit, maybe it's time to redesign it so you bring it up there in more pieces and assemble in orbit.

[crizza]

Yeah, I noticed the linkage failure happens quite often when the enginges have contact with the landing pad.
I tried to copy the lifter layout, but I don't get the nine fuel tanks attached to each other.
My current lifter starts to roll and pitch, but while I can handle this it achieves not the orbit I want.
But I keep on trying. Right now I'm obsessed with an A-10 like jet.

[newman]

I did a follow up mission to my Jool Orbital one described previously in this thread. As a reminder, the goal of Jool Orbital was to use a single interplanetary craft to deliver 5 probes to the surface of each of Jool's moons, and additionally probe Jool's atmosphere with a detachable drop tank equipped with scientific and comm equipment, chutes, small probe core, etc. The mission was successful in everything but one thing; put a probe down on Tylo. As it turned out, Tylo is the toughest of Jool's moons to land on (indeed, maybe the toughest in the game, more about it later), and the little probe just didn't have enough delta-v to pull it off, so I left it in a 50x50 km orbit instead. The probe had a docking port that was used to bring it to the Jool system attached to the interplanetary craft, which left open the possibility of a future refueling effort, hopefully allowing it to land.

So I planned another unmanned mission to Jool. There were three mission goals:

- bring a Tylo probe refueling craft in a position from where it can enter Tylo's orbit and refuel the Tylo probe orbiting there;

- put an ocean floating probe in a Laythe ocean;

- leave the interplanetary stage in orbit of Laythe with, hopefully, enough fuel left to be of help to future manned missions to Laythe.


Here's how it all went down.




First, I brought the interplanetary stage into orbit and docked the Tylo probe refueler with it. The interplanetary stage was similar, but simplified a bit since this time around I didn't need it to carry 5 probes or drop the aft tank into Jool's atmo. The very long forward bit is the Tylo refueler.






Then I started playing with various design ideas for an ocean probe, testing it on Kerbin.




... and then it was time to dock the thing to the interplanetary stage. To the aft docking port, to be exact - which meant being careful that it's angled so none of the probe's "flotation devices" aren't in the way of the main nuclear engine's exhaust.






Another interplanetary ship leaves Kerbin.




What made this mission special is the fortunate timing of my Jool aerobreaking maneuver. After aerobreaking, I had an encounter with Laythe. I decided to utilize that, which paid off in fuel later on. This time around I was also more careful to fix inclinations early on so from the moment of aerobreaking onwards I was on the exact same orbital plane as Laythe / Tylo.








On approach to Laythe, I decoupled the Tylo probe refueler, leaving it on a fast flyby course. Then I set the periapsis of the Laythe Orbital low enough for aerobreaking, and had it enter Laythe Orbit.




With the Laythe Orbital safely inserted into an 80x80km orbit, I turned my attention to the Tylo probe refueler. It was left on a fast flyby and was now close to Laythe escape. A relatively short burn put it in a large elliptical orbit over Jool, which made a low-consumption transfer to Tylo possible. This proved essential later on.






Once in Tylo's orbit, the refueler intercepted it's target and docked with it.




Once I was happy with the selected landing spot, I filled the probe's tanks to capacity, and used the remaining fuel aboard the refueler to do a deorbit burn.




Then I decoupled the probe from the refueler, leaving it to crash on Tylo's surface. This part couldn't be helped - Tylo is easily one of the toughest places to land on in the game, and in fact this probe would never have made it down there in one piece had it not been for the refueler making that deorbit burn for it. Tylo is kind of the opposite of Eve, it hates visitors. Eve loves them, by requiring comparatively low amounts of delta-v to reach it, and by having the ever so helpful atmosphere handing out free delta-v like it's candy. It also makes landings easy since parachutes work. The downside is that Eve loves visitors so much it does it's best to hold on to them forever once they're on the surface. Opposite to Eve's psychopathic levels of hospitality, Tylo's the grumpy neighbor that would just as soon you didn't come. It takes tons of delta-v to reach it, and once in a 50km orbit, you'll still need to kill over 2 km/s to safely land. This is because it's almost as big as Kerbin, and has no atmosphere; onboard instruments show 80% gravity to that of Kerbin, which makes it's gravitational field almost three times as strong as Duna's. Tylo really doesn't help you land on it in any part of the mission - it makes your life difficult in every aspect of it. If anyone is planning on landing there, I recommend using a large lander, landing a small probe is really difficult there.




Due to Tylo's high gravity, this was my first landing where the engine operated for the entire way down. I even used the RCS to help it, for what little that was worth. RCS is painfully inadequate when it comes to fighting Tylo's gravity, and a small probe with 180 fuel capacity is very, very tricky to bring down safely here.




A view of the Great Wall of Tylo, as I call it. If you look better on the map view, you'll see it's basically a large slope that goes all around the moon, more visible on some places and less visible in others. In truth I have no idea why a large slope would circumvent an entire moon like that, but I'm sure there are people with bizarre haircuts over on History Channel with their own theories on this.




After running out of fuel a meter or so above surface, I was happy the probe was equipped with heavy legs. Anything less would have had unfortunate results. The probe nearly tipped over as it is, but eventually it settled down on the surface. Victory!






After a short celebration at the KSC, it was time to focus back on the Laythe Orbital, and land the ocean probe still docked to it down on Laythe.








This part of the mission was far easier than the Tylo part. Laythe is quite more forgiving, with it's lower gravity and atmosphere that makes chutes useful. The probe floated upwards just like during tests on Kerbin. Onboard instruments show a temperature of around 5 degrees at sea level. Another probe I landed earlier landed on an island on a hill some 1600m high; temperatures recorded there were -6. This does answer the question of why Laythe's oceans aren't frozen.. but I still wouldn't go swim in them without a space suit

So, I'm happy to report all parts of the mission were a complete success. I now have at least one probe on each planet/moon in the Kerbol system, and a ship in orbit of Laythe with almost 3000 units of liquid fuel along with it's accompanying oxidizer, which will be useful for a future manned mission.

[crizza]

My A-10 attempt failed, but I got a pretty neat delta wing, which flies well, but after using the timecompression it stalled, started spinning, in other words, I lost controll...
Jeb had his share of work to get the jet back under controll, while whirling from 10.000m to 1500...Damn...

[StarSlayer]

A view of the Great Wall of Tylo, as I call it. If you look better on the map view, you'll see it's basically a large slope that goes all around the moon, more visible on some places and less visible in others. In truth I have no idea why a large slope would circumvent an entire moon like that, but I'm sure there are people with bizarre haircuts over on History Channel with their own theories on this.

"What is most fascinating about the Wall is that it does not appear to be natural. The geological record suggests it is the result of a "glancing blow" by a mass accelerator round of unimaginable destructive power. This occurred some thirty-seven million years ago."

Great mission reports newman, having just gotten back into KSP after dabbling around with it months ago your operations are very inspiring.

[TwentyPercentCooler]

My A-10 attempt failed, but I got a pretty neat delta wing, which flies well, but after using the timecompression it stalled, started spinning, in other words, I lost controll...
Jeb had his share of work to get the jet back under controll, while whirling from 10.000m to 1500...Damn...

The time compression will mess with the physics - probably makes the computations less complex or less frequent to keep it from being a slideshow. A perfectly sound aircraft in 1x can totally vaporize itself in 2x. It just gets worse at the higher levels.

I finally got the hang of getting the heavy lifter into orbit without blowing it up - turns out my design was fine, it was just the execution that was lacking. I haven't shot anything really heavy yet, just unmanned probes and bits of space station. Now I have to figure out orbital rendezvous and docking; this should be fun. Thankfully my pieces have tons of fuel and monopropellant for my inevitable failures.

[crizza]

True enough about the time comprission, but using jet engines they stall at an altitude about 20000m and it will get realy ugly. 

[newman]

"What is most fascinating about the Wall is that it does not appear to be natural. The geological record suggests it is the result of a "glancing blow" by a mass accelerator round of unimaginable destructive power. This occurred some thirty-seven million years ago."

Great mission reports newman, having just gotten back into KSP after dabbling around with it months ago your operations are very inspiring.

Heheh, it reminded me of the same thing actually

True enough about the time comprission, but using jet engines they stall at an altitude about 20000m and it will get realy ugly. 

Yea, jet engines need enough air flow to function. I used to toy with the idea of a jet powered ascent stage, but it turned out impractical and inferior to SRBs in every way as low atmo lifters. I did make a one seater space shuttle / jet plane hybrid that worked fine. It'd launch vertically on top of a rocket, use it's in-built liquid fuel engines and RCS for orbital operations, then once it got below I'd switch to jet engines and land back on the runway. It even had parachutes for emergencies if I screw the landing up..

[crizza]

I...retire for today...build a lifter which worked fine, but then again I burned too much fuel for a correction burn to get my space station into orbit.
Then I added four SAS modules, reworked the RCS thrusters and then some of the fuel tanks with their respective engines say 5 seconds after launch "Screw you crizza, we take our fuel, disconnect from your lifter and fly our own way "

My jet did 1,500k metres above ground...while it is a stable design, I cannot build it...bigger. But I love to mount my engine block upon my wings

[TwentyPercentCooler]

"What is most fascinating about the Wall is that it does not appear to be natural. The geological record suggests it is the result of a "glancing blow" by a mass accelerator round of unimaginable destructive power. This occurred some thirty-seven million years ago."

Great mission reports newman, having just gotten back into KSP after dabbling around with it months ago your operations are very inspiring.

Heheh, it reminded me of the same thing actually

True enough about the time comprission, but using jet engines they stall at an altitude about 20000m and it will get realy ugly. 

Yea, jet engines need enough air flow to function. I used to toy with the idea of a jet powered ascent stage, but it turned out impractical and inferior to SRBs in every way as low atmo lifters. I did make a one seater space shuttle / jet plane hybrid that worked fine. It'd launch vertically on top of a rocket, use it's in-built liquid fuel engines and RCS for orbital operations, then once it got below I'd switch to jet engines and land back on the runway. It even had parachutes for emergencies if I screw the landing up..

I actually use some turbojets with ram air intakes for the first stage in putting lightweight probes/satellites up. To 15000m, where I jettison them, they take a ridiculously tiny amount of fuel. My second stage is one aerospike with one of the 1m long-body tanks and that's enough to boost to orbit with enough fuel left for corrections. Maybe not the best way ever, but I wanted to play around with air-breathing engines on a rocket and it worked out pretty well. Keep in mind the payload was a Probodobodyne core, a couple of girders and solar panels, and an ion engine. I might try something a bit heavier, though; the turbojets are a pretty awesome first stage for light payloads.