Everyone seems onboard for the kethane refueling base, so let's get to work on that. First, we need to actually...find kethane.
We start just before the beginning of Day 55 (Day 1 was when we launched the Minmus rocket. In theory. Don't remember if it actually was.) It takes only a bit over an hour before we blunder across some kethane.
Good, good.Now, to design the rig/shuttle/etc.
2,000 units of charge in those batteries, a universal docking claw, solar panels, lights, sixteen tons of fuel capacity, lights, and of course kethane drilling, storage, and conversion capability. And 4800 m/s of Δv.And a note so I don't forget my action groups: 1 is toggling drills, 2 is toggling the (white) landing lights, 3 is toggling the solar panels, 4 is toggling the (green, wide-beam) docking lights, and 5 toggles arming.
The launch rocket is a bunch of orange Jumbo fuel tanks with a Mainsail and six Skippers.
"The Mainsail and the Skippers, too, will do their very best/To make this joke again, again, until its hatred you confess."I didn't add struts, but after a brief wobbly moment all is well. The ascent is swift, but leads to the Mainsail overheating. Oops. Luckily, it stops...and not a unit too soon.
...Carp, I didn't put heat radiators on the rig. Oh well, how much waste heat can half a dozen solar panels , four drills, and a kethane conversion unit cause?It doesn't explode until 3,000 meters. Well...um...redesign time! But first...cathartic staging.
KSP just ain't the same without the occasional disaster. Even if they were intentional.
Hm, the rig's in one piece, and nicely explosion-decoupled. I wonder if I could safely land it?
Despite my best efforts, vertical speed continues to rise.
Those bits don't have landing legs, and they're falling like twice as fast as us. Better turn on the landing lights.
The landing lights at work!
That's a negative on the landing.
The landing legs succeeded in their duty, at least.I move up the boosters, and then toss on some struts.
The Mainsail overheats again. This time, I turned down the throttle some, to avoid kasplosions. We pass 3,000 meters without incident, though I have to occasionally throttle back a tick (I once thought that the higher atmosphere didn't diffuse heat as well, but now...who knows?).
As with many of these gimbal-reliant multi-engine lower stages, roll sets in. Thanks to computers being better at turning rockets than people, though, I don't miss my gravity turn.
I drop the boosters around 21.5 km above sea level. I throttle up, only to discover the Mainsail heating up again. I'm remembering something about orange tanks and Mainsails...carp. I need to be more vertical than not just to keep my vertical velocity from dropping without exploding my engine.
Well. This has turned out to be an interesting, if still safe, launch.
"...but tonight I say, we must move forward, not backward; upward, not forward; and always twirling, twirling, twirling towards freedom! ...From the bonds of gravity!"It takes a bit under four minutes from launch to when we have an orbital speed above a kilometer per second and an apoapsis outside the atmosphere. The estimated burn time for circularization (assuming we keep the Mainsail the whole way through) is a minute fifteen seconds; I get back to the rocket 42 seconds from the node. I start burning, though we're still (barely) in the atmosphere. Whoo.
Beautiful, just beautiful...what's the solar panel action key again?
There we go. Beautiful, ain't it?The engine is very nearly exploding, so I turn down throttle some. It doesn't help, but it doesn't hurt. Probably.
And guess what happens right after I type that?
...Probably not related to the throttle drop.I drop the (not-quite-empty...well, before hacing the bottom kasplode) fuel tanks on that suborbital trajectory and fire up the Poodle just as we pass the node. Estimated burn time: Two minutes and change. I hope we don't hit the atmosphere. Again.
Six minutes. 1:12 of burn remaining, probably. Almost two km/s already. Still suborbital. Maybe 20% of the Δv to go.
Seven minutes. We're just barely orbital (technically; we'd hit a mountain or lose orbit from atmospheric drag if we didn't burn that last 74 m/s).
We enter the atmosphere again. I keep burning, until we run out of node and the craft starts spinning. Periapsis: 62.6 kilometers. Plan: Wait until we're at apoapsis (about 119 kilometers and 19.5 minutes out, currently), then circularize.
Fourteen and a half minutes after launch, we're out of the atmosphere. Apoapsis is almost 114 kilometers and twelve minutes away. It'll be easy. 40 m/s, six seconds at apoapsis. Circular orbit.
In the end, it's not quite as circular as planned--113.5 by 110.6--but it works.
And the sun rises.We're 5.8 degrees off Minmus's plane. At the descending node, near periapsis, we need a 224 m/s burn to get 0.1 degrees off. We still have over 4,100 m/s left, though, so we're good.
I notice something else about the burn.
Minmusrise.No reason to wait an orbit between burns, neh?
Easy, but not idealsy.
Is it just me, or is it really easy to get a collision course with Minmus given that I'm firing from Kerbal orbit and it's only like 120-odd kilometers across. It's like hitting the northern half of Wales from the Moon, with a rocket-propelled golf ball or something.(Remarkable how narrow the line between "crashing" and "not even a close encounter" is.)
I eventually go for a 916.4 m/s burn that leads to me crashing if I don't do something about it. And something I will do!
Trying to get the ship to line up with the node is...annoying. I should have put some reaction wheels or RCS or something on here. The batteries are full, that's no problem, but the probe's tiny reaction wheels are trying to spin a craft that's currently a bit over 37 tons. Still...it eventually works.
The burn is estimated at 2:32. I warp to two minutes ahead of time, planning to burn at T-1:16.
It might be hard to tell, but we are heading for Minmus. For a landing, and hopefully not only in the right spot but without crashing.Burn done, let's see how far we deviated. I hit the burn
amount perfectly, within a dozen centimeters, so it's all down to the timing of the acceleration. (Inevitable, really.)
...
I hate you.At least we won't crash...
Well, we fiddle with maneuver nodes on the centimeter scale.
Wait...is that an encounter after the escape?Clearly, a hyper-efficient Oberth-affected burn won't work. We need a farther out, less efficient but more precise burn to trim our encounter to...well...an actual encounter.
Sadly, the first burn I plan (4.5 hours out) isn't much better. Trimming will need to be very close, indeed.
I've been discovering that "no periapsis," despite common sense, does not mean "I'm about to hit the world in question". It can also mean "Screw you; you're barely in the SoI but I'll make you think you're going to hit it, so you fiddle around trying to bring the periapsis enough to not crash. And/or, it'll make it impossible to tell how to adjust your trajectory to make it closer to the target."
It's a pain. Stupid game. Eventually, I schedule a 1.9 m/s burn seven days and change out. My vessel weighs 29,153 kilograms at the moment; it has a thrust of 220 kN, and will hence accelerate at 7.55 m/s
2 at full throttle, which means that at 1/3 throttle it would take...less than a second to shift. One tick is almost four seconds. So, not a huge burn.
There's a week to wait, so I spend that watching the kethane finder find kethane.
Scan scan scan...
Memo to self: Scan slower.A little testing determines that, in this orbit, I can't warp faster than 100x if I want to avoid skipping hexes. With this knowledge, I net a more complete knowledge about the kethane deposits of Minmus. The moon's
speckled with them. Still, two and a half days--even Kerbal days--at only 100x time acceleration is a bit dull.
There's one particularly large patch of kethane we've discovered...
Is it in a crater? It looks like it is. Maybe a kethane-coated meteor hit Minmus some millenia ago?A couple other such spots pop up as well, but that was the first and (arguably) the most notable.
With the help of the Kerbal Alarm Clock, we return to the rig with three minutes to the node. Good thing, because a solid fraction of that time is needed to spin into position.
Alright. Burn done, with the indicator at 0.0 m/s and jittering between red-X and green-check. Let's see how we did.
You can't see it, but this is jittering as well....Good enough.
We've a day before we hit Minmal influence, so let's scan for kethane at 100x time acceleration.
Geometry: Generally agreed to be the prettiest part of math.
Two more probably-sizable deposits.After KAC alerts us, we jump to the rig being in Minmal influence. We turn retrograde and start burning, hoping for capture. I watch the Orbit speed drop, the Escape marker shift. I get into an ugly-but-functional orbit, making us drop below the half-fuel line.
Almost landed.Next, to lower the orbit.
Seven days out...wait, why don't I just lower the periapsis to 10,000 meters from up here?
Much better.I could switch to the kethane scanner for the next four hours and change, but eh.
I went a bit too far, bringing the periapsis down to about 2.3 km, well low enough to smash into some of Minmus's higher mountains. Hence, I turn prograde and burn slightly until the periapsis comes around 14 km.
Now, a circularization burn.
Not shown: Jittering about. Hell if I know why.Four days out...enough to switch spacecraft.
But not before a shot of the Kerbal system.Another large patch of kethane is located, notable for its location.
We were so close to striking green gold!
Nice shot.Anyways, after more scanning, we're back at the rig. 60 m/s, eight seconds, burn four out. First, turn it the right way.
A lovely scene, marred only by the weird orange solar panels and the darkness.We're now in a 15.6/14 kilometer orbit above Minmus, roughly equatorial. Now, we need to choose a landing spot. It obviously needs to have kethane, and ideally would be near the equator, for easier rendezvous with craft in a standard equatorial orbit.
We have one tile of kethane precisely on the equator. That should do, especially given its neighbors.
Nice how things work out.But that will be
in another episode tomorrow. I've already spent ~3.5 hours on this, although admittedly a fair portion of it was waiting for time to pas at 100x time acceleration.
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Topic: (KSP LP) Bay12 Space Program: Conical Difficulties (Read 72344 times)