I was going to go fishing today, but it's been raining all day. So, instead, I decided to do another episode. This will probably be the wordiest one so far.
Remember that Duna mission we picked up 3 episodes ago? It's finally time to go!
Where we left off:
Science: 80.8
Funds: 504,053
But first, a word. I'll definitely be using MechJeb to calculate my transfer window. In the past, I've done things like holding a
protractor up to my monitor to measure
phase angles, though after a while, I just started eyeballing the angles using the chart as a guide. Not as efficient, but less of a pain in the ass.
This reddit post , describes an even easier technique. So, if you don't like using mechjeb, there's two good methods for you to use.
So, lets upgrade the mission control and check on the missions. There's a
docking mission I take, because it has no deadline. Even if we never complete it, the advance is ours to keep forever. We'll probably end up completing it later for the 122K reward. I also take a "build an outpost on Ike" mission. It has a 540K advance, and a 35-year duration. Plenty of time to get it complete. I've never played a game that lasted 35 game years. And it has a 1.5 million completion reward. I do the same for a rescue mission in the orbit of Minmus--175K advance, 400K reward, 12 year mission. Plenty of time. I pick up a few more missions that have big rewards that we'll do after we get back from Duna. Our mission roster looks like this. I was hoping for a "flyby of the sun" mission, since we'll do it anyway on the way to Duna. But it's not there. After all of the advances, we have 1.5 million kerbucks, which is plenty to build some nice craft.
So, let's get back to our main mission, exploring Duna. Remember the
Kerbin SOI Lander?
We're going to re-purpose that bad boy into an interplanetary probe ship. We're going remove the fuel lines (so that each leg has it's own independent fuel source), remove the manned pod, and place a probe core and mechjeb component on each individual tank of fuel. We'll also put a thermometer and antenna on each tank, because all exploration missions require we do some science. Finally, we'll put parachutes on each tank. This will give us five science-capable landing probes. They're never coming back, so we don't waste weight on landing legs. I don't care if they tip over.
Why five? Because almost all interplanetary missions need them. 2 for the main planet (landing and orbiting), 2 for the planet's moon (landing and orbiting) and one to send home--because we almost always get a mission that says "return from Gilly" or "return from Ike". That lets us leave probes in orbit and on the surface for future "return science from..." missions that occasionally crop up. That's like free money, yo.
So, this one launch will allow us to explore duna, ike, and send a craft home, and hopefully complete a lot of missions along the way, and make a lot of kerbucks with this one launch. And we need to. This is a half-million dollar ship after re-designing the launch stages. This is what we end up with:
So much prettier.
And it flies! I have the fairings set to eject just after the bottom fuel tank drops off. That's about 22km up, which is fine. I've put RCS and wings on the lower stages, because this big ship is unwieldy, and those little suckers help keep it stable and steerable.
I launch straight into a 1250km orbit, and we have 1250dv left to get to Duna. Just enough. The reason for the high orbit is because at 100km, we can only warp at 50X. At 1250km, we can warp at 10000X. If you don't want to spend the fuel, be prepared to spend a lot of time waiting that 200 days for the transfer window. You will save about 300dv in fuel if you make the wait. But at 50x warp, it's something like a 20 hour real-time wait. We could just park the ship up there and perform lots of other missions while we wait for the transfer window. But I'm not down for that. I promised you Duna this mission, and we're going to do it.
Mechjeb calculates a 750dv transfer to Duna. That'll leave us just under 500dv to circularize when we get there. We'll have to do some aerobraking. Our inital burn gives us a 22 million km insertion. We want to lower that some, so
set up a node to fine tune along the way. This is far cheaper (7.7dv) than trying to do it in Duna's SOI. A little push from far away translates to big changes over long distances.
But before we execute that node, let's check on our
science lab. Those guys have been working away, and we need to collect some science. Almost 500 science gathered, and 400 data left, and still making a half a point of science a day. The Mun is blocking our solar panels at the moment, but we have 8000 units of electricity, so we can go ahead and transmit it now. It'll take nearly half of our batteries, so I'll warp until I'm back in the sun to charge back up. If I leave the ship now, it'll still be at half batteries when I come back.
Back to the Duna probes: Warp to the fine-tuning node and execute it. Then warp another 177 days to Duna. Because this is an unweildy ship, I have to make a couple of more fine-tuning adjustments along the way,
but I arrive with a periapsis at close to 200K and 476dv of fuel left. There's a couple of days before we hit our periapsis, so lets go
back to the science lab and get 499 more science. Our lab is down to 300 data and .4 science a day, so lets add to it. We add materials science (+125), and atmospheric scan (+60) which brings us back up to close to 500 data in the module.
Back to the probes: Duna's atmosphere starts at 50km, and it's thin. If we spend 8-9dv to get an
18km periapsis, we should be able to aerobrake into orbit without spending any more fuel. And the atmo's so thin, we won't even come close to burning up.
We make it with a 1.4 million meter apoapsis, so we change the
periapsis back to 18km at the peak and make another run at aerobraking. The second time around doesn't produce
any heat effects at all, and I end up with an apoapsis of 271K. After spending 100dv to circularize, I have about 300 left in the main engine. We'll spend that to get us part-way to Ike later.
After transmitting a temperature scan, we've compled two parts of the Duna mission:
Orbiting and
transmitting science from space. Time to peel off a probe and land it. So, right click on one of the decouplers around the main tank and detatch it.
You'll have to activate the engine by hand, since we didn't stage it, so right click on the engine and turn it on.
We have enough dv (3900) in this probe to do some orbital maneuvers before landing, so we bring it down to a 100km orbit before landing, so we don't bump into our mothership. Then I pick as
flat of a landing site as I can. Craters are good. Even though we don't have legs, we still don't want to explode if we tip over too hard. Between the SAS and the flat landing site, I can probably stay upright. Or, at least, not hit so hard if I fall over.
I go off to make some lasagna for lunch while Mechjeb handles landing. Don't worry--when we get to Gilly, you'll get to see me do this by hand.
I hit the SAS as soon as I touch down, and even though I'm at a tilt,
I stay upright! I transmit a
temperature scan, and complete the
Duna exploration mission.
Before we finish the episode, we need to peel off another probe and leave it in low Duna orbit, for future "transmit science from the orbit of Duna" missions. So we switch back to the mothership, and decouple a tank on the opposite side of the first one (for balance), and leave it in a 100km low duna orbit. You'll notice your dv on the mothership go up as you shed the weight. We might even have enough to get to Ike with it.
We'll leave the mothership here, for now, until we get the explore Ike missions. This will let us complete those missions without spending any more money.
Final results:
Science: 1230.4
Money: 2,402,851
I have 211dv of fuel left, but I want to save that for slowing my re-entry.
