Alright. We have one vote for attempting to use KAS and one vote for attempting a rendezvous. Since I suck at rendezvouses and microgravity EVA, we're going to do a KAS refuel. First, I'm going to look up how to use KAS, since we seem to lack the containers. Sadly, it seems that without having prepared for this, it'll be...tough. Or impossible, more like.
I look over the options I have. I look at my rescue craft, hoping to see something I could maybe make work. I remember one little bit of KAS...could it work? I test my plan out, sending Bill and Bob into a secret late-night test.
...Oh yes, yes, this'll do
just nicely...if it doesn't break the game.
First, the refueling craft.
23.5 tons of fun! And fuel, although there's a bunch of not-fuel too.
Very similar to the rocket already on Minmus.
Heptaskipper asparagus. It would look cooler if I knew how to zoom.Completely unmanned. Completely in need of struts. Once we strut it, it's ready to go. And so we launch.
Dropping the first tanks...but that's not all we drop...Once we drop the first pair of tanks, despite having a 1.33 TWR, our speed starts dropping! Whatever caused this, it is reversed. We're still spinning, though. I may need to use the Smart ASS for the gravity turn; I don't like relying on it, but I can't deny its results. And that it knows how to deal with ships spinning, as long as they're not crappily-designed planes in a spin. (But then, I can't fly those either.)
Come 9500 meters, we drop the second set of tanks. Our TWR is still 1.09, so we're good. I have MechJeb execute the gravity turn on our spinning ship and...it tilts north despite me asking for east...starts going easter...it's doing better than I would. I wonder if the fuel transfer is what's causing the spinning? Soon we're going horizontally north-east. Then slightly down and east. Then horizontally southeast. Then mostly south mostly vertically, then vertically.
...Well, it's still probably better than I could have done in that situation. Let's add some winglets. Six of them should do.
Adding those, the craft goes straight. The first pair of tanks, engines, and winglets are dropped...starting to spin. SASS is having as much trouble as SAS. I drop the next two tanks, try to turn, and...well, it goes awry slower and slightly less than last time at least. The nose circles the mark, never dipping below the horizon. Eventually, we get there, still spinning of course. We pass 200 m/s just after 13 km ASL, so that's nice. Time to apoapsis is remaining at a constant 4.7 seconds, though, which isn't ideal. I have MechJeb angle the nose up (again, spinning), and that seems to work well enough.
One nice thing about the spinning: It makes sure the engines won't hit us when we drop them. Less-nice thing unrelated to the spinning: With one Skipper, our TWR is only 0.66, which is less than one. Time to apoapsis: Dropping. MechJeb: Requested to point us straight up to slow the inevitable. Well, inevitable unless the vessel mass drops low enough, fast enough.
22,000 meters ASL. Apoapsis in six seconds (theoretically; it's only dropping maybe 0.1 seconds per second). TWR 0.7. Pointing vertical.
22,800. "One second." TWR 0.74. We start falling after hitting 0.75.
Hm. Our upper stage has 520 kN of thrust...less than the 650 of a Skipper. Damn. But if I could just activate all of the 909's at the same time...but I can't. Damn.
22,300 m. TWR 0.8. 21,250: 0.85. We're down to a quarter of our current fuel.
...If we ditched the Skipper, we'd be dragging a lot less. But nope, TWR is about the same. Damn.
Alright. How can we do this? First, I'm ditching asparagus staging in favor of more normal staging. Second, I'm halving the fuel capacity of the last Skipper, and adding eight rather than six LV-909's. I'm also adding three radial engines to supplement the Skipper, and finally eight giant solid rocket boosters as low as the game will let me.
This won't cause us issues, right? Just to check, though, let's hit the launchpad for a decoupling test...
The explosions continued for a while. The only surviving bits were two radial engines and a Poodle, and maybe something else jetting off into the distance that I couldn't switch to.Um. Alright, let's try moving the LV-909's up as high as they will go.
If we wait for the SRBs to turn off before releasing them, we'll be fine. I think.Naturally, the ship starts to rotate once we start it up, because screw you GWG. Aside from that...SRBs are
intense. We have a TWR well over three by the end, and when the boosters run out, we're over 11 kilometers up and over 400 m/s. The spin, of course, helps keep the boosters from hitting us. I note that, once we rise above the lower atmosphere, we'll have a TWR of 1.24 or 1.25 (the game can't decide). I order the turn and, once it's done, start the burn. Sadly, the spin makes it hard for MechJeb to turn, so we start falling. Once we're pointed roughly the right way, I fire up the engines, hoping that the gimbal would help. It does.
This would look so cool if there was light to see by!We're still falling, of course. And we burn what fuel we have fast. And we--oh screw it, I'm adding two winglets per SRB and starting over. Hopefully we won't have all that spin.
Launch successful. No spin. With help from M.J, of course. I'm glad to not have to micromanage roll.
This stage actually looks pretty cool even without light.Anyways. Boosters dropped, gravity turn started. The nice thing is that, by the time you've figured all that out, you're out of the lower atmosphere and don't have to worry (so much) about losing speed to the atmosphere, so ending so fast isn't so bad. Anyways, by 26 kilometers up (roughly double what the boosters gave us) and 430 m/s (roughly what the boosters gave us), we're ditching that little...um...anti-tug, so...gut? push? Anyways, it's gone, we've just got eight LV-909's and a Poodle giving us 0.95 G of thrust. It's enough. I need to fiddle with the angle of ascent, though. MechJeb makes it easier to change your attitude, but it doesn't reduce the desire to micromanage it; it merely maximizes the efficiency. And precision. And results.
The Poodle cuts out before we or the apoapsis are out of atmosphere. Uh-oh. I mean, we have plenty of Δv in the top stage, but...do we have enough?
I set up a quick maneuver node for a circular orbit, and need to start burning basically when I switch back. I turn on the engines to help gimbal down, but...faster, faster...almost there...close enough, throttle up!
That stage lasts through orbital insertion with a bit of fuel left. Stellar. I plan to adjust inclination with the rest, and a bit of the last stage's fuel...but then notice a mistake.
No. Fracking. Solar. Panels. That was a waste of time...
I add solar panels, then relaunch.
Sun. That'll keep us from running...um...dry?Knowing what to do makes it a little quicker and easier. (Not switching windows every 10 seconds to blog about the launch probably helps.) Oh, and did I mention I remembered the solar panels?
How's THAT for way more power than I need? Especially since I don't even have any batteries onboard?I'm still on a suborbital trajectory when I ditch the penultimate stage this time. The slightly asymmetric design required for me to keep this kinda secret throws off my balance, though, which sucks since it means I start spinning. And start falling, into atmosphere. I start burning, until I realize that I'll just rise out the other side. Since I'm near periapsis, I order MJ to turn retrograde, warp to apoapsis, fix my direction a bit, and burn prograde. It's pretty easy to get into a circularish orbit, 169x166 km. I rename the ship to distinguish it from the failed one, then set up an inclination change maneuver.
Nice. 0.1 degrees is pretty darn good.I turn to the node and warp out there. Then, I burn...at full, stupid me. Why did I feel the need to try and hide my plan so slightly and clumsily?!?
Inclination difference: 3.7 degrees. Not good enough. I need to get a maneuver node at the other side.
Well, that's nice.I try to burn slower, but determine that my thrust is high enough that I can't burn as slow as I thought I could. Still, I burn slow enough. I screw up by not pausing while typing the last bit, so I end up 0.2 degrees out of line, but...who cares?
I set up another maneuver node to get me close to Minmus.
Is...is that a collision course with Minmus? I think I'm almost done, here.
Close, but still a bit low.
Very precise, but I'm still pretty sure that's a crash.
(And I couldn't duplicate the thing where I didn't crash into Minmus with 20 or 21 m/s at radial-out.)
That'll do, pig.So. We're ready.
The burn-time indicator was pretty far off, especially since if I go above 2/3 throttle I'll get off-center; the encounter won't be quite as nice as I had hoped.
Understatement.No encounter? No closest approach, even? Wow. I need another maneuver.
Another collision course? Why am I so good at these today?
Not my best encounter, but it'll do.I screw it up--there's just too much thrust. I don't have an encounter, but at least I have a close approach. That's it, I'm disabling half the engines.
Not bad. Not likely to stay that way, but still!Maximum thrust: 120 kN. With three engines and, say, one-third thrust, that's still 120 kN. With a 5.5 m/s burn and a 15-ton vehicle, we'll be accelerating at eight m/s
2 for not enough time. So. Each tick is one-fifteenth of 100%, it seems; that's 1.6 m/s
2 for three and a half seconds. ...I don't much like this. Well, I'll just tap shift a few seconds out, then x when I'm out of Δv needed.
Good enough.It takes a week for the craft to reach Minmal influence. Once it does...
171 m/s with 360 kN max thrust and a 15-ton craft...at max thrust we have 24 m/s2 for seven seconds and change. At two-thirds thrust, it's just under 11. Just under two-thirds for twelve seconds it is.My eventual orbit isn't perfect, but it works. There's just one minor issue...
Don't see it? Look for the terminator. Good advice, whether you're a solar-powered probe or a Conner.I said minor, even though we'd quite possibly run out of power before landing if we took too long. Why? Because I intend to come down hard and fast. (Until I slow down.)
Time for math. (It's how I make up for heavy MechJeb use.) On Minmus, the surface acceleration from gravity is 0.491 m/s
2. I'll assume a constant pull of 0.49 m/s
2 to keep things simple. If I kill my velocity at 2,000 meters, it will take 55.33 seconds for me to reach an altitude of 500 meters. Thus, I will have accelerated to just over 27 m/s by then, and could kill off my velocity in three seconds, which would take me less than 75 kilometers down.
...Let's see how far I can take this.
If I waited until 200 meters, I would accelerate to nearly 30 m/s, which would take me 3.75 seconds to burn off, during which time I would fall roughly 56 meters. The remaining 144 meters would take 17 seconds to fall, and I would accelerate to 8.33 m/s. The crash tolerant for the fuel tank I'm using is...6 m/s. Shoot. Well, if I waited until 100 meters, I would accelerate to 30.5 m/s, which would take 3.8 seconds to burn off, which would leave me roughly 42 meters above the ground; my final impact velocity would be just over 4.5 m/s.
So, in short, my plan is to burn into a crashing trajectory with Minmus, kill my velocity two kilometers above the cold, hard surface, free-fall, slow myself a measly hundred meters above said surface, and then fall the rest of the way, trusting that my rounding, approximations, and poor understanding of KSPhysics won't leave me splattered.
I'm quicksaving before I land, by the way.
I fiddle with the retrograde and prograde markers on a maneuver node and discover, much to my surprise...
Yay!...that I don't need to burn normal or antinormal to hit the spot! I try to overshoot a smidge, so I will be more or less over the site when I kill my velocity. Now for maneuver math!
50.5 m/s of Δv. 8 m/s
2 of acceleration. About twelve seconds. Works. Also works: Eight at twelve. Half throttle it is.
...Geez, just thinking about this maneuver is making me shiver. I'm not envying future-GWG (past-GWG to you), who has to actually do this...
The math works out. The math works out. The math works out. The math works out.
GODDAMMIT!I have other problems right now.
I turn the rocket prograde and, on the map screen, burn slowly. I watch the line flow across the Minmal surface...not straight towards the site. Time to burn normal, because I screwed the perfect stuff way up.
Yes!This is working okay now. I zoom in to get even closer, and to overshoot just a little. I see why some experienced players don't use maneuver nodes much.
There we go. Overshooting just a little. Quicksaving. Just...significantly over 45 minutes until we come close to the ground. I warp ahead and--aw crap.
Curse you, basics of planetary motion!Another maneuver. 18.2 m/s. At one-third acceleration (8 m/s), that's a bit over two seconds. At two ticks of acceleration (3.2 m/s), that's a bit over six seconds. I wish I didn't have to calculate so many maneuvers.
We're close.
Very eccentric orbit there.I hope that we don't get screwed over by this. Anyways, I burn normal to get closer. Then, I burn retrograde, because...
In theory, we'd orbit forever. In practice, we'd plow into the side of a cliff eventually.It doesn't take long, and we're only a few kilometers above the surface. It's now just a matter of waiting and performing my plan:
1. Kill velocity at 2,000 meters above the surface.
2. Kill velocity at 100 meters.
3. Try not to panic.
Well, step 1 goes awry. See, it takes a bit to kill my velocity, and while doing so I fall. Fast. The speed of velocity-killing is further hurt by my slight off-centeredness. I don't actually kill my velocity until I'm
one kilometer above the surface. Time to re-math.
If I kill my velocity starting at 70 meters...I'll have 21.33 m/s to kill, and at 1/3 thrust I'll kill it in 2.66 seconds, falling 28 meters, leaving me with 42 to deal with. Oh. That worked nicely.
Alright, just gotta quicksave, then wait until I'm 70 meters above the ground, then burn straight up at 1/3 thrust, then fall. Minmus's gravity is low, it'll work. Trust the math. It's just algebra, you mastered that years ago.
Oh God those numbers are going down fast.
500 meters. 19 m/s. Almost exact agreement. So close to landing.
150 meters. 27 m/s total velocity.
Above this screenshot is an explosion.CRAP I DIDN'T BURN IN TIME OR ENOUGH! Or something. Could someone double-check my math?
Another explosion. I need to turn my screen brightness up to almost 100% (I usually manage it at 0%) to see what survived. Not much. Well, that's what quicksaves are for.
I will start at 100 meters this time. I slightly overkill my vertical velocity by 18 meters, going up to 19 before going back down.
Before I unpause...it'll take 6.23 seconds to land. 6.23*0.491=3.06, which is easily within crash tolerance. It'll be okay.
...GODDAMMIT I HATE YOU MATH.
Thankfully, I quicksaved right before the crash, so I should be able to manage a gentle landing. I do, but burning right before means I pogo up, and since I wasn't quite straight up-and-down, I'm on my side. My true altitude shoots up; either I flew off a hillside or I screwed that up
way more than it looked like.
F9.
I barely get any time before everything explodes. Great, when did I re-quicksave?
F9.
I pogo. I go over the drop.
F9.
Things explode.
...
Alt-F12. Nothing is selected. Alt-F12. F9. Hey, I survive this time!
...
Shut up. My math failed, what option did I have?
Anyways. I've landed.
Kinda.We're rolling, though. And while we roll, we lose electric charge. And when we're out of electric charge...well...
Not much I can do. Might as well answer your question. What was the test?
(Just pretend you cared.)
Simple, really. I put two pipe end points on one vehicle and then took one off, then linked them.See? I can just yank the spare end off and connect them! In theory. Pretty sure I can't do it from over 15 kilometers away. Or while rolling down a never-ending hill.
...
So.
Um.
What now?