Kerbal Space Program Stories

[Canem]

Well, first success in the new rover R&D program. It’s amazing what you can lift with 3 Mainsail engines. Two Thoroughbred boosters were also used to get the TWR on liftoff up to a reasonable number.

So the goal is to get this thing to Duna, but to test the deployment method maybe something a bit gentler to land on like Minmus. Lets pop the shell shall we?

TaDa! Built an 8 wheeled rover with a MK 2 lander can, 3 big batteries, all the usual science gear and a small tank for running fuel cells.

Well I left about 1800 dV in that other stage, but that’s good. This is an early test for the Duna mission, so with a few tweaks (nuclear engines?) I should have dV to spare at the next launch.

So here’s the plan: get in a low and slow orbit around Minmus. Drop the 2nd stage and start the landing engines. Set it down like any lander, then with the 2 reaction wheels turned all the way up, tip the whole thing over and hope the wheels can take the drop.

There’s also parachutes on top of the rover. When this thing goes to Duna I might try dropping the lander stage early and just air-dropping the final distance.

Carefully now…

So it turns out that the reaction wheels on Minmus were plenty strong to actually stop the tilt at any point. I could have even stood the thing back straight up I think; but here I just went for it to set the rover down and undock from the lander.

HAHA it worked!

Now if I design it right I should be able to put a low docking port on the Minmus base I’m contracted to build, so maybe I can just back the rover right up to the port.

Either way, mission success! Soon: to Duna!

[SirDrew]

@Canem Nice! That large rover on that tiny lander looks Kerbal! Think it’ll be manage-able in Duna’s atmosphere? Also, Duna’s surface gravity is ~6x Minmus’s, ~2x Mun’s and 1/3 Kerbin’s in case you want to estimate the amount of torque you actually need for control.

Watching myself actually land, my comment about 38k pe actually seems rather on the high side.

[Syonyk]

Did you play Space Trucking in the background when you had your space truck? That’s a… very Kerbal looking lander. I love it!

[Canem]

@SirDrew

Think it’ll be manage-able in Duna’s atmosphere?

Tonight I was determined to find out!

Design updates after Minmus: added droguechutes to the lander stage, more solar panels on the rover, a bit more fuel, and most important was the extra reaction wheel to ease the tip-over stage of deployment.

Onward and upward

Feels weird to drive a rocket from a bus-cab

Sheesh, picked the worst possible transfer window there. Had to warp nearly 300 days to get in position for the first prograde burn.

But we made it with dV to spare! Starting the approach…

Periapsis currently ~20,000m. Retrograde set to surface this time.

gulp… I’m going to wish I brought more heatshields arn’t I?

Woah, that… that actually worked. Coming in so shallow and at about 1300m/s there wasn’t any heating at all! The ablator lost 3 whole units. That’s it. Cool!

Coulda gone with full radial chutes here. Droguechutes were very stable though, worked out very well. Speeds kept trying to build to over 100m/s, but we had plenty of thrust for a couple close hoverslams and a soft landing.

Mission success!

The tip-over went fine. Glad I added the extra reaction wheel though. The rover is very stable in Duna gravity.

Never exceed speed: 15m/s in straight travel
Maneuvering speed: 7m/s for aggressive turns.

I’ve been playing with traction control and such to try and improve that. I did flip it once, and broke the top solar panel (dang it!), but with that rear reaction wheel turned up to 100%, literally just hold q and it rolls right side up again no sweat.

Also the fuel cells are not much help, I didn’t realize that lander stage was sucking fuel from the rover tank through the docking port, and it’s almost empty. Oops, lesson learned. Transfer fuels before release next time.

Lets get out and stretch our legs a bit. We’ve been sitting in this cramped lander pod for [checks watch] 2.5 years now.

gasp… My god! It’s made of sand!

Totally worth the 2 year trip and funding spent to find that out.

[SirDrew]

@SirDrew

fuel ducts not working and disconnecting when spread across docking ports,

Except I just had fuel ducts work across docking ports. Guess I still haven’t figured that part out.

@Canem

found out 1 of the small round batteries isn’t enough to complete the transmission from Mun in one charge. ugh…

… Which is only a temporary delay if you have time, a way to charge them, and the antenna set to “require complete”.

@Canem I think I see expansion parts in some of those Duna shots? How do you like the expansion(s)?

Edit: radial mount chutes have an angle setting so the chutes look nice / don’t clip into each other. Last I knew the bigger the angle the more effective the chutes were also, and the effect gets more dramatic as you go from 2 radially symmetrical chutes to 8.

[Canem]

@SirDrew

I think I see expansion parts in some of those Duna shots? How do you like the expansion(s)?

I like Breaking Ground! Gives more actual stuff to do once you’ve landed, especially building rovers. For my duna mission I had a reason to drive around scanning duna stone, blueberries, sand dunes, and an asteroid. Haven’t figured out how I’m going to get the duna stone sample back to Kerbin yet however…

I forgot that I only brought a lvl 1 scientist with me too, and a single solar panel for the deployed science modules. Soo… that’s not very useful, since it takes 1 power just to run the command station. Time to send up an automated cargo lander!

[SirDrew]

I just completed the Rosetta mission to dock with a comet. Score 5500. I was surprised how easy everything was. Lots of fuel leftover, zeroed velocity with comet, detached lander probe, moved toward position to attach… A bit further, just let it drift into place…
SAS disabled.
What!?
No control.
No power.
Lots of monopropellant left, but I can’t rotate the barely sufficient solar panels toward Kerbol. The main probe is at full power with gigantic panels and excess fuel, but the science probe that needs to perform the final claw grab has no power. I had considered attempting to claw without separating, but it wasn’t clear the claw would extend out past the body, and the mission instructions were clear anyway.
That’s a let down. It was attached with a separator, so I can’t redock and recharge…
Ramming Speed!
Well, that got it spinning a little, but it still never pointed at the sun and was getting away from the comet.
After a second ramming attempt, it spun enough I regained control, carefully oriented it to charge at 0.01/s, and completed the mission!

[Canem]

Now that I think about it, sudden loss of power kinda adds to the realism.
Didn’t the real Rosetta mission lose power early because it sorta bounced into a dark spot on landing and couldn’t charge? Unintentional I know but hey, it kinda fits the scenario nicely.

@SirDrew

That’s a let down. It was attached with a separator, so I can’t redock and recharge…
Ramming Speed!

I think I’ve learned my lesson but twice now I made kind of a mess not realizing there’s a minimum impact speed to get the claw to grab. Turned it into a glancing blow and sending the other craft spinning. Kind of annoying considering it was a powerless craft so I couldn’t stabilize it again.

[SirDrew]

@Canem

not realizing there’s a minimum impact speed to get the claw to grab.

I knew it and still wasn’t going fast enough on the first attempt! Seemed minor after the power loss when it didn’t send me spinning [or] trigger another power loss.

@Canem

Kind of annoying considering it was a powerless craft so I couldn’t stabilize it again.

All craft have mumble quantum power mumble stabilizers. They take forever if you stare at them, but if you look away or blink while in time warp, they’ll stop even powerless craft from spinning.

[SirDrew]

Tonight I tried 1.11.1. Previously I was playing 1.11.0.
Observations

1. at 1000m a deployed mk2-R falls at about 1.7m/s
2. recovering an mk2-R which was in orbit of Mun didn’t fulfill the requirement to “Bring a vessel that was in a stable orbit of The Mun back to the surface of Kerbin”
3. What’s up with SAS in this release? Even the Stayputnik has full SAS. Oh, this: Bug #27162: SAS options do not correspond to the pilot - Kerbal Space Program - Squad Bugtracker
   

[SirDrew]

Observation 4. Back to the surface does not require recovering the vessel.

If one were to land a vessel without probe control on a mountain side, automatically cut one of two parachutes, slowly roll far down the mountainside, reach a spot where rolling slowed further, not stop, automatically cut the other parachute, start picking up speed, and explode prior to becoming recoverable… That would be considered a successful return to the surface of Kerbin from orbit of the Mun.

[Syonyk]

This sounds an oddly specific hypothetical…

I might have a house computer back at some point in the next few months, I’m sure kid[0] would love some quality KSP time!

[Canem]

Ok, so you see… I’ve had this problem. A deep space cruiser, outfitted with a Mk3 capsule, a science lab, and 6 nuclear engines. Crewed by one pilot, one scientist, and one engineer, it has completed orbital tours of Duna, Ike, and Eve.

The problem? I uh… I got it stuck… around the sun. Uh oh.

So I knew it would be tight only having about 2000dV left when leaving Eve SOI. I figured maybe it would take a couple passes to line up reasonably well with Kerbin but I could hit the SOI and return to LKO for a full refit and refuelling. Boy was I wrong.

From about 90 degrees right of Kerbin (I guess the term is Eastern Elongation?), I could hit the Kerbin SOI with about 1200dV to spare. This is fantastic, and it’ll only take…

2400dV to achieve capture. If I had made that burn it would also be on a trajectory completely out of the solar system’s orbital plane and that made it a slingshot maneuver into deep space. Nuts.

So here goes the first tanker. I used the precious little fuel left in the cruiser to re-circularize the solar orbit, leaving about 300dV left in the tank.

First, we get the tanker sorta within an AU or two.

With remarkably little RCS thrust from there I could get that intercept to less than 10km! That was never going to hold since there was still a 1300m/s speed difference to deal with but it’s getting there.

Oh man, there it is. Sooo close…

If you ever want to see Jeb alive again ya’ll need to be paying me a lot more money for solar rendezvous you jerks.

Well nevermind that. First thing, this cruiser was launched before I unlocked the Gigantor Arrays and with the science lab it was woefully underpowered. Time for a quick refit. Do your thing Bill.

Turns out, you can do EVA construction while flying, no ladders needed! Made it easy to reach the more distant components.

Monoprop refilled, fuel transferred, solar panels and batteries added. Proceed with undock.

Now for all our efforts, we now have a new fuel load of a whopping:

Did I mention this automated tanker ship launched with just under 10,000dV? Sigh… ok then. Well at least we know solar docking is possible now. Just have to do that 4 more times to get home.

[SirDrew]

This is the story of a fledgling space agency (and the backstory [and the real story]). Valuing Kerbal life, probes have orbited and landed on Mun and returned. (Also, probes are easier to provide with the necessary delta V.) [Also, the settings are on hard plus various difficulty effects enabled, so Kerbals die easier and don’t respawn.]

Having completed various maneuvers in and around Mun, a well-paying contract to flyby Minmus was accepted and completed. We’ll probably be asked to plant a flag on Mun next.

Nope! The public wanted a face for the KSP closer to home, so we arranged a crew transfer between vessels in orbit of Kerbin (hardly mentioning that this implied getting at least one Kerbal into orbit). While that cost some credits, it should allow us to go on to even bigger things. (We launched a test vessel with enough delta V it should have been able to make the trip while also demonstrating the ascent was safe before doing the same with a Kerbal.) [It also seemed like a good time to upgrade the Astronaut Complex to allow EVA in case something went wrong, and possibly get another contract for docking rather than doing that for free.]

Since we needed publicity, how about we plant a flag on Mun? Wrong again, the public wanted us to land on Minmus and return, so we were obliged to accept (and it paid well enough we could upgrade the R&D building, if we were willing to forgo a safety buffer) [and I’m only choosing mainline contracts which tend to come one at a time, so the options are limited].

As a well-run agency, we’re careful with our credits and efficient with our hardware, having not yet exceeded 30 parts in a mission. (… and haven’t upgraded the VAB to ensure we have a buffer to cover publicity stunts like that crew transfer which paid less than 6K credits!) [… and I was more urgently interested in getting things like docking, fuel cross feed, and fuel transfer available.]

Having landed on both Mun and Minmus, perhaps someone would pay us to plant a flag? Whoa! An Eve flyby and return? Let’s do it! With Kerbals! For the public! (We don’t have relays that can reach that far yet.) [Upgrading R&D would still put me rather low on credits, especially now that I’m looking at interplanetary missions and still need to upgrade the VAB at some point.]

What’s the plan for Eve? Let’s send a Pilot (otherwise we won’t be able to plan maneuvers.) A Scientist would help a lot. (We’ll need science to buy those more powerful relays once the R&D building is upgraded.) [I should probably save a Pilot and an Engineer for a rescue mission; guess that’s everyone!]

[edit: I need the R&D upgrade for fuel transfer, and stored parts count toward mass but not toward part count limit. Looks like the R&D upgrade is more urgent than the VAB upgrade.]
[edit2: I’m not actually sure if there are mainline missions to plant flags on various bodies or if I’m being promoted early. (It might have something to do with losing control of that probe but publicizing it as a gravity assist to escape Kerbin’s SOI.)]

[SirDrew]

Congratulations to Valentina and Bob! You have been selected for two round-trip tickets to Eve’s SOI.

(
Valentina is still in orbit from that transfer. The ship currently has 3946dV available. If it were fully refueled, it would have 5179dV. If an occupied command pod and heatshield were docked to that fully refueled ship, that would bring it back down to 4314dV.
)

dV map:
870 to barely escape Kerbin (this is an inefficient first step, but it allows [[us]] to figure out the timing for the second step, then combine them into one burn for efficiency)
900 to burn near an intercept with Eve
450 to setup final intercept for the flyby to leave [[them]] heading back out toward Kerbin
870 to shape [[their]] orbit roughly like Kerbin’s, [since I can’t seem to plan an intercept for the body I’m currently orbiting]
[ That last step should be roughly what I need to enter Kerbin’s SOI going slowly. If I enter going quickly but then burn low, that’ll save fuel. If I combine the first two steps, that’ll save fuel. I might need help slowing down enough to land, but if I’m captured at Kerbin a rescue can be sent. ]
Total: 3500dV including some safety margin.

[ I was planning on adding a second ship minus the extra scients bits, docking, and sending them both off with a bunch of extra dV but avoiding the fuel transfer. ]
( There was a small mishap… while typing up dV calculations, someone must have hit space in the wrong window… Valentina is now in a fully fueled ship… with 2097dV, having ejected two half-full fuel tanks. )
[ I tried tabbing away from the window and pressing “X” to try to avoid saving the lost fuel tanks. That didn’t work. I know I could have been more violent and run kill -KILL, and I could have edited the save file, but I didn’t, and I won’t. New plan: dock a second ship, still have something like 4300 dV and some backup parts in case something goes wrong.]

==========================

Update: After receiving extra experiments and fuel, Valentina and Bob are on their way! (The new ship configuration meant the Science Jr was going to be ditched first rather than last. Now it connects the two command modules. Extra fuel seemed prudent, especially with the extra mass.) Since the trip was delayed, we’ve sent Since a parts run was already necessary, some EVA experiments kits with them. (First, an Engineer was needed to move the Science Jr. Then the Engineer couldn’t move the tanks blocking the Science Jr, so another parts ship was sent.) [That ship barely made orbit, so a second parts ship was sent.]

The ship is currently orbiting Kerbin with 4014 dV available. (Extra parts mean extra mass, and fuel available was not enough to top off without taking more time to dock with a tanker in addition to the ships carrying parts and the Engineer.) As planned, the first two burns have been combined for a burn of 1016.2m/s (with a flip in the middle to ditch mass, swap control points, and activate the engine on the opposite side of the ship). This saves roughly all of the dV which would have been spent on the second burn. (It was possible to spend about 200 more dV and intercept without the next node, but the savings would have been less, and a course correction would surely have been needed anyway.)

Bob and Valentina preparing to leave Kerbin orbit:

==========================

Update, some four hundred days later: After burning to leave Kerbin orbit (~10m/s adjustment 2 minutes after initial burn), Valentina is planning nodes with 2958m/s to spend. Currently the plan is to spend ~420m/s to intercept Eve and escape with Kerbol Ap just larger than Kerbin’s Ap. That will be refined after Kerbin escape.

[SirDrew]

Update, days later: After escaping Kerbin SOI, Valentina continues to refine planning nodes. There were some adjustments after our crew swapped places to allow Valentina to better control the ship and Bob to better reach the science experiments. He still can’t reach the Science Jr without the EVA jetpack (not having the goo above the crew hatch might have helped). Current dV remaining is 2957m/s.

The current plan is to

1. burn ~430m/s to flyby Eve and leave with an Ap just over Kerbin’s but in Eve’s plane.
2. burn ~310m/s to return to Kerbin’s plane
3. burn ~300m/s to partially circularize
4. fine tune to intercept Kerbin (currently 1m/s, but that won’t last)
5. fine tune to fall deep into Kerbin’s gravity well (TBD; nodes get very uncertain this far out) and burn perhaps 600m/s to circularize (that number won’t last either)

That leaves over 1000m/s safety margin. [Good thing Kerbals are so self-sufficient!]

[I’ve been wishing there were a way to adjust the time of a node in steps like there is for the three spatial magnitudes of a node. There is! The adjustable step-size scale is m/s for space and s for time; the center circle around the 3-d axis is split with symbols for ‘<’ and ‘>’. In addition to -/+ full orbit buttons I was aware of, the center is a pair of step-node-time buttons!]

==========================

Update some hundred days later: 2529m/s remaining and on target for the flyby. Next step, collect some science!

==========================

Update some scores of days later: Valentina and Bob are flying by Eve! Science is being collected. Escape is days away! (Something was funky with the controls until Bob let go, but Valentina got it under control, allowing Bob to collect science and return to the cabin.)

==========================

Update some scores of days later: Just another burn on the long road home, this time ~310m/s. 2218m/s remaining. The next burn is planned for 84.0m/s in 73d1h. Depending on accuracy, that might reach Kerbin SOI. Either way, a correction is expected somewhat over 4 years later. (Valentina is so patient!)

==========================

Update 73d1h and 84m/s later: Current dV is 2134m/s. Kerbin Encounter in 4y97d5h with no intervention. The current plan is to spend 73.5m/s to adjust deep into Kerbin’s SOI in 4y54d, burn about 200m/s inside Mun’s orbit, ditch over 300m/s dV in extra fuel tanks (no need to pollute Kerbin’s SOI when Kerbol is so much larger), burn about 700m/s to reach Kerbin orbit with Pe ~180km and Ap ~800km. That should leave about 800m/s to figure out how to land this thing. (Valentina thinks this is Fantastic! Bob was ready to go home after Eve but has to wait over four more YEARS until Valentina does anything more to get him there!)

[Syonyk]

@SirDrew

…ditch over 300m/s dV in extra fuel tanks…

o.O Ditch… dV… on purpose?

You know you can destroy debris in the tracking center, right?

[SirDrew]

@Syonyk I have enough extra dV I might try a Minmus landing. If not, maybe a Minmus or Mun flyby at least. I think that would be enough to level both of them from 0 to 3 in one go.

==========================

Update: Ditching partially full fuel tanks seems like a waste (especially when there is Science and Experience to be had). There are even fuel tankers hanging out in LKO (and an Engineer to hook up the fuel lines). Valentina could plan more nodes. Bob could collect more Science.

Here is one plan being considered:
73.5m/s radially => 391,304m Pe above Kerbin
1.1m/s fine-tune encounter to place Descending Node WRT Minmus near Kerbin Pe and further lower Pe
~190m/s to achieve capture and drop Ap to just above Minmus
~10m/s to adjust to Minmus plane
~230m/s to nearly circularize near Minmus
That leaves ~1500m/s to land on Minmus, return to orbit, and figure out how to get home. The landing may include hauling 2 empty fuel tanks to serve as landing legs.

Here is another:
73.5m/s radially => 391,304m Pe above Kerbin
~1m/s fine-tune encounter to further lower Pe and possibly tweak plane
~1100m/s to circularize around 110km
dock with one of the fuel tankers and continue to Minmus or Mun

[SirDrew]

Update: Here’s the new plan which gives Valentina more burns to execute and Bob more Science to collect (and both of them enough experience to get promoted from 0 to 3 stars) [and allows me to ditch the tanks after using them to land on Minmus. I /can/ just destroy debris, but I /prefer/ to plan the missions where it naturally falls into a gravity well.]:

1. 26m/s mostly radially => 83,308m Pe above Kerbin and Decending Node WRT Minmus near Kerbin Pe (SOMETHING happens in 3y422d rather than 4y54d!)
2. likely some fine-tuning
3. 191m/s to achieve capture and drop Ap to just above Minmus
4. ~150m/s to circularize enough to avoid an accidental Mun encounter (about 3m/s of that to change to the Minmus plane, although that’s not entirely necessary), and possibly setup a Minmus encounter
5. ~1m/s to fine-tune the Minmus encounter
6. ~70m/s to achieve roughly circular orbit ~48km over Minmus (More Science!)

That leaves ~1700m/s to land on Minmus (More Science AND Another Landing!), return to orbit, and figure out how to get home. That leaves ~200m/s in the fuel tanks before beginning the Minmus de-orbit.

==========================

Update: [4y takes awhile, even at maximum warp] Prepared to burn. Current dV: 2134m/s.

==========================

Update: The burn went well; overshot a touch and corrected.
Current dV: 2107m/s
Kerbin Pe 87,479m
Descending Node WRT Minmus: -8.1 degrees and aligned with Kerbin Pe

The plan is still to spend 191m/s to get Ap just above Minmus.

==========================

Update: Orbiting Kerbin! That’s almost like being home, except we’re flying past at over 3100m/s.
Current dV: 1916m/s
Pe: 87,494m
Ap: 49,397,156m
8.1 degrees from the plane of Minmus

This was NOT in the original mission plan!

It looks like we’ll spend a touch over to 170m/s and 70m/s on the next two burns, but we’ll end up in a ~20km orbit rather than a ~48km orbit.

…

~170m/s spent.
Current dV: 1745m/s
Minmus Encounter 38d3h1m

…

Current dV: 1676m/s
Minmus orbit: 23,716m-24,916m
Inclination 85.3 degrees

Hey Bob, where would you like to do some Science? (Preferably somewhere flat – we have no landing struts. 175m/s left in the tanks we plan to land on.) We’ll spend a little dV to keep the tanks through the landing, but that’ll be much more stable than landing on the Terrier (let’s not disable gimble in this ship).

…

[ Every time Bob steps out, the ship bumps around enough to change the orbit. Weird, but I didn’t plan on going for Minmus when leaving Kerbin! ]

[SirDrew]

Landing on Minmus, orbiting, and returning to Kerbin was rather uneventful. There was initially some concern about deorbiting the command module docked to the science Jr docked to the command module, but the undocking force was not enough to disturb the Pe too much when facing normal, and there was plenty of dV remaining to re-dock and make another attempt anyway.

Landing provided 810.8 science points (not counting any already transmitted or any mission rewards) and 6 stars worth of experience.