When is debris not debris?

[Johnny Wishbone]

I'm including the full story here because some people like reading that stuff. For the tl;dr crowd, skip to the bottom.

Last night, playing a career game. Still relatively early in the career, so I only have about half the tech tree unlocked. Got a contract to rescue a Kerbal marooned on the Mun. Figure I'll do a quick and dirty rescue mission. Throw together a lander craft, put in a Kerbal that needs Mun landing experience, and send it to the Mun. After landing near the stranded Kerbal (close to the Mun south pole), I realize that I don't have enough delta-v left to even get into Mun orbit. Thankfully, I have a docking port on the rescue craft, so I figure I'll do the Kerbal thing and send a rescue mission to rescue my rescue mission. Throw together another rescue craft, put in a 3 kerbal crew (need experience) and send it to the Mun. Get it into the appropriate orbit and then launch rescue1 from Mun surface into a high, suborbital trajectory. Timed it so rescue2 craft would intersect, and then I burn a ton of fuel getting them to rendezvous and dock (as they are both hurtling towards the Mun surface). Burn a ton more fuel boosting the now docked craft back into Mun orbit and realize that I now don't have enough fuel to get either craft back to Kerbin. What to do now? Yep....rescue mission for my rescue mission for my rescue mission.

This time, I just build a remote controlled fuel tanker. Slap a probe core on a fuel tank, add an engine, some RCS ports (and fuel) and a couple docking ports on opposite sides of the fuel can. Launch that into LKO, send it out to the Mun, get it into the right orbit, and rendezvous with the docked together rescue1 and rescue2 craft. Then I undock those two craft from each other and dock each one to a port on the fuel tanker. Hooray! I now have plenty of fuel to get both rescue craft home to Kerbin and can leave the fuel tanker floating around the Mun for future missions. I transfer enough fuel to rescue1 to get it back to Kerbin, undock it, and send it back. Re-entry is cool and mission successful.

Then I get to thinking, why send rescue2 back? I got tons of fuel in it now; why not send it to Minmus and see if I can pick up a few contracts with that? But first, lets get rid of some clutter. All these launches have been terribly inefficient and I've left a lot of junk in space. Lets go to the tracking station, sort by debris only, and terminate all the stuff labeled and classified as "debris". So I do this, and then go looking for my rescue2 craft (which I left still docked to the fuel tanker). Hmmm....not there. Not listed as a ship, not listed as a probe, it's gone. Check the astronaut complex and, sure enough, 3 dead Kerbals; KIA. Really??? Apparently, the tracking station classified (and labeled it) as debris despite the fact there was a probe core on the tanker, and a manned ship docked to it.

Sigh. Pouring out one for my dead homies....

TL;DR - A fuel tanker with a permanently attached probe core (and therefore a 'probe'), and a manned ship docked to a docking port on the fuel tanker was labeled and classified as 'debris' and not as a 'probe' or as a 'craft' by the tracking station. Therefore, when I terminated all 'debris' via the tracking station, I killed an entire crew. Awesome.

[More Boosters]

Why would you attempt a Sun rescue mission? Those take years and aren't worth it!

I never miss a Minmus rescue however.

[Archgeek]

When you forget to pop a probe core onto the transfer vehicle for your single-launch to Laythe craft, leaving your lander to dock very carefully.

[RogalDorn]

Why would you attempt a Sun rescue mission? Those take years and aren't worth it!

I never miss a Minmus rescue however.

Never Leave a Kerbal Behind!!!

[ClF3]

I've noticed a few times that after hitting the confirm button in the tracking station, another one immediately popped up. I'm not sure if that's another confirmation for the same vesselID, or if somehow KSP cycles to the next VesselID in the list and wants to nuke that one as well (I haven't ever noticed any missing ships or crews in this way). This being related to some kind of bug is of course pure speculation from my part.

I've read there's a configuration option that limits the maximum amount of debris. It's set quite high by default, but you could lower that to automate these cleanup actions (of course this does rely on an accurate classification as debris by the game)

[ZentroCatson]

Well, since that was a tracking station flaw, you could just .cfg edit those three back from the dead. The best solution to this is to just not terminate debris. Afterwards its fun seeing how much debris flies around in orbits around various bodies.

[Aragosnat]

Hum. Odd. Only stuff that don't have crews or probes should be auto-labed debris. True you can when rename it turn it to debris. One of those things you need to make sure it has the right icon as well as no passangers. But, yeah. I have deleted crew by mistake.

Sidenote: On the title. When is debris not debris.

A) When it hits your craft. Then it is a balistic missile.

When it is on a sub-orbital trajectory. Then it is a meteor and any thing that survives is a meteorite.

[Superfluous J]

I was going to say, "when it's a jar." But then I decided not to.

Perfect reason to not ever delete debris.

[passman]

next you should try a rescue mission without docking ports

[Windspren]

Why would you attempt a Sun rescue mission? Those take years and aren't worth it!

I never miss a Minmus rescue however.

Where does it say anything about a sun rescue mission? Did you even read it?

[PB666]

Never Leave a Kerbal Behind!!!

No, no, you send the male kerbals to Eve and tell them Eve needs men, and the female kerbals to Duna and tell them that Duna needs females. The Kerbals will never know the wiser and think they have a new home. The dumb ones you send to Jool and tell them gravitons need mates also. Laythe you send all those who profess SSTO theory.

[The Destroyer]

Never Leave a Kerbal Behind!!!

My first solar rescue was intense, Jeb was stuck in Solar-Near duna, and he was running out of life support. He would die in a year.

After hasty launching and rendevousing (little harder out here...) I got him with only a few months to spare

[Nich]

This is why I love Kerbal alarms it automatically makes backups of the persistence file when you switch ships. I have no issues reverting in this case. I do however have done this before so I no longer delete debris. I just hide it in the tracking station so it doesn't clutter up my map. Persoanlly if you cant revert or restore I would cfg them back and hyperedit them back to the Mun. Dieing to a debris delete is just dumb I wish it actually checked for crew before issuing the are you sure message.

[Wiseman]

I think the actual bug here lies in the way that the game handles splitting ships up after docking and undocking. My understanding about the way KSP works is that when two ships dock together, you don't have two ships anymore, you have ONE ship, and a couple of lines of text in the ship's persistence file that remember things like the name and classification. Then when you undock, it splits them into two ships again without actually knowing anything about the ship that once existed as a whole vessel - it just snaps the Legos apart at the docking node, and rebuilds the ship from there, since what if you docked ANOTHER thing to the second ship, etc etc. My assumption is that it attempts to read the old name and classification from the previous root part / command part, but that's just me speculating.

The process seems to work mostly okay for the actual physical separation of the vessels, but the naming and vessel classifications are a crapshoot. It seems to me that KSP has a hard time dynamically figuring out what a vessel should be named and classified as, especially if you glom together a bunch of different ships together and then break them off asymmetrically. If you have a fuel tank or something as the root part of a vessel, that seems to exacerbate the issue.

[keeper]

I always make a habit of re-naming the craft after seperation/undocking. Its more of a procedural chore - to prevent mix ups like this from happening.

I too have deleted ships totally unintentionally. That list can get boggling. But i put it down to my own human error. I must have just either clicked the wrong thing, or not checked what it was called, or expecting what I delete to be some other part...

Now I jump to every object i'm about to delete before i delete it. I cant "just delete" some object without first being certain I know what it is. Infact now I delete things so rarely I make a thing over it because things don't normally just vanish. I havn't looked at my debris list in a while. No doubt its more or less empty.

I imagine, if i deleted a ship - then everything docked/attached any-how would also go.

When docking/undocking the names sometimes get remembered, but other times i later find my landers end up being called things like "minmus refuel station" or "science lab 1" when it should be a mun lander or something.

Had a probe core, had kerbals in it, had power, antena, dock - and was listed as debris? Are you sure?

Did you set it to debris? When re naming? lol

[Hobbes Novakoff]

Wait, there's an option to delete all debris? Say what?

[keeper]

Actually I've just looked at my debris screen, all my ships are at the bottom of that list omg ... none of them are actually debris. That is sickening.

[Superfluous J]

Wait, there's an option to delete all debris? Say what?

There's an option to set persistent debris to 0. I've a friend that occasionally sets it, lets all the debris delete, and then sets it back to 250 or whatever. I assumed that's what the OP did.

[AbacusWizard]

I used to just delete debris from the tracking station, but in this version (I usually start a new career game with each major release) I decided not to do that. Instead, I've been trying to minimize orbital debris from launches (jettisoning empty or nearly-empty stages while still sub-orbital whenever possible), and using a small two-seat ship with a harpoon gun (thanks, KIS/KAS!) to tow any existing debris onto sub-orbital trajectories for disposal. It's been an interesting challenge and a lot of fun; I've reduced the debris count from nearly a hundred to about 20; and I've become much better at arranging rendezvous with little ∆v cost.

[Johnny Wishbone]

Had a probe core, had kerbals in it, had power, antena, dock - and was listed as debris? Are you sure?

Did you set it to debris? When re naming? lol

Yes, that's correct. The fuel tanker had a probe core on it and 2 docking ports. my rescue craft were manned and docked to the docking ports. I did not rename anything. I simply undocked rescue1, flew it home, recovered it and went to the tracking station. sorted out everything but debris (assuming that something with a probe core and a manned capsule would not be classified as debris) and started terminating. When I went back to look for my rescue2/fuel tanker craft, it was not there and the crew was listed as KIA.

There's an option to set persistent debris to 0. I've a friend that occasionally sets it, lets all the debris delete, and then sets it back to 250 or whatever. I assumed that's what the OP did.

No. I apologize for any confusion caused by the way I phrased things. I did not terminate all debris at once and don't know of a way to do it. I sorted everything out of the tracking station except debris and went through one by one terminating debris. I wasn't really paying attention to everything I was terminating because I assumed a manned craft with a probe core would not be classified as debris. Apparently it was and I terminated it along with the rest of the junk. I phrased it the way I did for the sake of brevity and did not mean to imply there is a way to blow away everything with one click.

- - - Updated - - -

For further clarification on this issue:

1) I did not name or rename any of the vessels involved in this story. I'm using the names 'rescue1' and 'rescue2' for the sake of the reader to keep track of what I was doing to what. All vessels were actually using the default name of "Untitled Space Craft".

2) When I went into the tracking station and sorted out everything but debris, the list of tracked objects on the left side contained everything labeled as "Untitled Space Craft debris". I went through one by one and terminated these objects assuming my manned craft docked to another craft with a probe core would not be classified as debris and therefore show up in that list.

What I think happened is what Wiseman and keeper were getting at: when I docked the two rescue craft to the fuel tanker (all three being named "Untitled Space Craft"), it kept that name for the resulting ship. When I undocked the first craft (what I'm calling rescue1 in the story), it kept the "Untitled Space Craft" name and the other ship (rescue2 docked to the fuel tanker) must have automatically renamed "Untitled Space Craft debris" and classified as debris despite having a probe core and a manned capsule. So when I started terminating debris in the tracking station, I blew away that ship.

In the end, it does come down to me not thoroughly checking everything I was terminating and making assumptions (you know what they say about that...). Lesson learned. But still, I'm confused how a manned ship can be classified as debris.

[richfiles]

When i want to terminate stuff, I manually switch my vessel to debris, undock the dead item, and then reset my original vessel to whatever it was (probe, station, base, crewed vessel, etc). This has the effect of actually manually marking discarded parts as debris. Furthermore, I tend to "fly" all my debris, before deletion if I am unsure as to it's nature.

Efficient??? NAW!!!

Safe??? My KIA list is EMPTY!

Why??? NEVER trust KSP tracking station... It harbors the spirit of the unholy offspring of Danny and the Kraken, awaiting the macabre sacrifice of the little green doods you love!

I kid, I kid!

[Sharpy]

Never Leave a Kerbal Behind!!!

They sent her on retrograde Sun orbit, they bring her back. And they want me to bring the mk3 cockpit she was in as well.