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Deorbiting Spent Stages in Early Career Mode?


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I know you can go to the tracking station and remove debris, but that always strikes me as slightly cheating. It's like they just stop tracking the debris, but it would still "really" be there.

I've read numerous posts mentioning deorbiting debris, but how do you achieve that early in career mode? I don't have seperons to slow the stage or inline probe cores that would allow me to remotely control the stage after separation. Is there something I'm missing, or would I have to wait until I've got the Claw and build a small stage to dock with and deorbit debris?

Edited by Clipperride
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For boost stages, design the rocket so that they're staged off before your PE is out of the atmosphere. Design the next stage (for LKO-only missions) so that you use it for your de-orbit burn as well.

For Mun/Minmus missions, burn so that you'll hit them, then stage off the transfer stage, and adjust again so you have a PE. Or keep the xfer stage long enough to get into a sub-orbital trajectory before you dump them, then either land or circularize again.

Some amount of debris is going to be inevitable unless you spend a lot of effort. It could just be left up there until you have the tech to go get it.

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Without a method of control or the claw, there's nothing you can do to discarded stages in orbit except terminate them or leave them. I suppose if you crashed into one hard enough you might get it to hit the atmosphere and re-enter, but then you'd likely have more debris...

In the early career, if you're concerned about orbital debris, you'll just need to design your rockets to discard the main stage before establishing orbit. Anything you take in to orbit, you'll need to take back down with you, or at least push it's periapsis below 25k before ditching it. Objects on rails below 25k are destroyed by the game.

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I know you can go to the tracking station and remove debris, but that always strikes me as slightly cheating.

Don't feel too bad about; IRL air drag eventually takes almost everything in LEO down. In my career save I have zero qualms about removing any debris with an Ap below 70 km (after all, I could make each one the active vessel and then wait... but I have a life).

You could always go back and get it with a claw-equipped ship later in your career...

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It's generally not worth the bother to go physically clean them up, unless you want to do that as a challenge. ;)

Easiest solution: Just ignore it and let the debris pile up. It's not like it's really hurting anything, they occupy minimal system resources since they're running on rails unless you get right up close to one. The game will start auto-deleting them if they start to get ridiculously numerous.

Next-easiest solution: Arrange your flights as SpeedDaemon suggests, so that whenever you cast off debris, it's already on a suborbital or impact trajectory.

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Yes, I definitely do what SpeedDaemon suggests as well. It takes a bit more planning, but it's not difficult at all for Kerbin, Mun and Minmus missions. It leads to pretty simple and effective designs.

Staging just before final circularization is a perfect time to switch from high TWR engines to small, efficient vacuum engines.

I still leave some debris here and there (usually for interplanetary missions it's hard to clean all the stages), but it's quite satisfying to keep LKO nice and clean.

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Clipperride,

I agree with the others here. The easiest way to deorbit debris is to not leave it in orbit in the first place.

Any stage that is boosting another stage to orbit is ditched just before circularization when the Pe is still in atmosphere.

Any stage that is used to place other payloads in a highly- eccentric insertion will have enough DV left over to do a deorbit retroburn. Usually with a recovery package so it can be recovered intact.

It's not difficult to keep LKO litter- free. Just a little additional planning.

Best,

-Slashy

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Clipperride,

This is most easily done through planning. how I do this uses Kerbal engineer Redux and a 3 stage rocket system. The first stage is easy to keep out of orbit, as it is the acceleration stage and it burns out by about 20 km. the second stage takes a little planning to keep it on a trajectory to re-enter kerbins atmosphere. I've found that a just 1.0 TWR on the 2nd stage at 20km, with a total of 4000 m/s vaccuum dv between stage 1 and 2 gets the final stage to around a 100x25 orbit (sometimes I have to ditch the 2nd stage before all fuel is used to ensure it re-enters). The 3rd stage stays with the payload either into orbit, or on the exit trajectory for interplanetary missions.

Similar strategies work for the Mun and Minmus, by separating the transfer stage on an path that collides with the body you are visiting, and using the return stage for the small maneuver to avoid the collision, and the circularization burn around the Mun or Minmus (plus the return)

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I just ignore it - I'm far enough along now that I could de-orbit it, but have decided it's not worth the time to do it. As in I have a small spaceplane, with a small grabber probe, that could re-enter each one. But I find a launch and rendezvous takes around 45min-1hr of real time (which is fine for a recover/rescue, but not for my own debris). I haven't figured a way that I could de-orbit them in groups etc, not sure I could make something with enough dv to change planes/orbits enough to collect more than 1 or 2 a time anyway. It'd be pretty expensive, and the only return you'd get is the recovery price, assuming you're attaching a parachute to it.

That said, the persistent debris in my game set to the default (is it 120 or 250?). Last check showed around 65 items - but that includes a couple of too hard landings on the Mun), but I'm starting to notice the occasional item coming quite close to my launches (under 50km) as I tend to launch to a similar parking orbit (between 75-100km). So I'm now doing what people mentioned above build it so a stage is dumped before circularising, or setup so it's going to hit the mun or minmus. For further out planets, I don't think it's very likely to be a problem for a stage to be left in a random Kerbol orbit.

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I'm usually lazy and set the "Max Persistent Debris" to zero. Because I see absolutely no purpose for having it up there, and the more CPU cycles for physics simulation on useful parts, the better.

Hmm, beware of that, I already had a full functional vehicle (with probe core, fuel and power) qualified as debris, while the debris part was qualified as probe...

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I found that setting up rockets to stage without debris is easier later in the game with more fuel tank and engine options. That being said, I wasn't above editing the save file to make the orbits of my debris easier to get to and thus remove. Like Warzouz, I had a piece of debris that was incorrectly identified as a probe so I had to go in and change that anyway.

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Several options that I use:

* Stage before orbiting.

* Boost to orbit, then retros on stage separation. Usually sepratrons, but I sometimes use reversed (and tilted to get spin) 24-77s by staging them one step before separation, and using whatever leftover fuel I have in my booster to deorbit it. Don't forget to deactivate the main booster engine(s), though!

* Add a cheap pod and some batteries to the discarded stage, deorbit with booster engine. Worst case, if lacking RCS or sufficient reaction wheels, deorbit half an orbit later when facing retrograde. Main challenge here is a pod 90 degrees to the engines, if you have to build it that way.

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One thing you can do for higher orbits...

-Don't circularize in low orbit right away. On launch, keep burning the lower booster until you apoapsis is as high as you need it (say the orbit of the Mun or whatever) before you kick it off. You can even use it to raise your periapsis to 0 km (I actually will raised it <60 km, but if forget if I check to make sure the game remembers to let it burn up) before kicking it off.

-Even if you have circularized in LKO, you can use it to raise the apoapsis for a higher orbit. Then just wait until you get to the apoapsis for the new orbit. A relatively small burn (assuming the new apo is high enough) will drop the peri to let you kick off the booster, and then you just do another small burn right away to raise it back up again (or, more likely, circularize).

This doesn't help very early in career, but in "early-mid" career, when you have probe cores you can put in the middle of the stack, you can leave a probe core, 4 solar panels, and a little bit of fuel, and then let it deorbit itself.

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In early career you can push debris into sub-orbit using engine exhaust. When I pick up rescues I usually manoeuvre my ship in front of the empty pods pointing to 90° and give them a blast at full throttle. It's usually enough to put their periapsis deep into atmosphere so the same could be done for random debris, just make sure you're doing the de-orbit kick close to apoapsis.

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I put a probe core and battery inside a service bay, hide a heat shield in my faring, strap some chutes on the side, and then use it as a recoverable orbital maneuvering stage

I did that for a while, then I realized upside down sepatrons fired when decoupling will deorbit most final stages from 100km or less (possibly more with enough of them) a lot cheaper and lighter. Just make sure your craft is pointed prograde, so the sepatrons end up burning retro and put the sepatrons near the bottom so they pull rather than push (which may cause it to spin out of control).

However, early career (as the OP suggests) I just plan ahead in my staging so the final stage actually finishes with 25km periapsis rather than orbit and then the engine on the payload will finish on it's own. It makes it a little harder to plan your payload than the sepatrons, but it works.

I play with StageRecovery so I try to bring everything I can back.

Edited by Alshain
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I'm surprised that no one has mentioned this method. When I have to do rescue missions in lko I make the kerbal being rescued push the debris they just exited retrograde to deorbit it before letting them enter the rescue ship. I hope it gives them a sense of closure to burn up the device that they were trapped in. :P

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I'm surprised that no one has mentioned this method. When I have to do rescue missions in lko I make the kerbal being rescued push the debris they just exited retrograde to deorbit it before letting them enter the rescue ship. I hope it gives them a sense of closure to burn up the device that they were trapped in. :P
Once upon a time, I had a kerbonaut that I was trying to return from Minmus, but ended up with my Pe just barely out of the atmosphere. I needed, literally, 10 m/s dV in order to get my Pe under 70km. So Jeb (or whoever it was) had to get out and push. Let me tell you, it was tricky trying to keep the capsule from spinning too much. Probably took half an hour of careful EVA in order to get things lined up.
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I used to try and de orbit trash, but it ends up being a chore so I just delete it. IRL wouldn't orbital decay cause the junk to over time de orbit anyways? At least that's my excuse.

It depends on the orbit, but yes. Anything in orbit will decay... eventually. But in a higher orbit it could take thousands of years. There is some interesting info in

on that subject.
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