Debris and Reusable Space Programs

[NEBx]

Hey all,

I don't know how to do this more succinctly so I apologise but I will clearly label each section for your convenience.

 

BACKGROUND

It's my understanding that there is an umbrella system to dealing with debris in an attempt to encourage more efficient rendering and physics calculations in game.  Basically the rules are that debris is over 2km from the main craft in atmosphere or on a suborbital trajectory then it is simply removed from the game.  EDIT: Debris 25km from main craft <25,000m altitude = auto-deleted

So in the case of recovering a spent stage from a launch, you would need to switch focus to the debris once ejected and stay focused on it till it touches down.  Then if you wanted to actually get returned funds, it must have a control capable part attached (usually a probe body).

 

I can't find a way around this and tutorials I have seen have been from a couple years back before the new aerodynamics system, so simply having a steep suborbital trajectory doesn't work so well for the ejected stage simply burns up.  You might be able to help this with late tech larger heat shields but you're kind of stuck early in your career.

 

QUESTIONS (read dot points below questions for further explanation)

What is the point of having settings in the menu like "Max Persistent Debris" and "Tidy up debris cluttering KSC"?

• It seems to me that the majority of debris will be generated by launch vehicles and spent stages, which are likely to be left in atmosphere or a suborbital trajectory and thus they are going to be cleaned up by this umbrella system anyway.

 

Could this umbrella system be a tweak-able option like the 2 listed above?

• Leave this option to the discretion of the user depending on the capabilities of their gaming system.

 

Any ideas on how to recover stages early in career?

 

CONCLUSION

It just seems silly to me that you need to leave your craft effectively uncontrolled for the sake of guiding 'debris' back to the surface.

Although I understand the idea of making sure the game is running as efficiently as possible, it seems to me that the 2 tweak-able options in the settings are there for that purpose but allow more user control.

This umbrella system just seems more restrictive to me but please share your thoughts and ideas.

Edited November 30, 2016 by NEBx

[FancyMouse]

The "background" don't look quite correct. What I understand, ships (regardless of being debris or not) of distance >2.25km (or ~20km in atmosphere) are only unloaded from physics - this process doesn't deal with deletion.

The unloaded ships (again regardless of being debris or not) will get deleted when they are flying but too low (a pre-defined altitude per body, ~25km around Kerbin).

And then for those settings that deal with debris - debris (and only debris) are unconditionally removed when there are too many.

 

So basically just try somehow to let the spent stage stay high enough from unloading until you finish circularizing payload orbit, you should be able to go back to it.

[NEBx]

20 minutes ago, FancyMouse said:

And then for those settings that deal with debris - debris (and only debris) are unconditionally removed when there are too many.

Thanks for that FancyMouse,

My debris appears to disappear regardless of my settings, including the filtering within the tracking station.

Also if craft are only unloaded from physics why can't I switch back to them even in map view (well they don't even show up) is that normal?

 

Cheers!

[FancyMouse]

Just now, NEBx said:

My debris appears to disappear regardless of my settings, including the filtering within the tracking station.

I remember that the number in max debris setting really means the total number of ships, i.e. delete debris if the total number of ships+debris exceed that value. At least back a few versions it was so. Not sure if it got changed.

Other than that - I don't know. I haven't recover rocket stages myself, but I see quite often that my spent stage goes suborbital for quite a while (separated in atmosphere, marked as debris, orbit visible) and get deleted after I circularize my payload.

[bewing]

FancyMouse basically has it right.

* Anything that is not in focus, and is not on the surface, and is not in physics range of your current vessel, and is less than the autodeletion altitude (25km on Kerbin, lower on smaller CBs) gets autodeleted. Including craft with Kerbals in them.

* Anything that is landed on Kerbin can be recovered for funds -- it doesn't need to be controllable.

* The "tidying" function recovers any parts that are on the runway or launchpad for funds. This includes launch clamps, bits of crashed vehicles, and anything that you launch low enough that it can land with a parachute.

* This has nothing to do with the "Max Debris" setting.

* To recover a stage, you can use the Stage Recovery Mod, or you have to switch focus between your craft and your spent stage until that spent stage is on the ground. You can either get your upper stage into orbit first, then switch focus (but you have to lob your spent stage very high for that to work), or you have to have so much TWR that you can lob your upper stage really high while you land the spent stage, and then switch focus back to the upper stage. Your problem with not being able to see your spent stages is probably because you have debris "turned off" in map view -- but it is there. So no, if your spent stages really do vanish somehow, that is not normal.

* The problem is that the physics calculations in atmosphere are "expensive" computationally. So KSP only models one small area of the universe. It can't model the physics of many objects reentering the atmosphere simultaneously.

 

Edited November 30, 2016 by bewing

[NEBx]

1 hour ago, bewing said:

* The problem is that the physics calculations in atmosphere are "expensive" computationally. So KSP only models one small area of the universe. It can't model the physics of many objects reentering the atmosphere simultaneously.

I'm sure I remember it used to do this but perhaps with all the changes introduced to the game since then it is just too much.  Still I wish it could at least be a tweak-able option so those with higher end machines could do this.

 

Well thanks a bunch guys!

I have tested everything you have mentioned and you're absolutely right.  It seems that as long as you get those ejected stages above 25km altitude you can switch back easily enough to guide them back to the surface however you would still want a probe so you can pop your chutes at the right time.

Any debris that does not have a probe on it is recovered for funds but it does not give you a report like a normal flight.  I guess that's where I was getting tripped up.

Cheers

 

Edited November 30, 2016 by NEBx

[bewing]

If you activate the chutes before you separate the stage, they will automatically wait to open until they are at a safe speed and altitude. Technically, you can activate them at the same time as the stage separation, but sometimes there have been timing issues that make that not work occasionally.

But I basically agree. It would be nice if KSP would do atmospheric physics modeling for everything on a toggle, perhaps, so you could switch it on and off when you knew something important was going to be reentering.