Craft deleted around 13km above Kerbin

[ZekerMarco]

I'm trying to make a recoverable rocket. It's going well, except that my recoverable sideboosters just disappear when about 13 km above Kerbin.

The craft consists of three identical boosters, two to the side of the center one. The first two are separated at about 10 km. I then quickly switch to them, activate the aerobrakes and parachutes and then switch to the actual rocket again.

However, while flying the rocket (without time warping), I noticed that my boosters just disappear from the map at about 13 km above the surface. I have no idea why this occurs because when I manually fly them they work just fine. Any idea why this happens and how to fix it?

Edited September 25, 2020 by ZekerMarco

[Entropian]

There's a "death zone" there for non-player-controlled craft.  This is to prevent suborbital "orbits."  Mods such as FMRS let you jump back in time to recover boosters:

 

[FloppyRocket]

Your side boosters were deleted as sub-orbital debris. Only craft that you're flying are persistent.

[jimmymcgoochie]

There’s a cutoff for all craft that means they get deleted if they go below a certain altitude- I think the game is pretending that they either burnt up or crashed into the surface. Some mods like FMRS or Stage Recovery can still salvage those vessels or debris, either by rewinding time and letting you fly them (FMRS) or simulating their descent with parachutes and/or a powered landing (SR), but the stock game doesn’t let you do this.

[king of nowhere]

to be more exact, when you are in the atmosphere, crafts farther than 20 or 25 km from you are deleted. so, your boosters disappear when reaching that distance.

there are mods to avoid it. personally, i started launching bigger rockets that can go directly to orbit with the first stage when i want to recover them.

[Entropian]

6 hours ago, king of nowhere said:

to be more exact, when you are in the atmosphere, crafts farther than 20 or 25 km from you are deleted.

I disagree.  Usually by then the other craft falls into the death zone, but there isn't a distance away from the active craft that everything else in-atmo disappears.

[ZekerMarco]

Thanks for all the replies, that's a bummer. I'll try the FMRS mod.