[1.12.*] Deadly Reentry v7.9.0 The Barbie Edition, Aug 5th, 2021

[jordanjay29]

You might want to take densityExponent even higher. Back to 0.85

or try RSS shields. I'm still trying to see what's best for stock but I'm not going to be very responsive for awhile as my DSL modem is ailing and I'm awaiting a new one. On my iPhone right now.

Eww. Hope the situation improves and you don't have to switch over to (dun, dun, dun) cable.

[Starwaster]

Eww. Hope the situation improves and you don't have to switch over to (dun, dun, dun) cable.

We don't have cable available here. Good news or bad? Who knows. At least I won't wake up in a roadside ditch.

[Motokid600]

Startwaster I had to up the density exponent to .85 on RSS as well. Its better, but there are still extreme heat effects with a twr of 1.07 on the pad. Now thats with a Mercury replica so my max twr is around 6 so that can't help. But even on larger rockets with 3.5 max twr I still get heating effects. The only way to counter it is to fly an unusually steep trajectory.

[Starwaster]

Startwaster I had to up the density exponent to .85 on RSS as well. Its better, but there are still extreme heat effects with a twr of 1.07 on the pad. Now thats with a Mercury replica so my max twr is around 6 so that can't help. But even on larger rockets with 3.5 max twr I still get heating effects. The only way to counter it is to fly an unusually steep trajectory.

thanks for the feedback.

Can you give numbers on the heat experienced?

[Athlonic]

@Athlonic, please sir, how do you determine the re-entry angle?

While I do not want a risk free re-entry, having to be a one Kerbal space program begs for a little lee way. IRL there would be a mission control and many highly educated Kerbals to advise the ship.

@ anyone who can tell, Could a red, yellow and green light be added to the context menu to advise us if re-entry angle is predicted to exceed ablative value of heat shield?

I have absolutely no clue about how to predict re-entry angle.

The old mod "Re-entry Heat" I mentioned had this little popup windows providing these info :

It is a (very) old screenshot, don't look at actual altitude and explosions, this popup windows displayed as soon as you trajectory would make you re-enter.

Maybe someone can bring this back, Starwaster ?

This mod used this chart by the way, actually best re-entry angle was around 20° when entering at 70km :

Maybe we can ask PakledHostage if he still have the source code somewhere ?

original thread : http://forum.kerbalspaceprogram.com/threads/21050-0-17-Re-entry-Heat-Module-and-Mk-1-Pod-Heat-Shields

[biohazard15]

Well, I've tried to land on Eve. Result: burned up regardless of anything. Didn't tried 6.25m heatshield, though; I think it might help those who play with FAR\NEAR - it will act as a giant air brake.

Anyway, I'm back to 5.2 until all this mess is sorted out.

[John FX]

On Kerbin, man. On Kerbin.

My speed was about 3000 m\s - the usual for Minmus free return.

From my testing you can reenter from Minmus with a Pe of 0km with a MK 1-2 pod and a heatshield for a MK1-2 pod at entry speeds of 3km/s+.

It crackles a bit and gets hot after the ablative has gone but you can survive.

I think for interplanetary, the inflatable active heatshield may be necessary now.

EDIT : Realchutes are not experiencing heat. In effect they are the ultimate heatshield.

EDIT 2 : What are the units that these entries in the .cfg refer to?

crewGWarn = 450000 // when G damage reaches this level, warn the player

crewGLimit = 900000 // when G damage reaches this level, start killing crew

Surely that`s not nearly a million G?

Edited October 6, 2014 by John FX

[LuciferWolfgang]

Well.... I updated without checking the forum for the change in difficulty. Poor Jeb......

Perhaps the settings are too high. I actually like that its more difficult... but this may call for more options or upgrades when it comes to heatshields.... especially when landing on Eve.

Deadly Re-entry tech tree anyone? =D

[biohazard15]

Well.... I updated without checking the forum for the change in difficulty. Poor Jeb......

Perhaps the settings are too high. I actually like that its more difficult... but this may call for more options or upgrades when it comes to heatshields.... especially when landing on Eve.

Deadly Re-entry tech tree anyone? =D

The trouble here (updating shields that come with DRE) is that all mods that support DRE or add their own shields (B9, Tantares, Taurus, Bobcat, etc etc) would have to be updated as well, since they're balanced for 5.2.

I suggest marking 5.3.2 as an experimental release - obviously it needs some serious balancing before it's ready for general use.

[John FX]

The trouble here (updating shields that come with DRE) is that all mods that support DRE or add their own shields (B9, Tantares, Taurus, Bobcat, etc etc) would have to be updated as well, since they're balanced for 5.2.

I suggest marking 5.3.2 as an experimental release - obviously it needs some serious balancing before it's ready for general use.

I`ve changed my exponent from 0.5 back to 0.85 and it feels right. I tried to to an `engine heatshield` aerocapture for Eve and my whole craft burned up, including the fairings, leaving only my heatshielded lander (which was the intention) which used some of the heatshield for the rest of the entry. When set at 0.5 everything just burned up quick sharp.

Might take it down to 0.8, might leave it where it is. Time will tell. Now I just need to adjust the FX exponent to match (I set it to 0.6 and now get over the top effects as soon as I enter atmosphere)

i`d say for general release to have the exponent set at 0.85 and let people know they can set it harder if they like.

[smunisto]

My 5.2 SSTOs burn up on reentry no matter the descent approach I choose. I don't mind upping the difficulty, but as long as it is properly tuned to Stock/FAR(since almost everyone is now convinced, that FAR is the way to go) KSP as a baseline. From there on out, all other mods should be "optionally" supported and should provide their own DREC settings for appropriate heat simulation.

I don't mind playing with the settings on my own too, but providing something to be baseline sounds much better than just "tune until satisfied".

Gonna go back to 5.2 for now too.

[Mystique]

Is there a link to 5.2 download? Can't say that after 5.3.2 things became too hard, but losing all heat shielding just when doing upper atmosphere breaking passes is a bit weird.

By the way, is there a way to overheat/destroy inflatable heatshield (using reentry heat, not engines)?

[biohazard15]

Is there a link to 5.2 download? Can't say that after 5.3.2 things became too hard, but losing all heat shielding just when doing upper atmosphere breaking passes is a bit weird.

By the way, is there a way to overheat/destroy inflatable heatshield (using reentry heat, not engines)?

Search previous pages, I've posted a link to GitHub repo where all previous versions can be found.

[RedAV8R]

Search previous pages, I've posted a link to GitHub repo where all previous versions can be found.

Why post a link? GitHub repo link is on the OP. Oh that's right, nobody seems to be able to read for themselves.

[Starstrider42]

EDIT 2 : What are the units that these entries in the .cfg refer to?

crewGWarn = 450000 // when G damage reaches this level, warn the player

crewGLimit = 900000 // when G damage reaches this level, start killing crew

Surely that`s not nearly a million G?

No, those are accumulated points of G stress (set by crewGPower and crewGMin?). Anybody can survive 10 G's if it only lasts a second.

Edited October 6, 2014 by Starstrider42
Removed bug report, will make a separate post

[Mystique]

Why post a link? GitHub repo link is on the OP. Oh that's right, nobody seems to be able to read for themselves.

Already looked in Github link in 1st post, thou didn't found older versions. Little bit less rocket building and little bit more sleep requested =\

P.S. Now I seeee..

[Shania_L]

I am all for added challenge, but I am not entirely sure what this latest vesion is trying to achieve.

Admittedly this was a single test, but I was returning a multipart (~2tonne) craft behind a 1.25m heatshield on a 165x35km orbit. I burned through the entire ablative shielding before I got to 40km, but then nothign, the shield was hot, but nothing exploded, nothing crackled, nothing broke, I was sat there flames filling the screen and Jeb made it back home safely.

I thought things were supposed to explode when you ran out of ablative? isnt that the point of it, being a hard coating over the squishy contents. If the squishy contents can withstand maximum heating from 40km down then why should I bother with a heatshield if tis just added mass?

[Tidus Klein]

Ya I don't know what happend...my poor b9 shuttle can't even get past 50.000 with out going poof....hmmm looked at the cfg's for both dre's and b9's part heat things, seems b9 dosent specify a vector for the under side of the craft....odd

[Starwaster]

.

I thought things were supposed to explode when you ran out of ablative? isnt that the point of it, being a hard coating over the squishy contents. If the squishy contents can withstand maximum heating from 40km down then why should I bother with a heatshield if tis just added mass?

incorrect assumption. Running out of ablative doesn't mean the part should then explode. It still has a max temp that needs to be exceeded. The shield's max temp is usually higher than what it protects. And given the majority of complaints are things burning up too easily I don't think there's still a problem of things being to easy.

@tidus. Not odd at all. Some parts lack a directional vector because their shield protects omnidirectionally

[Shania_L]

Dont get me wrong, I am not saying its too easy far from it, I have had many low orbit vessels become expencive fireworks today ... fortunately all robotic even though my bank balance is tanking hard now.

If the shield runs out of ablative really fast, but can then still survive the majority of re-entry on its max temperature value alone, what was going wrong in my original post? Or is that the intended technique? Can the ablative sustain far higher temp than the max temperature value for shock loading (short duration) only? I was getting a very shallow decent profile so spent a long time at high altitude reulting in "fairly" low temperatures (around 1400-1600 iirc).

I didnt mention in the original post but Im using NEAR so I have a slippery atmosphere.

[Starwaster]

Guys (and guyettes if there are any)

Obviously this last release has had some problems, including some persistent balance problems..

There's two issues right now:

1. When flames appear.
   
2. How quickly parts overheat (too fast apparently)
   

The first one is the least important and has nothing to do with whether or not a part is overheating. It represents plasma and is the air itself being heated and will show up very early in a reentry. Yes it also shows up on ascent and too early apparently but it has nothing to do with parts overheating and that needs to be distinguished.

Point #2 is the more important issue and when giving feedback, the following should be provided:

Velocity

Altitude or air pressure / density

If using Real Solar System class shields or not

Stock sized Kerbin or Real Solar System (and which set of configs if not stock RSS)

If you've adjusted the default settings, what did you change and what values.

[NathanKell]

If you change density exponent (NOT afx density) to .85, you will get pretty much *exactly* the prior behavior. So if you want to "go back in time", do that, don't use an obsolete version.

For now I will release an update with just that, and Starwaster can figure out how things should be balanced later.

I also *do* want to point out that, until 5.3.x, much of the DRE thread was taken up by people talking about how reentry was too *easy*. So I figured, why not fix that problem, *and* use the real life density exponent. I did, of course, test a full reentry in a Mk1 pod (ballistic, not even lifting) and succeeded just fine, so it did not seem over-hard to me.

[Athlonic]

Ok,

I confirm I am quite pleased with 5.3.2

I just did a direct re-entry from the Mun (4 try needed though ^^ )

So I started at an orbit of 11400km aiming a Pe of 0km which gave me the desired re-entry angle of 20° when reaching 70km.

I had to use a drogue chute (from Realchute mod) otherwise I wouldn't loose enough speed and would burn up @ 20km

• Ship : MK1-2 pod with its standard DRE shield, 3 suicidal Kerbals onboard with orange suits.
  
• Velocity : around 3200m/s @ 70km
  
• G-Force peak : 8.9
  
• Temp peak : shield around 1250C° for some secs after ablative shield went out
  
• Real Solar System class shields : NO
  
• Stock sized Kerbin
  
• default DRE 5.3.2 settings
  

So my points and conclusion so far :

1/ these settings actually makes re-entry "deadly" if not properly planned

2/ they makes heat shield usefull

3/ they makes drogue chutes usefull

4/ direct Mun re-entry is still possible and honestly I think any direct re-entry from farther shouldn't be possible with standard heat shield

In order to survive a re-entry with 5.3.2, do not ever aim for a 30km Pe anymore !

Because this will lead in a <10° re-entry angle and you will definitely burn up before reaching 25km

The key is a 20° re-entry angle when reaching 70km and less than 3200m/s velocity and you should be fine.

(ie. a 250km orbit need a Pe of -100km to achieve a 20° re-entry angle)

I must admit that all this will make return from interplanetary ... interesting

Edited October 6, 2014 by Athlonic

[undercoveryankee]

Ok,

I confirm I am quite pleased with 5.3.2

I just did a direct re-entry from the Mun (4 try needed though ^^ )

So I started at an orbit of 11400km aiming a Pe of 0km which gave me the desired re-entry angle of 20° when reaching 70km.

I had to use a drogue chute (from Realchute mod) otherwise I wouldn't loose enough speed and would burn up @ 20km

• Ship : MK1-2 pod with its standard DRE shield, 3 suicidal Kerbals onboard with orange suits.
  
• Velocity : around 3200m/s @ 70km
  
• G-Force peak : 8.9
  
• Temp peak : shield around 1250C° for some secs after ablative shield went out
  
• Real Solar System class shields : NO
  
• Stock sized Kerbin
  
• default DRE 5.3.2 settings
  

So my points and conclusion so far :

1/ these settings actually makes re-entry "deadly" if not properly planned

2/ they makes heat shield usefull

3/ they makes drogue chutes usefull

4/ direct Mun re-entry is still possible and honestly I think any direct re-entry from farther shouldn't be possible with standard heat shield

In order to survive a re-entry with 5.3.2, do not ever aim for a 30km Pe anymore !

Because this will lead in a <10° re-entry angle and you will definitely burn up before reaching 25km

The key is a 20° re-entry angle when reaching 70km and less than 3200m/s velocity and you should be fine.

(ie. a 250km orbit need a Pe of -100km to achieve a 20° re-entry angle)

I must admit that all this will make return from interplanetary ... interesting

Sounds like the optimum angle for entering with the traditional amounts of ablative is steeper than it would be on a larger planet. Apollo was rated for between 5.3 and 7.7 degrees entry angle. Just another gotcha if you try to apply real physics to a tiny little world.

And can you elaborate a little on what speed and altitude you used the drogue chute at? I thought firing them while subject to serious heating would just destroy the chute.

[Athlonic]

I used defaults "Realchute" settings (1.25m stack combo chute, auto predeployement drogue @ 30km / main chute pre @ 900m full @ 700m)

I thought like you about opening drogue chute so high being weird, but actually the heat shield should protect it from burning up (I think)