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

[J.Random]

As said before, the resulting temperature increase in Kelvin is roughly equal to the object's velocity in meters per second. That's temperature.

Everything else in your answer (thanks for bearing with me, btw:D) is a well-known basics, but can I haz a link for the quoted part? I can't find the "shockwave temperature" anywhere. There's static temperature (for the non-moving gas at given altitude), there's dynamic or kinetic temperature (derived from kinetic energy of the flow), in sum they give total temperature, which remains constant across the shockwave, and stagnation temperature, which equals to total temperature at trailing edges. Which one is "shockwave temperature"? Stagnation/total temperature is kinda close to flow speed in m/s, but only at hypersonic speeds. It's close enough at M5 for perfect gas, or M6 for imperfect, but at M3 or M7 the difference is up to 300K. And it works only for Earth because there's static temperature (depending on height, or rather, on pressure and gas density) and specific heats ratio (depending on atmosphere composition) in the formula. If that's the one, it may work for Kerbin, but not for Eve or Duna.

[Starwaster]

Everything else in your answer (thanks for bearing with me, btw:D) is a well-known basics, but can I haz a link for the quoted part? I can't find the "shockwave temperature" anywhere. There's static temperature (for the non-moving gas at given altitude), there's dynamic or kinetic temperature (derived from kinetic energy of the flow), in sum they give total temperature, which remains constant across the shockwave, and stagnation temperature, which equals to total temperature at trailing edges. Which one is "shockwave temperature"? Stagnation/total temperature is kinda close to flow speed in m/s, but only at hypersonic speeds. It's close enough at M5 for perfect gas, or M6 for imperfect, but at M3 or M7 the difference is up to 300K. And it works only for Earth because there's static temperature (depending on height, or rather, on pressure and gas density) and specific heats ratio (depending on atmosphere composition) in the formula. If that's the one, it may work for Kerbin, but not for Eve or Duna.

The wiki article has some good information on reentry heating which more or less agrees with other literature I've read on the subject. There is an absolute wealth of information on government servers, a lot of it declassified from the 50s and 60s. I can't give you links to those because I don't have them anymore, but maybe some day I can get around to putting up all the PDF files I've downloaded. (for Nathan if nothing else; he expressed an interest in them for working on Real Heat)

Wiki link (directly to shock physics section)

http://en.wikipedia.org/wiki/Atmospheric_entry#Shock_layer_gas_physics

Keep in mind though that what DRE is using is extremely simplified as mentioned before. No stagnation, no real gas model. I did however assign different planets differing densities (in the form of differing gas constants) and that definitely does make some difference. Especially for Jool, though a real life reentry (Galileo) probably is a lot different.

Edit:

Comparison of Mars/Earth reentry

Index of NASA information on supersonic flight, reentries, etc. Not that useful IMO... kinda dumbed down.

Some FAA.gov stuff on reentry. Some useful information here but I dismissed it as not being relevant to DRE. (again, simplified)

Edited November 28, 2014 by Starwaster
Added moar linkz

[legolegs]

But if you can get past the upper atmosphere then you're pretty safe and can probably even land without chutes. (I read recently that the Venera probes freefell without their chutes the last 50 km) <-- EDIT: Oops that can't be right.... that must be a typo. Can anyone with actual knowledge on those probes confirm or refute that number?

I made an investigation for you Yes it is true.

Automatic interplanetary station Venera-8 was using traditional scheme with drouge and main chutes and had touchdown speed 8.3 m/s. Since it was able to withstand 335 g during reentry constructors decided it had too soft landing. Next pair of apparatus Venera-9 and 10 had only drouge chutes (to have more time for atmospheric analysis). After dropping spherical heat shield craft looked like that:

(source: http://www.laspace.ru/rus/venera910.php).

The flat conical thingy on top (similar to our FL-A5 Adapter) is called "aerodynamic blind" and acted as a sturdy chute. I found no data about impact force but both Venera'es were considered landed "soft" and successfully performed science program.

I've found an original 1976 paper (rus), see the second .djvu file here: http://sovams.narod.ru/Venera/9-10/ki-xiv-5.html

As we can see here (data collected during descent), the chute was cut at 50km, no typo there:

Line and scale marked H represents height, horizontal axis is time h:mm.

Paper also said the terminal velocity (for <~1500kg lander with ~2m diameter) before touchdown was ~7 m/s. Such a soup.

Further read in English: Don P. Mitchell: First Pictures of the Surface of Venus

Edited November 28, 2014 by legolegs
additional data

[Moesly_Armlis]

Having issue with spontaneous combustion of kerbals while on EVA. This is happening random, but it did happen while I was driving around today and Jeb was va-poo-rized. So i removed every mod that I was not going to need for the race challenge and left in DRE. Completed a few races, built different vehicles and then all of a sudden Bill starts cooking.

This is with the DRE 6.3.2 beta version, but it has happened with DRE 6.2.1.

Mods in use are Toolbar, ATM, DRE, KER, HullCam, RSCFX, NG, PT, StockBugFix

[Starwaster]

I made an investigation for you Yes it is true.

Automatic interplanetary station Venera-8 was using traditional scheme with drouge and main chutes and had touchdown speed 8.3 m/s. Since it was able to withstand 335 g during reentry constructors decided it had too soft landing. Next pair of apparatus Venera-9 and 10 had only drouge chutes (to have more time for atmospheric analysis). After dropping spherical heat shield craft looked like that:

http://www.laspace.ru/rus/images/venera95.jpg

(source: http://www.laspace.ru/rus/venera910.php).

The flat conical thingy on top (similar to our FL-A5 Adapter) is called "aerodynamic blind" and acted as a sturdy chute. I found no data about impact force but both Venera'es were considered landed "soft" and successfully performed science program.

I've found an original 1976 paper (rus), see the second .djvu file here: http://sovams.narod.ru/Venera/9-10/ki-xiv-5.html

As we can see here (data collected during descent), the chute was cut at 50km, no typo there:

https://img-fotki.yandex.ru/get/15483/3844448.0/0_c426a_88add60c_L.jpg

Line and scale marked H represents height, horizontal axis is time h:mm.

Paper also said the terminal velocity (for <~1500kg lander with ~2m diameter) before touchdown was ~7 m/s. Such a soup.

Further read in English: Don P. Mitchell: First Pictures of the Surface of Venus

Thanks for that information! Very interesting.

Having issue with spontaneous combustion of kerbals while on EVA. This is happening random, but it did happen while I was driving around today and Jeb was va-poo-rized. So i removed every mod that I was not going to need for the race challenge and left in DRE. Completed a few races, built different vehicles and then all of a sudden Bill starts cooking.

This is with the DRE 6.3.2 beta version, but it has happened with DRE 6.2.1.

Mods in use are Toolbar, ATM, DRE, KER, HullCam, RSCFX, NG, PT, StockBugFix

I've seen this reported once before (or something similar) but I need reliable repro instructions because so far I haven't been able to make it happen.

I notice you mention driving, does it ever happen when NOT driving some kind of rover? Just sitting on the surface?

[Moesly_Armlis]

The save file is at the start of the race and have now replayed several times without burning. There is a save from the runway and will try out from there as that is the save where it occured with Bill.

On a previous occurance I was walking. And on that save file the problem was repeatable. I remember walking, going around what I thought was a problem area, and reloading serveral times. It seemed to occur in the same place but maybe it was happening at a specific time. Even stopped walking but burned up anyway.

Edit: This bug hunt is almost over. The savefile from the runway gives repeatable burnings. In fact from my experiments it looks as if the command seat is a hot seat. The racecar has a command module attached, it is decoupled and Bill exits. Bill's tempurature is zero at this time. Climb aboard the command seat and his temperature starts increasing. Once exit the seat the temperature stops increasing. However once reaching 500 and the FX start, exiting from command seat does nothing and temperature continues to rise until crispy.

Edited November 29, 2014 by MoeslyArmlis
Be weary quiet. Its bug hunting season.

[Gryphon]

Well, Bill is a hot pilot.

[RuBisCO]

Question: does changing the FX range change when the special effects come on? I try changing it but it seems to do nothing (I hit save).

[Fizwalker]

I think I've found an issue as well, but this could be operator error too. I'm starting to mess around with RSS/RO mods and I am attempting to launch my first rocket (Using FASA, Procedural Fairings, RT, RF, and stock parts) based loosely off of the Titan II (without the solid rockets) and after I reach an altitude of about 6.5km the rocket disassembles itself explosively. First time was without MJ installed and it occurred at about 150 m/s, and just after I pushed very slightly (~5 degrees) into the gravity turn. My second attempt used MJ to control the rocket and it was around the same altitude and I think the same speed. I had open the FAR panel so I could see if there were any warnings and either there wasn't any posted, or the problem occurred so quickly, that none were able to be displayed.

After writing this, it occurs to me that I might have been approaching Mach 1 and the transition might have over stressed the ship. I would be interested in hearing your thoughts on the problem and maybe some pointers to get me looking in the right direction. Thank you for your help in advance!

[Starwaster]

Rubisco, make sure you have this dll (the last beta download has a bug)

https://www.dropbox.com/s/moge45bumutdcwj/DeadlyReentry.dll?dl=1

Fizwalker, are parts burning up? Or just coming apart? If the latter then that's FAR not DRE. FAR will punish you for abrupt supersonic maneuvers.

[Artophwar]

I will add that I had a rover driver burn up on kerbin. He was in an external command seat. It was not on the runway but out near the base of the mountains by the KSC. Once the pilot caught fire there was nothing I could do to stop him from burning up. The rover was travelling at 20m/s.

[Frederf]

I set the settings to "hard" but I only lost 10 units of shield out of 1000 from a direct reentry from the Mun.

What are some actual good settings such that a full shield direct reentry from Mun is about 50/50 reentry depending on profile (too high = loss of shield and overheat, too low = over-G)?

[Starwaster]

I set the settings to "hard" but I only lost 10 units of shield out of 1000 from a direct reentry from the Mun.

What are some actual good settings such that a full shield direct reentry from Mun is about 50/50 reentry depending on profile (too high = loss of shield and overheat, too low = over-G)?

Was it stock Kerbol system, or RSS? (and if RSS, was it stock RSS, 6.4x Kerbol or 10x Kerbol?)

For hard, you might try turning off the alternate density setting. But that can REALLY make your reentry harsh on your shield.

[Lechuza]

Version 6.3.1 was messing KAS container functionality for me. Thought I should let you guys know.

I reverted back to 6.2.1 and everything seems to be working fine. Haven't tried with 6.3.2.

[Contagano]

I was getting the container error too. I'll report back the results of 6.3.2

[Starwaster]

Version 6.3.1 was messing KAS container functionality for me. Thought I should let you guys know.

I reverted back to 6.2.1 and everything seems to be working fine. Haven't tried with 6.3.2.

That bug was fixed with 6.3.2

Also, anyone with burning Kerbals please make sure you are updated to beta 6.3.2

Edited December 1, 2014 by Starwaster

[sidfu]

so far no problems with newest. only thing on the smaller heat sheilds might want to move the bottom node down a bit as its so close to the top node its a pain to get the smaller sheilds on. i wnd up putting them on larger stuff expanding them then putting on the small ship as when they expanded made it easier to put it on.

[Moesly_Armlis]

Great job fixing the burning Kerbals!

[MalfunctionM1Ke]

Is this supposed to happen? If yes, DR is making all my SSTO's not working anymore.

Stock Aero.

Edited December 1, 2014 by MalfunctionM1Ke

[taniwha]

MalfunctionM1Ke: your flying is at fault: you are going too fast for the altitude. You need to be somewhere between 25km and 30km for that speed to be vaguely safe (I think things will still get warm).

[MalfunctionM1Ke]

Oh I think I got it... It might be KSP Interstellar that causes the overheating. nevermind

Edited December 2, 2014 by MalfunctionM1Ke

[Starwaster]

Is this supposed to happen? If yes, DR is making all my SSTO's not working anymore.

Stock Aero.

http://i.imgur.com/yQ4hEQ6.jpg

Try the latest beta and see how it is then.

(but Taniwha is probably right and that probably is too fast. You're travelling faster than an SR71 but at 4-5km under the altitude that it would be travelling that fast at. The beta will give you a little better control and it's - I hope - a little better calibrated in the latest version. But that process is probably not finished yet)

Edited December 2, 2014 by Starwaster

[Screpheep]

So, I installed deadly reentry, but i decided I dont want to use this mod. How do I uninstall it? I deleted the folder from gamedata, but when I turn the game on again, the mod still works, Only thing that changed is that mod icon on toolbar, it is now completely white, but still works. I do not want to reinstall the game, cos I have like 20 other mods and I do not want to go through the process of downloading them all again. What should I do?

[Starwaster]

So, I installed deadly reentry, but i decided I dont want to use this mod. How do I uninstall it? I deleted the folder from gamedata, but when I turn the game on again, the mod still works, Only thing that changed is that mod icon on toolbar, it is now completely white, but still works. I do not want to reinstall the game, cos I have like 20 other mods and I do not want to go through the process of downloading them all again. What should I do?

Sounds like you only uninstalled its Assets folder. That white square means that the toolbar cannot find its icon pictures.

And/or have an extra copy stashed somewhere in GameData

Or have a copy of the dll somewhere it doesn't belong, like the KSP*/Plugins folder. (don't ever do that. Especially not ever)

Bottom line is if you really deleted its folder from GameData and it was installed properly to start with then it no longer would exist when you deleted it.

[MartGonzo]

I'm having some weird issues with heatshields, and the stack decouplers with RSS

they're all the wrong size, I put the RO_DeadlyReEntry.cfg in Gamedata I have the latest version of Tweakscale (but the heatshields and stack decouplers don't scale)

here's an example

2.5m heatshield almost fits

Mk1 stack decoupler

Mk 1-2 stack decoupler