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

[jstnj]

And, I *think* that stupid_chris is doing checks for both heating and stress damage on the canopy.

Regarding heating, here's what governs which way heat flows: From hotter temperature to cooler temperature. How MUCH heat depends on the densities of the respective. At higher altitudes, sure the air is thin but so is the canopy. And the larger it is the more heat it can collect. So it can heat up fairly quickly. My guess is that it will fail from melting (or decomposition; Kevlar doesn't melt. It just weakens at higher temperatures and then comes apart)

And his code isn't even dependent on Deadly Reentry anyway. So you can definitely give it a try right now.

Actually I'm going to try it right now myself and see what happens. My guess is that it's going to be pretty ugly.

Soo I'm trying to figure out the context here...why are drogues needed for reentry? I remember a previous early version of DRE for .90 w/FAR was causing mk1 pods to never slow down enough for a chute...are we thinking it will be the same for the 1.0.2 version?

...and PS: is the current beta in github worth a test?

Edited May 11, 2015 by jstnj

[futrtrubl]

Soo I'm trying to figure out the context here...why are drogues needed for reentry? I remember a previous early version of DRE for .90 w/FAR was causing mk1 pods to never slow down enough for a chute...are we thinking it will be the same for the 1.0.2 version?

...and PS: is the current beta in github worth a test?

To slow the craft enough that a full parachute won't rip itself apart when deployed.

[Starwaster]

Soo I'm trying to figure out the context here...why are drogues needed for reentry? I remember a previous early version of DRE for .90 w/FAR was causing mk1 pods to never slow down enough for a chute...are we thinking it will be the same for the 1.0.2 version?

...and PS: is the current beta in github worth a test?

No version of DRE ever caused any parts to not slow down (enough, or otherwise). It didn't touch drag.

Any beta there would be for KSP 0.90 and not KSP 1.0

I am aiming more for a release sometime tonight, unless I find some glaring bug that requires immediate attention. The only tasks are to tweak space plane shielding which is tricky because passive heat shields no longer use a dedicated heat shield module. Instead they require tweaking of the part's various thermal related parameters. Interestingly I've found that drastically REDUCING thermal mass of the skin causes significantly less heating. I've never been able to actually get that to work so there's clearly a sweet spot in there where thermal equilibrium can occur. (this is actually how the shuttle tiles worked. They really couldn't hold very much heat, so they reached their maximum temperature very quickly very high up which meant that they basically could hold no more and would reject the rest. In KSP that actually tends to cause things to blow up but I accidentally achieved that when testing the SDHI heat shield trying to find the best configuration for Sumghai)

So long story short, things are mostly fallen into place and I just need to finish things up enough for a basic release. (the settings screen is going away for awhile; the stock thermal debugging screen controls DRE's parameters so it's there for tweaking if anyone wants it)

BTW, I tried the drogue test at very high up at atm 0.001 and it survived.... YMMV depending on starting altitude and speed....

[undercoveryankee]

It's not done in real life because unfortunately your assumption that there is somewhere you can decelerate at high velocities without heating is incorrect. If you are decelerating then your kinetic energy is being reduced. That energy has to go somewhere and that somewhere is in heating the air around the chute which heats the chute itself. Remember that the shock temperature in Kelvin is roughly equal to the speed of the craft and parachutes have a large area for thermal transfer and very low thermal mass so they heat very quickly.

Then there is the fragility, take a look at the supersonic chute on the LDSD test.

The theory (higher drag early in the descent can lead to lower peak heating) worked in principle for SpaceShipOne with the feathering wings. Remember that Earth's orbital speed is about five times faster than Kerbin's. From a suborbital trajectory with similar speed to a Kerbin re-entry, there might be a window of conditions where it would be possible to use an early drogue. It's just that from Earth orbit, you wouldn't have slowed down enough to be in that window until it was too late.

- - - Updated - - -

No version of DRE ever caused any parts to not slow down (enough, or otherwise). It didn't touch drag.

Heat shields are the right shape to exploit some glitches that OldFAR had that could cause insanely low drag. (I've heard that some versions of FAR would fall for a heat shield clipped into a command pod bottom node to bottom node, and I personally found a collider issue that would cause a 6S service compartment to shield a Mk1-2 heat shield attached directly under it). That's probably what happened to most of the people who got wild rides. Found a FAR issue that they wouldn't have found without the thin flat parts that we gave them.

[Surefoot]

I think the idea is by using a high altitude drogue you shed some energy *before* reaching higher density layers that means a bit of slowdown but not enough to torch the drogue chute, since we're talking about low density upper atmosphere. Then when you hit lower layers you'll have lost quite a bit of energy already which means less heating up at that point.. I tend to do that with airbrakes, but if drogue chutes can survive, for example when they are made of reflective material, why not ? Sounds like interesting experiments to come with DRE

[ss8913]

Starwaster did you say *tonight*? Awesome. I was just coming here to check up on this mod since I finally have a working FAR for 1.0.2 (thanks ferram4!) and honestly DRE is my other "must have" mod besides FAR ... it's nice that Squad added re-entry heating in 1.0 but even at maximum, you've got to be *really trying* to burn up anything on re-entry with stock heating. I miss DRE so I'm glad the release is imminent Thanks again for your hard work on this mod. as I said, if I could only have 2 mods, it'd be FAR and DRE.

[Synthesis]

Great to hear you're close to a breakthrough Starwaster--though I've managed to play 1.0 without DR (just the functioning parts), and I'm eager to get a working DR mod up again, I don't mind waiting for you to get it right.

[Drew Kerman]

I didn't think drogue chutes were used in any way for slowing something down. I thought drogue chutes were mainly used for stabilization of the craft in preparation for a main chute deployment - in addition to helping deploy the main chute as well in some cases

[Starwaster]

Deadly Reentry updated for KSP 1.0

There are far too many changes to list. This is a near total rewrite from the ground up to take advantage of KSP 1.0 new thermal system. The major difference is that only fraction of a part's mass (thermal mass) is used when applying convection heating. (convection is the main means by which reentry heating occurs)

This concept was used to track 'skin' temperature separately. Skin can have different max temp properties, different thermal mass, etc. Skin temperature will eventually propagate into the interior (what was previously 'part.temperature' is now a part's interior.

Chute damage is currently not implemented. Both stock and Real Chutes have had canopy destruction built into them if you open them up when it's either too hot or you are going too fast.

Crew and part stress damage due to G forces is in. Go too steep and you could kill the crew even if the craft survived reentry heating.

To Do:

* Switch 'on fire' damage to skin temperature.

* Switch from an instant destruction to gradually applying damage over time. (this is how previous versions worked.

* Reimplement mod settings. (currently, if you want to change mod's settings, do so in the stock KSP debug menu: alt-F12->Physics->Thermal)

Deadly Reentry version 7.0 - The Melificent Edition

Edited May 12, 2015 by Starwaster

[Fly Angry]

Thanks Starwaster!

[futrtrubl]

The major difference is that only fraction of a part's mass (thermal mass) is used when applying convection heating. (convection is the main means by which reentry heating occurs)

This is awesome Starwaster! Now I may begin my campaign in earnest.

Some questions regarding the above. Is there convective cooling? IE bidirectional flow. Radiative heating (and cooling), is that still to the interior or is that only for the skin now too?

These would allow radiators and heatsinks to be built easily and realistically, even active ones if we make a plugin for active heat transport between interior and skin.

[funk]

Amazing! Now, I'm able to have some barbecue again. THX!

[Svm420]

Getting a ton of NREs upon luanhcing a sounding rocket. Here are logs let me know what else you need. Didn't see any other NRE from any other mod, but let me know if you want me to try and remove any mods. I know I have a lot.

[futrtrubl]

Getting a ton of NREs upon luanhcing a sounding rocket. Here are logs let me know what else you need. Didn't see any other NRE from any other mod, but let me know if you want me to try and remove any mods. I know I have a lot.

That will be JSI tools issue. It's alarmHeatIndicator doesn't look to be compatible with new DRE. I'll log a github issue.

Edited May 12, 2015 by futrtrubl

[Svm420]

That will be JSI tools issue. It's alarmHeatIndicator doesn't look to be compatible with new DRE. I'll send roverdude a github issue about it.

Wait isn't JSI RPM thats is roverdudes mod is it? I maybe confused by what you meant?

[InsanePlumber]

My little contribution, textures converted to DDS format.

Link to Google Drive - Only for next 48h.

>>> Remember to remove the old textures, they have the same names as those converted to a DDS format) <<<

@Starwaster

Please use them in the next update. (or not, your will)

[futrtrubl]

Wait isn't JSI RPM thats is roverdudes mod is it? I maybe confused by what you meant?

Yup, it's RPM, I was thinking USI tools. Fixed the post after you posted.

[Svm420]

Yup, it's RPM, I was thinking USI tools. Fixed the post after you posted.

Alright makes sense now. I am trying it without that mod to see if the issue is resolved.

- - - Updated - - -

Still getting the errors without RPM installed

[futrtrubl]

Alright makes sense now. I am trying it without that mod to see if the issue is resolved.

Actually, I think I am wrong. I saw an issue with that in there but it may be completely unrelated. There are quite a few exceptions before the DRE exceptions and with the way plugins can interact I think I will leave it to the experts to diagnose.

[BmB]

Have you fiddled with how the air temperature is calculated in the first place for v7? The default 1.0 model isn't very good.

[Starwaster]

This is awesome Starwaster! Now I may begin my campaign in earnest.

Some questions regarding the above. Is there convective cooling? IE bidirectional flow. Radiative heating (and cooling), is that still to the interior or is that only for the skin now too?

These would allow radiators and heatsinks to be built easily and realistically, even active ones if we make a plugin for active heat transport between interior and skin.

If external temperature is lower than the skin of the ship then heat will be transferred convectively away, yes.

Have you fiddled with how the air temperature is calculated in the first place for v7? The default 1.0 model isn't very good.

No. Without knowing what your complaint is about air temperature, all I can really respond to that with is that air temperature is not the primary contributor to the temperatures you will experience during reentry. The contribution of air temperature is useful mainly in knowing what the precise density of the air is at a given altitude so we know how much heat to transfer to your ship during reentry.

Getting a ton of NREs upon luanhcing a sounding rocket. Here are logs let me know what else you need. Didn't see any other NRE from any other mod, but let me know if you want me to try and remove any mods. I know I have a lot.

Wow, ok, quite a few of those are Deadly Reentry related and I've a pretty good idea where from. I'll have to reevaluate how I'm caching a certain item. What happens if you revert to VAB and then try again? And does it do it every time you launch a rocket? What if you restart the game?

My little contribution, textures converted to DDS format.

Link to Google Drive - Only for next 48h.

>>> Remember to remove the old textures, they have the same names as those converted to a DDS format) <<<

@Starwaster

Please use them in the next update. (or not, your will)

Thanks! I'll take a look at them and see if we use them.

[Snafu225]

Nice Nice Nice Nice!!!!

But DR says there are 13 problems with module manager when launching the game and I'm running a heavily modified game, so I don't know which one's the culprit... I hope this is the reason, why I haven't needed a single unit of ablator disappear on a quick reentry test.

https://www.dropbox.com/s/rjaumwwm2lw4nzv/output_log.txt?dl=0

[BmB]

My specific complaint would be that the temperature from my tests seems to be calculated as the maximum of the ambient and your airspeed in m/s. Meaning if the ambient is about 300K and you're going 310 m/s it will be 310K, and if you're going 298 m/s it will be 300K. Rather than taking into account any kind of friction effects, or shock compression. The ambient temperature itself seems to be reasonable, it drops off nicely with altitude and varies at sea level with latitude.

Also, is the pressure not exposed directly as a value? I can't be sure but isn't there a science part that gives this value? And also, by setting the aerodynamicheatproductionfactor to 0, you should be able to get the "raw" ambient temperature, and use that as basis for calculations instead.

Edited May 12, 2015 by BmB

[Snafu225]

Nice Nice Nice Nice!!!!

But DR says there are 13 problems with module manager when launching the game and I'm running a heavily modified game, so I don't know which one's the culprit... I hope this is the reason, why I haven't needed a single unit of ablator disappear on a quick reentry test.

https://www.dropbox.com/s/rjaumwwm2lw4nzv/output_log.txt?dl=0

Additional: Okay I forgot that DR comes with it's own heatshield but there's the next problem. I can attach the heatshield and the decouplers, but I can't attach anything to them :/

Edit: Module Manager says: 13 errors related to Gamedata/DeadlyReentry/DeadlyReentry.cfg

Edited May 12, 2015 by Snafu225

[Ser]

Deadly Reentry updated for KSP 1.0

Great! Couldn't wait for it.

As I remember, settings for crew kill by over-G were there in previous version but by default they were close to the infinity. Where are they now, I can't find them? Are they realistic now?

Have some suggestions:

1. Could you make burn effects and explosions on reentry proportional to a part's mass? Because every time I see a fire and explosion on reentry that is bigger than the vessel itself I am close to a heart attack shouting out: "Oh my, Kouston, we have lost a whole god damn bunch of a ... never mind, it was just a tiny piece of a solar panel that exploded like a barrel of kerosene." The most exciting it gets when happens in cascade

2. May be someday breaking and exploding parts would inflict damage on their neighbors, at least the parts they are attached to? Because now you can place an antennae on a crew pod and say: "I don't care if it burns on reentry". But it should at least kill the ablation to make it realistic so noone wanted parts to get ripped off the vessel just like IRL. If you remember Columbia accident, a piece of foam that hit the ablation was enough to turn the reentry into a total disaster.

Also big explosions could cause unwanted momentum changes.

All that should really make us decouple everything we don't need before reentry.

Edited May 12, 2015 by Ser