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

[somnambulist]

Starwaster -- did the bump to fuel tanks' max temp make it into the 7.03 release? I spent a few hours last night trying to diagnose fuel tanks overheating during launch. I plan to poke at it some more after work but want to ensure the max temp is getting set correctly by DRE.

[Carsaxy]

Do you realize the version file has nothing really to do with what dll you get?

Yes bit I thought that this file was updated with the test of the mod.

I still have some esplosione on the LP, maybe it's an interaction with "procedural fairings"

[MrLao]

...on the other hand, an unmanned pod (nosecone from ModRocketSys), a service bay with 2 Science Labs, 2 goo containers and 1.25 m DRE heatshield didn't survive a sub-orbital reentry. The pod heated up and went up in smoke but the heatshield actually dropped in temp from around 300 and downwards and no ablation whatsoever. Just reinstalled FAR+DRE+integrator manually, gonna see if it works tomorrow.

[Starwaster]

Starwaster -- did the bump to fuel tanks' max temp make it into the 7.03 release? I spent a few hours last night trying to diagnose fuel tanks overheating during launch. I plan to poke at it some more after work but want to ensure the max temp is getting set correctly by DRE.

It was supposed to have but I'm looking through it now and quite a few are still too low.

Yes bit I thought that this file was updated with the test of the mod.

I still have some esplosione on the LP, maybe it's an interaction with "procedural fairings"

The version file is supposed to be incremented each update, yes but in every way that matters it is 7.0.3

...on the other hand, an unmanned pod (nosecone from ModRocketSys), a service bay with 2 Science Labs, 2 goo containers and 1.25 m DRE heatshield didn't survive a sub-orbital reentry. The pod heated up and went up in smoke but the heatshield actually dropped in temp from around 300 and downwards and no ablation whatsoever. Just reinstalled FAR+DRE+integrator manually, gonna see if it works tomorrow.

Not familiar with ModRocketSys; it will likely need a set of config patches done for it.

[cipherpunks]

I'm sorry that I haven't read all 416 pages, but will ask anyway:

Someone uses DR with KW Rocketry?

My "fresh" 1.0.2 install freezes on MM phase when I try to load both latest KW Rocketry and latest DR. Nothing interesting in log (will post it if someone is interested). What can be the problem?

Edit: nevermind, found it here: https://raw.githubusercontent.com/Starwaster/DeadlyReentry/master/DeadlyReentry/DeadlyReentry-KWRocketryFairings.cfg

Edited May 18, 2015 by cipherpunks

[somnambulist]

re fuel tanks

It was supposed to have but I'm looking through it now and quite a few are still too low.

I think something is definitely off. This is a test launch with an initial TWR of 1.3 Stock aero, gravity turn is an approximately 5 degree pitchover at 100m/s and then following the prograde vector. Skin temp climbs to about 1100 before the tank gives out. Is this level of heating correct? Or is the PEBCAK?

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(Haibeth Kerman knows what's up.)

[Starwaster]

re fuel tanks

I think something is definitely off. This is a test launch with an initial TWR of 1.3 Stock aero, gravity turn is an approximately 5 degree pitchover at 100m/s and then following the prograde vector. Skin temp climbs to about 1100 before the tank gives out. Is this level of heating correct? Or is the PEBCAK?

http://imgur.com/a/IpxqH

(Haibeth Kerman knows what's up.)

No, of course that level of heating isn't correct. Not for something travelling a mere 336 m/s, but remember we have to increase the amount of heat and speed up the heating rate a bit.

Though it does seem a bit high considering the amount of exposure area... are you sure you were really prograde the entire time? (really you want +svel in MJ terms but since you have the navball on surface mode they're pretty much the same thing)

[somnambulist]

Though it does seem a bit high considering the amount of exposure area... are you sure you were really prograde the entire time? (really you want +svel in MJ terms but since you have the navball on surface mode they're pretty much the same thing)

Pretty sure. After the initial pitchover it followed the prograde vector pretty much by itself.

[MrLao]

Not familiar with ModRocketSys; it will likely need a set of config patches done for it.

I think the part from ModRocketSys behaved correctly, but the DRE heatshield didn't heat up att all.

[spacewalruss]

re fuel tanks

I think something is definitely off. This is a test launch with an initial TWR of 1.3 Stock aero, gravity turn is an approximately 5 degree pitchover at 100m/s and then following the pro-grade vector. Skin temp climbs to about 1100 before the tank gives out. Is this level of heating correct? Or is the PEBCAK?

http://imgur.com/a/IpxqH

(Haibeth Kerman knows what's up.)

I've had similar issues with an RCS tank (stock 2.5 meter one I think) on top of KW's largest 2.5 meter LF?o tank overheating on the way up and exploding, effectively cutting my rocket in half. Burning prograde, very gentle grav turn (10 degrees or thereabouts), speeds are low (last time my speed was around 300m/s at 14,000 meters!)

No screenshot sorry but I can make one if needed...

EDIT: THis has been a reocccuring problem with just this part in my launches.

[acc]

I get strange dV/TWR calculations using MJ. both is much higher in the VAB than in flight. The only thing I installed/updated was the latest deadly reentry.

data:

- KSP 1.0.2 x86

- MJ dev #459

- DR 7.0.3

- log

- installed mods

also reportet at MJ thread

Edited May 19, 2015 by acc

[Starwaster]

I get strange dV/TWR calculations using MJ. both is much higher in the VAB than in flight. The only thing I installed/updated was the latest deadly reentry.

Your installation of Deadly Reentry is coincidental to your problem, not the cause.

The problem you're describing for MJ2 has been around for a long time.

[spacewalruss]

I've had similar issues with an RCS tank (stock 2.5 meter one I think) on top of KW's largest 2.5 meter LF?o tank overheating on the way up and exploding, effectively cutting my rocket in half. Burning prograde, very gentle grav turn (10 degrees or thereabouts), speeds are low (last time my speed was around 300m/s at 14,000 meters!)

No screenshot sorry but I can make one if needed...

EDIT: THis has been a reocccuring problem with just this part in my launches.

Just did this launch, skin temp was approaching 1000k, screen shows alt and speed.

[Ser]

Starwaster,

Can confirm people's complains about plane heating at low speeds: got 400+ K and rising at 3000-4000m at 250 m/s. I think env. heat dependency on speed should be revised because IRL things don't get hot at subsonic speeds, they tend to ice actually.

[acc]

Your installation of Deadly Reentry is coincidental to your problem, not the cause.

The problem you're describing for MJ2 has been around for a long time.

yeah, I know MJ has no 100% accuraccy, but the numbers was way off. I tracked it down to the procedural heatshields. I tried to use them (stupid me) as structural landing feets.

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(first two images with DR .65m shields, another two with .65m p. shields)

Edited May 19, 2015 by acc

[Merill]

At 3-4k-Kerbin, you have 600 HPa (if i remember well my data)

irl, you fly at 8k-Earth => 300Hpa

And in DeadlyReentry, to be deadly, there's some x40 multiplier, => do not stay too long in the atmosphere.

126°C is not so hot... try flying higher.

I'm correct?

[Ser]

At 3-4k-Kerbin, you have 600 HPa (if i remember well my data)

irl, you fly at 8k-Earth => 300Hpa

So what? 600HPa should burn me? I'm certain that the heating goes mostly from speeds enough to turn the surrounding air into ultra hot plasma. On subsonic speeds air pressure (its density, to be exact) doesn't make sense.

And in DeadlyReentry, to be deadly, there's some x40 multiplier, => do not stay too long in the atmosphere.

As I understand, that multiplier is the heat production of the air (to be exact, plasma) during reentry. But when I go 250 m/s that's not a reentry and I'm not surrounded with plasma.

126°C is not so hot... try flying higher.

Let's suppose AJE works so it's not easy to get to stratosphere just to cool down. And... wheres the realism?

I understand that DRE tries to simulate Earth's reentry in Kerbin's conditions but after the reentry it would be nice to have Kerbin's atmosphere back ASAP.

P.S. Cannot stop wondering why there's no birds on Kerbin. Now I got it - they all have been roasted in the air

Edited May 19, 2015 by Ser

[Merill]

I'm probably communicating badly

I didn't want to say it's "normal".

600vs 300 : More atmospheric density = more drag = more heat (at constant velocity). I think (i'm not an expert).

I know it's not the main problem, but it may contribute a bit.

Maybe you can post your detailed measure like in http://forum.kerbalspaceprogram.com/threads/54954-1-0-Deadly-Reentry-v7-0-3-update-May-14-2015-%28The-Melificent-Edition%29?p=1949549&viewfull=1#post1949549 ?

Edited May 19, 2015 by Merill

[Ser]

Merill

600vs 300 : More atmospheric density = more drag = more heat

On Earth we've got 1013.25 hPa at sea level. Are all planes getting hot at low altitude? So that's not quite right.

Maybe you can post your detailed measure

Ok, I'll do it once I get to that PC (several hours later).

But it's not hard to reproduce: build a simple airplane and fly around for 5 minutes at 200-300 m/s and mid altitude and you'll be able to cook some eggs on your wings.

Edited May 19, 2015 by Ser

[Merill]

I'm looking at the deadly conf:

@aerodynamicHeatProductionFactor = 3.65 (default 1)

"aerodynamicHeatProductionFactor is a multiplier to velocity used when figuring out shock temperature ('external temperature')" from http://forum.kerbalspaceprogram.com/threads/120282-Physics-cfg-what-do-the-numbers-mean

ps: i also can't before several hours later .

Edited May 19, 2015 by Merill

[Ser]

Merill

The key word is "shock". So the multiplier shouldn't be applied in a linear way because below some mach value it's not a shock anymore. The lowest value should be 0 I guess as flying at 100 m/s shouldn't make you hotter by 100 degrees.

[Starwaster]

That's a good point about the multiplier; it does apply across the board even at subsonic speeds. (so you're basically transonic at ~90 m/s)

ConvectionVelocityExponent does only apply only at Mach, but I'm leery of meddling with that one. Even if it was exposed for us to screw with, that's your velocity^3 term and I think it would scale pretty badly for reentry to other planets where you'll probably have a higher velocity than for Kerbin.

I'm going to try inserting a special mach multiplier which only kicks in at Mach speed.

[Starwaster]

I'm not pushing this to an official update yet, but here is a new DLL to test:

Removes a lot of the spamming to the log if PartThermalData is not found. (however, if that happens, then the affected part will not heat up nor will it process heat)

OH and it should reduce subsonic heating

Updated DeadlyReentry.cfg (buffed fuel tank maxTemp. Part maxTemp is low at 1000 (which is more than 200 degrees higher than aluminum melting point) but skinMaxTemp is beefed to 2000. Note that this covers stock fuel tanks. Other fuel tanks in the rest of the config files are not changed yet.

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

https://raw.githubusercontent.com/Starwaster/DeadlyReentry/master/DeadlyReentry/DeadlyReentry.cfg

Edited May 19, 2015 by Starwaster

[xXIndestructibleEVAXx]

Ok, I just did a new test after removing far. I got to an orbit of 108x102, then burned down to decrease my orbit to 21x108. I flew in facing radial, and when plasma started appearing, I decoupled the last stage (landing gear, full fuel tank, poodle, and decoupler) so that I was only left with a command pod with a parachute. Nothing but solar panels and batteries blew up during reentry. Is it my descent profile? The stage probably had a large thermal mass, and decoupling probably took a lot of heat with it. Could it have been that? And lastely, what can I do to make something blow up, just so I can confirm that it is working?

[Starwaster]

Ok, I just did a new test after removing far. I got to an orbit of 108x102, then burned down to decrease my orbit to 21x108. I flew in facing radial, and when plasma started appearing, I decoupled the last stage (landing gear, full fuel tank, poodle, and decoupler) so that I was only left with a command pod with a parachute. Nothing but solar panels and batteries blew up during reentry. Is it my descent profile? The stage probably had a large thermal mass, and decoupling probably took a lot of heat with it. Could it have been that? And lastely, what can I do to make something blow up, just so I can confirm that it is working?

Sounds like you're describing the Kerbal X, so I took that ship and duplicated your orbit and reentry parameters.

And I pretty much lost the entire craft.

TPK.

Rocks fall, everyone dies.

And that's with a bug that Nathan says is causing parts to radiate twice as much as they should. Maybe that bug he describes is a factor in your survival but it sure didn't help my guys