[0.20] Deadly Reentry 2.3 - reentry heat, plus thermal and g-force damage to parts

[ialdabaoth]

I did give details at some point...honestly don't recall what thread....I was told not to use other mods....not really help in my book so I was just gonna forget about it

don't worry about it anymore, I'm not, but I do thank you for trying to help again

Told not to use other mods? Now I'm sure there was a miscommunication somewhere. The whole point of Module Manager is to help other mods.

[WedgeJAntilles]

Because spaceplanes such as the space shuttle don't use ablative tiles. Spaceplanes in the next version *will* use heat tiles, they just won't be ablative (i.e., they won't get "used up" as you go through the atmosphere).

YES! Very happy about this--I have a number of SSTO designs that I want to be 100% reusable, e.g. to station on Laythe, so having the heat shield ablate on re-entry was a big problem for me.

Well, sortof. I've also noticed, like a lot of people, that deadly reentry isn't that deadly anymore. I would expect that de-orbiting an unshielded spent stage from 250km orbit would end in a fiery explosion, but I've dropped a dozen craft that way and not had a single component overheat (best I got was about 1200C).

Also, I think it would make sense to try and balance it against the stock heat values -- I have a lot of part packs and it's not really feasible for your mod to update the values for every part that's out there.

EDIT: For reference, I am using FAR

Edited June 4, 2013 by WedgeJAntilles

[taniwha]

One thing to remember: Kerbin ain't Earth. 250km orbit around Earth: 7762km/s. 250km orbit around Kerbin: < 2200km/s (I don't know the exact value). That's less than 1/3 the orbital velocity or 1/9 the energy to shed.

Also, even with deadly reentry 1.3 (using FAR), I've had plenty of debris hit the surface with all parts: debris has a very high surface area to mass ratio (especially large tanks with mainsails, though I did lose many a mainsail) and thus decelerates pretty rapidly. When your max temp is 1450C, you need to be going at over 1800m/s at peak heat transfer altitudes to even begin to worry. Try some Mun free return orbits (though even then, the Mk1 command pod survives, but does get hot).

[ialdabaoth]

One thing to remember: Kerbin ain't Earth. 250km orbit around Earth: 7762km/s. 250km orbit around Kerbin: < 2200km/s (I don't know the exact value). That's less than 1/3 the orbital velocity or 1/9 the energy to shed.

Also, even with deadly reentry 1.3 (using FAR), I've had plenty of debris hit the surface with all parts: debris has a very high surface area to mass ratio (especially large tanks with mainsails, though I did lose many a mainsail) and thus decelerates pretty rapidly. When your max temp is 1450C, you need to be going at over 1800m/s at peak heat transfer altitudes to even begin to worry. Try some Mun free return orbits (though even then, the Mk1 command pod survives, but does get hot).

This is the real problem, I think. Accurate physics means that Kerbin almost never presents a real problem, unless you're doing something crazy like dropping straight home from Jool. I'm already tweaking quite a bit to make it even slightly 'deadly'; the question is, how much do we want to make this "hard mode" for the sake of hard mode, vs. how much do we want to make it reasonably realistic?

My preference is always towards moar sim, of course.

[King Jareth]

- B9 pack support.

Does that include the B9/ModuleManager 'funkyness' ?

Liking the sound of the EVA checks, always good to have a reason to suit up.

[Guest]

OK, I'm getting really strange behavior using this mod. I've got an ablative heat shield on the BobCat's Orion, which is a copy of the standard 2.5m shield. The problem is, upon reentry, the shield starts to ablate at -5 or so degrees (barely into the atmosphere), gets used up by the time flames start to appear, yet the capsule isn't damaged in any way. Same goes for Space Shuttle (CSS), which has heat shield directly based of spaceplane fuselages. This one loses it's heat shield long before the atmo starts to get thick, yet it doesn't seem to have a heating problem once flames start to appear. Is it how it's supposed to act?

[ialdabaoth]

Does that include the B9/ModuleManager 'funkyness' ?

Liking the sound of the EVA checks, always good to have a reason to suit up.

Yes; careo's given me permission to redistribute his dll (which we have successfully patched).

[Eric S]

This is the real problem, I think. Accurate physics means that Kerbin almost never presents a real problem, unless you're doing something crazy like dropping straight home from Jool. I'm already tweaking quite a bit to make it even slightly 'deadly'; the question is, how much do we want to make this "hard mode" for the sake of hard mode, vs. how much do we want to make it reasonably realistic?

My preference is always towards moar sim, of course.

A very valid point. I've been mentioning the difference in reentry velocity ever since people started getting worried that reentry heat was coming. The devs plan on dealing with reentry heat without involving heat shields, so I suspect that they're aiming for "You can either be cautious and enter from a reasonable orbit, or you can aerocapture and pay attention to where your more heat-sensitive parts are." They could be just aiming for "don't be stupid."

Of course, the more important point of view is yours. Personally, other than needing a heat shield, I never really felt that 1.3 made the game much harder. As long as I wasn't doing anything stupid and was actually behind my heat shield, I wouldn't even see a heat bar. Then again, I never did try aerobraking inbound from Jool into a nice low orbit with DR. As long as I slowed down enough to stay inside the orbit of the Mun, I was willing to finish up on subsequent passes.

I guess I'd say somewhere in between but not so much earth-hard as something you have to think about, even if that thinking is just "I'll settle for a light aerocapture and use another pass (or passes) to brake enough to reenter rather than change the design of the craft."

[Wert]

Great Mod! Here are some questions I have about how to edit the configuration of it. What config edits do you use to make a heat shield that isn't ablative? Also, what exactly do each of the parameters in REENTRY_EFFECTS do, and how could you change them to work with stock heat resistance? Finally, do you change the REENTRY_EFFECTS in DeadlyReentry.cfg or custom.cfg?

I also agree that this mod should be balanced with stock heat values, to make it compatible with other mods.

[WedgeJAntilles]

the question is, how much do we want to make this "hard mode" for the sake of hard mode, vs. how much do we want to make it reasonably realistic?

My preference is always towards moar sim, of course.

I would like to think there's a happy medium somewhere. As it stands, DR has no effect on 99% of my mission profiles, which sort of kills the point of using it in the first place.

Another thing to think about that still veers on the side of realistic is the heat values. Is 1700 really low enough? I mean, 1700 is roughly the melting point of steel, but I have a hard time believing that a rocket tank would heat all the way to the point of steel melting without taking ANY damage beforehand. I know this contradicts my earlier request to balance it against stock values, it's just something to think about.

[rifter]

That brings up an idea: as something heats up more and more, it becomes more vulnerable to structural failure under lower G-forces. This is all based on the idea that steel can still deform well below its melting point.

[ialdabaoth]

That brings up an idea: as something heats up more and more, it becomes more vulnerable to structural failure under lower G-forces. This is all based on the idea that steel can still deform well below its melting point.

Yep, all that is already factored in and working. In general, things start taking damage at 85% of their maximum temperature, so around 1450 Celcius things start being a little problematic, and around 1600 things go south fast.

[aquilux]

Maybe, we could use the animation module in some way to vary connection strength and impact tolerance dependent of temperature similar to how the inflatable heat shield works?

[taniwha]

I just checked, and the most common titanium alloy is "good" up to about 400C (probably higher, but that seems to be the design cutoff). Not sure what Kerbals use, though.

[Tripod27]

Yep, all that is already factored in and working. In general, things start taking damage at 85% of their maximum temperature, so around 1450 Celcius things start being a little problematic, and around 1600 things go south fast.

Now what does "taking damage" mean? I've seen it in the game reports (in stock KSP) and all that but does damage really do anything? Currently the three different settings a part can be in seem to be "fine", "disconnected", and "destroyed". I see no damaged effect besides on rover wheels. And you get the damaged warning whenever you splash a part with some rocket exhaust, but if you keep the rocket pointed at it nothing happens besides it being pushed away. So unless "damaged" means that it blows up or gets disconnected more easily, I think I'm missing something?

[King Jareth]

ialdabaoth has a 5(?) tier damage system in DR, you can see it in the right click menu for parts in game.

(not sure if thats just for G force damage TBH).

Edit - No its 6, he talks about it back here.

[MaHuJa]

I think the stock game "part x damaged by y exhaust" will purely increase the temperature of x until it hits the max for that part.

[Yoloswaggins]

Been testing this out and have come across one strange thing. I built a rover/skycrane thingy using the kerbal attachment system and was testing it on Kerbin.

No problems with re-entry using a heat-shield but when it comes to deploying the rover from the skycrane, it winches down about a meter and then the skycrane explodes.

According to the post flight screen the crane components are exceeding their g-limit.

The crane itself is drifting down at about 7 m/s on parachutes when this happens. I tried with KAS in both docked and undocked mode to no avail. I've no idea what's causing the g-overload and am presuming it's just an issue between KAS and deadly reentry.

Anywho just thought I'd give you a heads up as it would be nice to have the skycrane working. I'm enjoying both mods and don't really want to give either up, but I also love skycranes and don't wanna shelf those either. Dilemmas, dilemmas

[Tripod27]

it feels like most of the g-force limits are too low. One of my jets just rips itself apart while turning (granted it is a 11g turn) but even my more modest jets have their engines explode at 8.5gs, and at that turning speed it would take it ages just to do a 180 degree turn

hell, I added a joystick so my controls would be fine enough to not turn at 11 gs and explode, and then it ripped itself apart at 6 gs after a slightly longer flight. all of the small fuel tanks and contol surfaces just rip off, and then the fuel tanks hit other parts of my jet and explode, and then half of my jet is debris and the rest is falling to the ground

Edited June 5, 2013 by Tripod27

[ialdabaoth]

it feels like most of the g-force limits are too low. One of my jets just rips itself apart while turning (granted it is a 11g turn) but even my more modest jets have their engines explode at 8.5gs, and at that turning speed it would take it ages just to do a 180 degree turn

hell, I added a joystick so my controls would be fine enough to not turn at 11 gs and explode, and then it ripped itself apart at 6 gs after a slightly longer flight. all of the small fuel tanks and contol surfaces just rip off, and then the fuel tanks hit other parts of my jet and explode, and then half of my jet is debris and the rest is falling to the ground

This is a problem in general.

I'm basing my computations of G-force tolerance on crashTolerance.

So, what would the entire KSP community (at least those who use my mod) prefer:

1. Plane wings that can withstand 15 to 20 G's of acceleration, and pods that can reenter at 40 G's

or

2. Pods that break up after 20 G's, and plane wings that break up at 10 to 15 G's?

[yongedevil]

I haven't gotten as far as testing this in reentry but I've notice a problem in the editor. The parts with ablative heat shields cause a drop in FPS in editor. I'm using a rocket with six NCS Adaptors and six Standard NC and the editor becomes very slow after a while.

It isn't immediately noticeable upon launching the game but after flying an returning to the VAB a few times it is a fairly pronounced slow down. I've tried the Mk1 and Mk2 cockpits as well and they have the same effect so I tried removing the heat shield module from the parts and that cleared the problem. I have not noticed an effect in flight

Other mods I'm using:

Mechjeb v2.0.8.0 (tested both on and not on the ship)

Engineer Redux v0.6.0.3 (tested both on and not on the ship)

Ferram Aerospace Research v0.9.4 (also tested without FAR installed)

Crew Manifest v0.5.4.0

Ioncross v1.1

[Killerblonde]

This is a problem in general.

I'm basing my computations of G-force tolerance on crashTolerance.

So, what would the entire KSP community (at least those who use my mod) prefer:

1. Plane wings that can withstand 15 to 20 G's of acceleration, and pods that can reenter at 40 G's

or

2. Pods that break up after 20 G's, and plane wings that break up at 10 to 15 G's?

As someone who flies planes and wants realistic reentry, I'd pick number 2. With a few adjustments, perhaps you could give wings a little "boost" in G-force tolerance, although to be honest with you, a 10g turn in a plane is starting to get ridiculous. - http://en.wikipedia.org/wiki/G-force#Short_Duration_Shock_and_Jerk

Forgive me for citing wikipedia, but it makes sense that most aircraft never exceed 10 G's, with fighter jets only taking 10+ G's briefly and under extreme conditions. If you're doing a turn that would require 10+ G's, then your aircraft should be flying apart. I'd say keep the pod G tolerance as is, and give wings a little boost in crashTolerance or add some subroutine to increase the G-force tolerance.

[Tripod27]

Well the issue is that the planes tear apart at a sustained 6-7 Gs, and it's not the wings themselves, the rocket fuel tanks explode and then everything attached to them just falls apart. Most of the plane parts (besides the engines, which also explode often) can sustain 3-5 times the Gs of an equivalent rocket part, but when you're building a SSTO which needs rocket fuel, that one weak link is all it takes to break your plane apart into three pieces with a rocket fuel tank shaped hole in the middle

[taniwha]

ialdabaoth: pods probably should survive 40G acceleration. They're just not that massive. Using acceleration alone is bogus because there's the problem of what's connected to the part. A length of 25lb fishing line will survive 1000g just fine. Put a 10lb weight on the end, and it probably won't handle 3.

Also, basing G tolerance on impact tolerance is tricky because the acceleration in an impact is ridiculously high.

IMO, your mod most definitely should not be ripping ships apart, at all. Leave that to mods like FAR. Better yet, Deadly Reentry should not be worrying about acceleration at all. Leave that to a Deadly Acceleration mod, and that mod should not be affecting parts because the engine already does (though maybe not sufficiently, I will admit). However, Deadly Acceleration should be crushing Kerbals. Probes probably should be able to take 40g. Kerbals should not.

I wish I could remember the details, but I remember being surprised at just how much continuous vibrational acceleration a non-operating hard-drive could take. Even an operating hard-drive could take a surprising amount (though much less than when not operating).

[Killerblonde]

ialdabaoth: pods probably should survive 40G acceleration. They're just not that massive. Using acceleration alone is bogus because there's the problem of what's connected to the part. A length of 25lb fishing line will survive 1000g just fine. Put a 10lb weight on the end, and it probably won't handle 3.

Also, basing G tolerance on impact tolerance is tricky because the acceleration in an impact is ridiculously high.

IMO, your mod most definitely should not be ripping ships apart, at all. Leave that to mods like FAR. Better yet, Deadly Reentry should not be worrying about acceleration at all. Leave that to a Deadly Acceleration mod, and that mod should not be affecting parts because the engine already does (though maybe not sufficiently, I will admit). However, Deadly Acceleration should be crushing Kerbals. Probes probably should be able to take 40g. Kerbals should not.

I wish I could remember the details, but I remember being surprised at just how much continuous vibrational acceleration a non-operating hard-drive could take. Even an operating hard-drive could take a surprising amount (though much less than when not operating).

While I understand your argument, the purpose of including acceleration to the "deadliness" is because reentry must consider heat and acceleration. Otherwise, you can survive nearly any reentry just by nose diving straight down. This mod is meant to provide realistic, challenging reentry, which makes the inclusion of deadly G forces a must, lest an inaccurate heat model be introduced.