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

[Lexif]

Yes, it is in my experience. The creator said he is using FAR. But with the lower drag from FAR you can still have quite a lot of speed below 10 km in Kerbin's atmosphere. G-force damage from the deploying parachutes is a real threat and the reentry window gets narrower because of that.

PS: I love the combination so far, the landings have been quite challenging (only landed probes on Duna and Laythe so far) and make for a good tradeoff for the higher launch efficiency of FAR once you've figured out designing rockets for it.

Edited July 25, 2013 by Lexif
added postscriptum

[Decoherent]

This may be sort of a silly question, but is there supposed to be some kind of on-screen display for this mod? I can see the temperature in the right-click menu, along with some coefficients I don't understand and the ablative level on the shields, but it's not clear to me if there is a display I can pop up without having to constantly right-click on parts to see how they're doing. Mind you, I've only landed 2 capsules with this mod, one of which went nicely, the other stopped via lithobraking

[sidfu]

the ablative level is with your fuel. after a fe4w times u get the angle down and wont have to worry about that. long as u dont come in to shallow or too steep u be fine. there is no onscreen desply for this game. any part thats starting to get damaged by geforce or temp u can hear like a burning noise. usualywhat i do is stop my reetnry line at about 5-10k area tht keeps it from being to steep or shallow. when entering line up with your apo if u coming in good it be no higher than 30 any hihger on the nav ball u can burn all your ablative off.

Edited July 26, 2013 by sidfu

[InfinityArch]

But to be honest, the parachutes snapping off doesn't seem like it should really be that serious of a threat, at least compared to the g-forces and heat from reentry; as I said, I'm not sure about where I'd go to look this sort of thing up, but IRL don't parachutes gradually go from partially deployed to fully deployed, rather than suddenly snapping open fully? That's the main reason for G-force damage on craft reentering the atmosphere.

[maackey]

There are ways to reduce the sudden impact of a parachute snapping open, but those are mainly for personal parachutes/people. Typically large metal cans don't care so much about the g-forces IRL.

I personally have designed my landing pods to be able to not use parachutes at all (they still carry one for backups though), which is quite difficult with both Re-entry heat and FAR, but doable, and incredibly fun . I got the idea from the SpaceX video with their reusable stuff. I clip in a fuel tank to the command pod, attach a couple radial engines, and the B9 air brakes (essential -- otherwise you'd need way too much fuel/rocket for it to really be considered a "pod") and start to burn when the ground is a couple hundred meters up and terminal velocity is under 200m/s.

Also, Decoherent: there is no visible display, but there are sounds that are played when parts start to overheat, and when parts are suffering structural strain damage due to rapid deceleration (or acceleration for your srb-only powered rockets ) When I hear large creaking groans, and the g-meter is over 6g's I decrease the flaps on my airbrakes a bit during re-entry to reduce my drag until I get low enough to open them fully again for a softer landing.

[rhoark]

B9's airbrakes are quite overpowered. Watching Kerbal Engineer as I deployed just two airbrakes on my space shuttle, it went from 200N to 1.4 kN drag.

[rosenkranz]

Yeah, I'm finding the parachutes a non-starter as well. Not only do they get ripped off but they tend to rip the part their attached to off as well.

I've had more luck with the air brakes from the B9 mod. If you map their toggle to the brakes then you can use them with some precision.

However I've been having a terrible time landing ssto rockets. By necessity they come in engines first and those don't shield much so parachutes, landing gear, lights and struts on the sides get burned off. The engines them selves do ok. Any thoughts on a stack mounted shield that would mount between the engine and the tank that could deploy shields out the sides to protect the rest of the rocket?

Or maybe a modified version of the airbrake that mounts radially but rather than brake it takes the heat?

Is there any way to at least ball park a viable landing trajectory? I'm a little lost as to when to do the deorbit burn to get a good decent angle. Any advice is appreciated.

[maackey]

edit: @rhoark: Just curious are those values stock or FAR? In stock I wouldn't need the airbrakes (although I've never actually tried re-entry with stock aerodynamics yet...), as the pod would have a terminal velocity of ~100m/s on final approach, but in FAR its nearly 400m/s without airbrakes -- that is if the pod could survive re-entry conditions in the lower atmosphere, which it cannot.

I agree they are quite good, but I haven't compared them with other mods' airbrakes to really deem them "overpowered". What are they more powerful than? Parachutes? They provide an entirely different role... apples and oranges. I dislike when people use the term "overpowered" for "good" or "effective". Its a relatively minor peeve, but I see it a lot on these forums.

Edited July 26, 2013 by maackey

[birrhan]

I thought this mod was FAR compatible. That said, I don't know how this kind of stuff works in real life, but it seems a bit counteractive that parachutes would suddenly go from partially deployed to fully deployed, which basically guarantees they'll snap off in this mod when using FAR.

I used parachutes three times last night in 0.21.1, FAR + DRE, on a capsule that gets blown free of a rocket during liftoff. Rocket disintegrates around 15000 m, and our terminal velocity falling back down from that is around 330 m/s. That's with chutes unfurled but not filled; they decelerate the pod to 250 m/s then unfurl and go straight to 8 m/s at around 500 m. Parts get knocked free, but the chutes worked. Using two radial chutes on an MK1-2 pod. You could try drogue chutes (orange) in addition to radial chutes, ought to improve your odds.

Pics of your reentry vehicle?

[Decoherent]

Also, Decoherent: there is no visible display, but there are sounds that are played when parts start to overheat, and when parts are suffering structural strain damage due to rapid deceleration (or acceleration for your srb-only powered rockets ) When I hear large creaking groans, and the g-meter is over 6g's I decrease the flaps on my airbrakes a bit during re-entry to reduce my drag until I get low enough to open them fully again for a softer landing.

Ah, thanks, I hadn't realized that there were diagnostic sounds, as I was playing with the sound off!

[rhoark]

That's with FAR, and by overpowered I mean unrealistic. Deploying the brakes would have increased the surface area exposed to the airstream by maybe 5%, not 700%.

[Decoherent]

One more question! I just wanted to see if I'm still not quite grasping re-entry physics, or it it's not actually possible to land the 3-Kerbal pod with just a single XL chute. I was trying to land my rescue pod last night, and must have reloaded a dozen times or more, trying a huge variety of re-entry angles, and ended up lithobraking every single one because my speed never dropped low enough to deploy the XL chute without it snapping off. Eventually I got frustrated and sent up a rescue pod to rescue the rescue pod, equipped with a drogue and a couple radial chutes, and that worked fine. Not knowing much about real capsule re-entry profiles, do they all use a drogue or something?

[jrandom]

I've safely landed the Mk1-2 pod using one drag chute and two radially-mounted regular chutes. I have to hit very shallow -- coming in from an apoapsis of 80km I lower my trajectory to intersect Kerbin a little over a quarter of Kerbin's circumference away from where I start my burn, and that seems to work pretty well. The chutes don't snap off (I deploy them once I've passed the "shows non-flaming shockwaves" stage) and the pod lands at around 7.7m/s. (This is with both FAR and DE installed.)

[NathanKell]

I've landed with three radials (=1.5x a single XL) and nothing ripped off.

[thescientist]

Errrr.... Anyone known if there will be a .21 upgrade?

[ialdabaoth]

Errrr.... Anyone known if there will be a .21 upgrade?

[ajwojo1210]

(off topic) I lol'd so hard at that. I didn't see the cat at first as well. My confusion was priceless.

(on topic) I guess until it is updated to .21.1 I shall wait to launch interplanetary probes and missions galore.

[sidfu]

if u snaping chutes off then take and strut them. also dont deploy your chute as soon as the reentry heat dies look at speed. faster u going the more g's deploying chute will cause. i never have my chute snape off now(mostly it blows due to g's due to hitting space or bad staging). for entering try to sop your reentry line at about 5-10k feet before it enters the planet is what i do.

[Synthesis]

I've asked this question so many times I'm apologizing in advance, but I've never actually gotten a working answer: is there a way for me to reduce (significantly) the heat multiplier? I love the idea of this mod, but I really need to ease into it, and having my undeployed parachutes explode while my command pod survives really doesn't seem like it's working. Particularly I'd like to edit something in the configuration files (the multiplier itself isn't enough).

[NathanKell]

You can change the maxtemps in the CFG.

[Tobyz28]

Hey any eta on when "soon" might be? :D Really need the challenge this mod brings back in .21... getting bored!!

[jrandom]

You can still run the .20 Deadly Reentry in .21. Seems to work okay for me.

[crimsonknight3]

You can still run the .20 Deadly Reentry in .21. Seems to work okay for me.

I've just came back to Kerbal after a short absense. Anyways, i've just tried running KSP with a clean install with *just* Deadly Re-entry installed and it keeps getting stuck at loading Squad/Spaces/PodCockpit/model & if i remove Deadly Re-entry it loads fine. Anyone have a work-around or jrandom can you tell us all exactly how you have it working okay for yourself?

Thanks, and a big thank you to the mod author for keeping this awesome mod going

[Synthesis]

You can change the maxtemps in the CFG.

Thank you for the answer. Is there any chance you can elaborate, or is it just that easy?

[sidfu]

I've just came back to Kerbal after a short absense. Anyways, i've just tried running KSP with a clean install with *just* Deadly Re-entry installed and it keeps getting stuck at loading Squad/Spaces/PodCockpit/model & if i remove Deadly Re-entry it loads fine. Anyone have a work-around or jrandom can you tell us all exactly how you have it working okay for yourself?

Thanks, and a big thank you to the mod author for keeping this awesome mod going

its not the mod doing that try removing teh part then after it compelely loads exit and put part in. ive had wher game gets stuck on a part when the modmanager.dll stops working while adding stuff.

and another thing. since .21 is out about time for somewhat a overhaul isnt it. well i dont mean a complete overhaul just fix some small issues then look to make the mod more smooth in use.