Aerocapture in 1.0.4?

[Casper139]

Need help here.

Before 1.0.3/1.0.4 patches, I used Jool to aerocapture with a mining craft I've been working on. The goal was to land on Tylo. My first attempts at aerocapture got me into Jool orbit and I easily transfered to Tylo. I came up short of fuel to land however, but that's beside the point. I built a new lander and was trying again today after the recent patches. My Periapsis entering Jool atmosphere was always between 185000 to 190000. Now, as soon as I hit the atltitude of about 198000m, My craft explodes. Ironically, I placed heat shields on the craft before the patch was released. I enter the atmosphere prograde leading with sheilds. How do we Aerocapture now? Does my design suck?

[maccollo]

It explodes doesn't say very much? Are your decouplers getting fried? Does it flip around?

Anyway, you don't need to do aerocapture at Jool. You can just swing by Tylo. It's fairly easy to set the right encounter during one of the course corrections half way from Kerbin to Jool.

[One-Way Films]

you might wanna bring the design back to kerbin or make as much use out of that craft as you can. You'll need some radiators to take some of the heat away from the fuel tanks. The design has all the fuel tanks bunched together and a heatshield is merging into one of those tanks. Convection will bring heat across to the already heated fuel tank (just behind the 3m heatshield) and cause your explosion. You could alter your course and get a gravity assist around Tylo into the Joolian system. From the Tylo assist, aerobrake around Laythe. It's atmosphere is much thinner and that craft has a much larger chance of surviving Laythe entry. From Laythe, go on with your normal plan. Depending on how the moons are aligned, you can save or lose fuel. good luck!

[Xannari Ferrows]

Are you sure all of you're craft is protected from the airstream? Heat can transfer between parts through convection, so that could also be it...

[Vaporo]

My recommendation for anyone who tries aerocapture around Jool: Just use a Tylo gravity assist. Aerobraking is sometimes the best way to go, but recently I've found that it's just much, much easier to use gravity assists. Though... that thing looks likes it should work. Maybe try for a higher periapsis? I can never remember the atmosphere height on Jool. I think reentry heating is supposed to be more severe in 1.0.3. I'm not sure.

[Casper139]

The Craft just explodes. Thermometers blink for a half second and boom. No flips or anything. The shield appears to merge in the picture, but they do clear. I will try a new approach rather than a Jool AC. Gravity assist will be a new thing for me. Thanks for the suggestions.

[NathanKell]

Heating is proportional to v^3.

Entry at 10km/sec is much, much, much deadlier than Munar reentry on Kerbin (3km/sec).

[Pixel of Life]

Check the heatshields - running your engines near max temp for extended periods of time actually eats up all the ablator unless you have some sort of insulator between the shield and all the other stuff.

[PB666]

Did anyone check the F3. This could just be a 1.0.4 Kraken. If so I got the name 'Don't tread on Jool, Kraken'.

If is a real DOT then F3 will show some temporal progression.

[franklinreinoza]

I have the same problem. My craft explote as soon as touch the atmosphere and it dosent care wich planetplanet ist, Jool, tylo, laythe etc. In all explode, after one mili second in the atmosphere.

The speed of my craft, it's around 8km/s

[Reactordrone]

It's possible to overheat the heatshields now if the heating is too rapid. No idea if this is a feature or a bug.

[selfish_meme]

It's possible to overheat the heatshields now if the heating is too rapid. No idea if this is a feature or a bug.

http://img.photobucket.com/albums/v499/swampmonster/Kerbal%20space%20program/heatshield%20destruction_zps5ucdbxhh.jpg

Feature

[Guest]

You have to use much shallower approach angles now. If your craft explodes, check the flight log. If it exploded from overheating you need to raise your periapsis for aero capture.

[Alewx]

You have to use much shallower approach angles now. If your craft explodes, check the flight log. If it exploded from overheating you need to raise your periapsis for aero capture.

But where can we find the correct angle for an reentry or aero capture maneuver?

Does MechJeb provide this angle; Engineer does not.

[Richy teh space man]

I'm finding these new heat effect mechanics to be a pain, most of the craft I had built for 1.02 now explode on re entry, even with shallower descent angles.

I'm finding it off putting all these changes to the atmosphere that keep happening, just wish Squad would pick one model and stick with it rather than changing it every other update..

[Superfluous J]

I'm finding these new heat effect mechanics to be a pain, most of the craft I had built for 1.02 now explode on re entry, even with shallower descent angles.

I'm finding it off putting all these changes to the atmosphere that keep happening, just wish Squad would pick one model and stick with it rather than changing it every other update..

I haven't tried it yet (stupid work getting in the way of my play time) but I hope that if re-entry is as bad as everybody is making it out to be, that the model they settle on is this current one

[miceliux]

I was experiencing this same issue in 1.0.2 while aerobreaking on Jool at 10km/s.

I tried different apoapsis, and I was able to do it at a height of about 195 km. Even 1 km of difference could make my ship explode.

[magnemoe]

I was experiencing this same issue in 1.0.2 while aerobreaking on Jool at 10km/s.

I tried different apoapsis, and I was able to do it at a height of about 195 km. Even 1 km of difference could make my ship explode.

Weirdly I did the same with this ship

It had this tug

on the back, it went almost well, did 195 km came in with nose and heatshields first. first time the atmospheric messurment instrumets blew up so I moved them inside containers with KIS and tried again,

much better except that the ship started to tumble shortly after Pe, and ended up going engines first, a couple of ladders blew up else ship was unhurt.

[Guest]

So, it now seems that roverdude's radiators are standard equipment if you plan on aerobraking or reentry, even if it's just from the Mun. Because, forgive me, but I just do not find it fun to go round and round and round and round just so I can land my Mun lander back on Kerbin.I realize that there are other ways of dealing with the reentry heat, like heat shields or even changing the difficulty settings. But, the heat shields are heavier than radiators, and I like at least trying to play the game as intended for a while before making major changes to .cfgs or difficulty.

So is this what was intended? Pushing us towards using radiators for reentry? And for those of you that carry over saves from version to version, this must suck big time, especially since one would think that a 1.0 release would mean no more save breaking. I think it's safe to assume now that the 1.0 label meant absolutely nothing.

[NathanKell]

If you don't have a heatshield, >3km/sec is not terribly survivable.

[Nich]

I hate to say it but all of my old craft will simply require 3-4 passes at 40k. The big problem is that ships that used to barely survive with 2 chutes now need 3. If your like me with trouist in said craft be prepaired for lots of orbit lowing before entry and aiming for a water landing. At least the delta-v savings from easier launches offsets the fact just about every craft will need a heat shield.

[Magniff]

First of all, what this new feature is intended to do:

(Unfortunately I don't know how to properly quote an article, therefore I used this little dirty trick )

* Added a factor to simulate the switch from laminar to turbulent flow (in layman's terms, if you're going too fast too low, you get a massive boost to heating). That corrects so steep reentries are in fact deadlier than shallow ones.

Since reentry on Kerbin is currently rather harmless, I fundamentally agree with the new "to fast, to low" feature (introduced by patch 1.0.3).

There should definitely be at least some basic threat to burn-up during reentry.

In addition, you'll probably only encountered this new feature if you intentionally try to destroy your vessel.

But, I dislike the way this new feature is implemented:

Any part that exceeds a particular velocity on a given atmospheric density, will be instantly destroyed by overwhelming amounts of heat.

Futhermore there seems to be no consistentl heat progression towards the burn-up.

Instead the maximum skin-temperatures will tend to drop for some seconds, until the final burn-up occurs.

There's also no recognisable burn-up order of the involved parts.

It's not like: Your heatshield goes first, afterwards (almost simultaneously) your batterys overheat and finally (with a small delay) your fuel-tanks explode.

Instead the entire burn-up feels much more like crashing into a wall!

To illustrate this behaviour, I've prepared some pictures from my previous reentry testing in 1.0.4.

The test-vehicle's apoapsis is slightly above Minimus orbit, it's periapsis is close to the center of Kerbin.

Inital reentry velocity at 3.3 km/s.

Max. recorded skin-temperature is at roughly 2900 °K (all my other screenshots showed a lower skin-temp.).

You can also see the vessel's propulsion-stage, falling in front of it at 600 m distance.

Skin-temp. has allready droped by almost 200 °K, less then one second away from final burn-up.

In front, you see the propulsion-stage hitting the "to fast, to low" wall.

More than 2 km/s below 19 km altitude? - KSP says: Nay!

In this screenshot, you can also see the temperature gauges of some parts inside the explosion.

But you probably won't be able to recognise them during normal gameplay

Maybe the feature is intended to simulate g-forces instead of heating, you might say.

In this case, I'd at least expect to see a recognisable order of structural failures.

According to the individual part's impact tollerance.

What do you think about the new "to fast, to low" feature?

Should it be rebalanced or is it fine as it is?

(Please excuse any scribal errors or flawed grammar in my posts!)

Edited June 24, 2015 by Magniff
clarification

[NovaSilisko]

This is basically what happens to meteors in real life, see Chelyabinsk

[regex]

You're going 2km/s and hitting the thicker atmosphere of Kerbin, I don't see a problem here.

[sal_vager]

Moved to gameplay questions, also, you have to take aerodynamic heating into account now, this is a long requested feature.