Jump to content

One way stock 1.0 heat shielding is a bit unfair versus old DRE mod's heat sheilding.


Dunbaratu

Recommended Posts

Well, perhaps we're supposed to properly deorbit and reduce speed first before entering kerbin, instead of only worrying about getting captured by the atmosphere straight from the mun..

The problem occurs even with the mildest possible de-orbit - going from a 72km circular kerbin orbit, to dipping the periapsis down to 38km. I'm guessing they changed the mass of things so that the science Jr is no longer moving the center of mass far enough down, and so the described arrangement ends up being topheavy when it wasn't before.

Link to comment
Share on other sites

well after a bit of career ii found the answer- just upgrade your Astronaut complex ASAP and get EVAs anything beyond Goo and little experiments should be jettisoned before hitting atmo and collecting science with EVAs

Link to comment
Share on other sites

Dropped in from a 300km orbit, and heating got a bit nasty. The Mk1 + heatshield has a tendency to fly "corner first" which isn't an issue dropping in from a 100km parking orbit, but from 300, the heat pushes through to reach the parachute. It didn't actually burn up, but it was a bit close. Still not seeing any actual flipping behavior though.

Link to comment
Share on other sites

I kept SAS on, and tried turning it off a few times down towards ~40km, and it was not stable, so I gave up and controlled it past that for fear of killing someone. In FAR, the capsule wobbles around stability until dense air, then is fine, it never tumbles the wrong way one there are aerodynamic forces on it unless you provide input to do so. I assumed it would hit (I was already facing retrograde) the atmosphere, and do the same, not flip.

I can understand it getting more stable with dense air, but I can't see it starting off completely unstable, then flipping.

Link to comment
Share on other sites

Dropped in from a 300km orbit, and heating got a bit nasty. The Mk1 + heatshield has a tendency to fly "corner first" which isn't an issue dropping in from a 100km parking orbit, but from 300, the heat pushes through to reach the parachute. It didn't actually burn up, but it was a bit close. Still not seeing any actual flipping behavior though.

I keep saying to myself that I'm doing this wrong, that there's no way that stuff like this has made it past QA. But I dunno. I might still be trying to do stuff the old-fashioned DRE + FAR way.

Link to comment
Share on other sites

I also got the flipping problem when having like a Science Jr under the pod. However this did not happen with a simple capsule.

A quick workaround is to open your chute in space, or in the upper atmosphere. It will keep you straight.

By the way, chutes are CRAAAAAZYYYY OP ! when doing this trick you slow down from suborbital speeds to 340m/s in like 2 secs (crazy g force) when the chute isnt even fully deployed ! I found myself falling at 100m/s while i still was at 18000m !!!

The parachute doesn't even rip the ship off or tear down !

BTW ! (and this is awesome) you can pitch up or down to tilt the capsule to create a lifting body effect (just like Apollo did) and actually either glide or dive into the atmosphere ! i found (or is it just an impression ?) that you really can change your trajectory that way.

(although i love 1.0 right now, i strongly feel that this should be called .95 beta... )

Edited by Hcube
Link to comment
Share on other sites

I think if you fly a capsule, heat shield and parachute (undeployed) it will remain stable, but if you put anything between the capsule and the shield, for example an equipment bay or a materials bay, the CoM is far enough back that it is unstable. I went to orbit with an equipment bay containing a couple of goo canisters. I de-orbited by bringing the Pe down to about 30 km, and I found that with SAS on, provided I kept the pointer on the nav ball within the ring of the retrograde marker I was OK, but if it wanders outside the retrograde marker, then you're toast. Once you have a pilot who has been to orbit, just put the SAS on retrograde and you should come down safely. Only thing to be careful about is running out of power because the twitchy SAS in this situation eats up your battery. I think it's better to go for a much lower energy re-entry profile, though (but I've not had time to properly experiment).

Link to comment
Share on other sites

I also got the flipping problem when having like a Science Jr under the pod. However this did not happen with a simple capsule.

A quick workaround is to open your chute in space, or in the upper atmosphere. It will keep you straight.

By the way, chutes are CRAAAAAZYYYY OP ! when doing this trick you slow down from suborbital speeds to 340m/s in like 2 secs (crazy g force) when the chute isnt even fully deployed ! I found myself falling at 100m/s while i still was at 18000m !!!

The parachute doesn't even rip the ship off or tear down !

(although i love 1.0 right now, i strongly feel that this should be called .95 beta... )

This. Seriously. Opening a chute...in space?!?! And it does not rip and it does not burn?

Link to comment
Share on other sites

Re-entry soup-o-sphere style doesnt work anymore, 2 types of re-entry with Pods work fine, first the old shallow angle, but this means you have to slow down alot before capturing yourself by the drag in the upper atmosphere, this will become later even more so important when you start with spaceplanes, slowing down in the upper most regions of the atmosphere is the way to not get desintrigrated by heat and drag.

If you grab the upper atmosphere right, the MK1 pod can take the heat easy and slows down nicely..

But you have to be gently on electricity usage, you will need it to keep the pod on the correct angle, or you have to be really good with manual correcting it.

Conserving electricity can be done again by now make all the orbital manouvres with SAS not constantly on, just notch the craft in the direction you want, hold F to temp disable SAS, then release it near the point where you want it..

Chutes can be released at 21km height and act as counter balance if you out of electricity and keeps the pod with the shield facing fowards, and will not be burned by the heat, and it wont be ripper off (havent at least managed that yet to happen)..

Other way that works fine, is the steep/drop down way, you will go down with an insane speed, but you go so fast the heat buildup just wont have time enough to get too high before it starts to cool off again, but the chute wil hold with these extreme landings, and maybe is even easier to do for a new player since getting it at KCS that way is pretty easy, thus saving big costs on recovery.

Its different now with Heat/Drag added and its not like FAR/NEAR/DE its different, and it took a very little time for me to adjust.. (very little even) but granted my old ways didnt worked, so i looked for ways that did work..

Link to comment
Share on other sites

I had an interesting reentry from the first orbital flight... Did a Mun-shot had stuff with science... stuff fell off when ended up pointing prograde. Now going back to Mun with Valentina (she was supposed to be the first to orbit but auto-crew fill...). I put a heatshield on top with a decoupler and nose cone. And only now when I'm EVA'ing to get the science from the materials bay... Should've done that the first time and disposed of it all. For now I'll just add heatshields to everything. Also took me something like 7 or 8 aerobrakes with a c.44km PE coming home from the Mun.

Link to comment
Share on other sites

I had an interesting reentry from the first orbital flight... Did a Mun-shot had stuff with science... stuff fell off when ended up pointing prograde. Now going back to Mun with Valentina (she was supposed to be the first to orbit but auto-crew fill...). I put a heatshield on top with a decoupler and nose cone. And only now when I'm EVA'ing to get the science from the materials bay... Should've done that the first time and disposed of it all. For now I'll just add heatshields to everything. Also took me something like 7 or 8 aerobrakes with a c.44km PE coming home from the Mun.

Yeah, I've gotten so used to FAR. The top of the atmosphere is soooo thin. I did the same thing with a Mun flyby. Turned a 2 days mission into a 10 day mission.

Flippiness has definitely happened with SAS off. Not sure how I'm going to get probes home without SAS.

Link to comment
Share on other sites

This. Seriously. Opening a chute...in space?!?! And it does not rip and it does not burn?

No, it doesnt ! Activate it in space just before re entry, fall into the atmosphere, and as soon as it goes off (around 21Km iirc), not even fully deployed, the chute doesnt burn, doesnt tear apart, you get crazy g´s and BOOM you're a going at 300m/s at 18Km alt. It just negates the re-entry !

(i can only talk for LKO so far.)

Link to comment
Share on other sites

For anyone that has issues with reentry.. maybe this pic will help you understand.. the capsule wants to do the following:

https://www.dropbox.com/s/ayomiv2uaxq3wj3/reentry.png?dl=0

Just like Apollo did.. now, ofc if you are piling up stuff on top, that MAY not going to work very well.

Apart from that, i admit, the shield having no mass does make it a bit awkward. But the capsule itself (same as in that picture) is extremely stable during reentry in that position.

Edited by DJK
Link to comment
Share on other sites

I still think this is way broken. Blunt body capsules are made that way because they are aerodynamically stable, they will turn the blunt part to retrograde and stay in that direction. Gemini used small RCS thrusters to use the capsule as a lifting body, thereby fine-tuning where they landed. Having a blunt body which wobbles like cah-razy is just...plain wrong, IMNSHO.

Link to comment
Share on other sites

As people have been pointing out, putting a very light, very draggy materials bay under your heavy pod is like trying to balance a dart on your palm...feathers first. Or trying to throw a dart feathers first. Guess how well that will work. :P

It's true that stock isn't as good at modeling body lift as FAR is (though it's also true stock does model it), so that makes these sorts of things less stable than they might be, but you _do_ have to observe some sanity in your reentry vehicles.

ola: as the thread has been pointing out, capsules are stable. It's when you add very large very light things on their bottom, they become unstable.

Link to comment
Share on other sites

It stabilizes with the mk1 pod with the side of the capsule down, NOT the heat shield. It never rights itself. Capsule, parachute, heat shield, and 1 antenna, opposite the hatch (near the top, tilted so that even deployed it is 100% shielded by the base of the capsule).

Never rights itself, then explodes at maybe 16k m. I reentered from LKO (~75k).

Link to comment
Share on other sites

I had an interesting reentry from the first orbital flight... Did a Mun-shot had stuff with science... stuff fell off when ended up pointing prograde. Now going back to Mun with Valentina (she was supposed to be the first to orbit but auto-crew fill...). I put a heatshield on top with a decoupler and nose cone. And only now when I'm EVA'ing to get the science from the materials bay... Should've done that the first time and disposed of it all. For now I'll just add heatshields to everything. Also took me something like 7 or 8 aerobrakes with a c.44km PE coming home from the Mun.

With the old DRE + FAR stack you usually aimed towards the 32K-29K corridor. Anything below went kaboom, anything above went bouncy-bouncy.

Link to comment
Share on other sites

I always jettison my science before reentry. It didn't help. I turned off SAS and off I went. Turned SAS on and the capsule (Just the standard SAS, not hold retro or anything.) did its dance and drained battery. It was just 3 parts, the capsule, the heat shield, the parachute. Some people seem to get some stability so I am not sure why I am not. It seems to me that this needs tweaking.

It is a clean install right from the steam folder. Later on when the mods are ready I will copy-pasta to my normal game folder and run from there leaving my steam folder pristine.

Link to comment
Share on other sites

As people have been pointing out, putting a very light, very draggy materials bay under your heavy pod is like trying to balance a dart on your palm...feathers first. Or trying to throw a dart feathers first. Guess how well that will work. :P

It's true that stock isn't as good at modeling body lift as FAR is (though it's also true stock does model it), so that makes these sorts of things less stable than they might be, but you _do_ have to observe some sanity in your reentry vehicles.

ola: as the thread has been pointing out, capsules are stable. It's when you add very large very light things on their bottom, they become unstable.

Nathan, I am testing JUST the capsule, Mercury style, I don't reenter science parts.

Link to comment
Share on other sites

As people have been pointing out, putting a very light, very draggy materials bay under your heavy pod is like trying to balance a dart on your palm...feathers first. Or trying to throw a dart feathers first. Guess how well that will work. :P

It's true that stock isn't as good at modeling body lift as FAR is (though it's also true stock does model it), so that makes these sorts of things less stable than they might be, but you _do_ have to observe some sanity in your reentry vehicles.

ola: as the thread has been pointing out, capsules are stable. It's when you add very large very light things on their bottom, they become unstable.

Sorry, I'm just slightly aggravated at the moment.

Link to comment
Share on other sites

The capsules by themselves are relatively stable. The issue is when sticking things underneath them. Mk3 + Service module (contains science galore) + Heat shield, this is the obvious assembly method, is capable of reentry by itself, but requires SAS to hold steady, and WILL flip once it reaches the lower atmosphere. It's slowed enough by that point that it isn't burning, but it's a decent illustration of the problem.

Would reducing the mass of the capsule and making the heat shields heavier help with stability? I'm still not entirely clear on the new aero.

Link to comment
Share on other sites

This rode to destruction, stable, in this position from LKO. I started with it pointed perfectly retrograde. Perhaps I need even less on this "crazy" capsule design? What can I do without? The chute?

reentry.jpg

Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...