About planned re-entry heating:

[UNSC]

I agree, command pods should have the option for a built in heat shield, with added weight of course.

[MR4Y]

I don't think there should be a toggle to completely turn it off, but have different difficulty modes like easy, medium, hard with different levels of heating. Also MR4Y how could adding heat shields increase part count 2-4 times? Its not like your covering every single piece. I'm sure there will be large inflatable heat shields that's one part that can cover large craft

I was mentioning if heat decals where added, which is something better than an inflatable heat shield, that would end up affecting aerodynamics and flip your rocket, like happens on Deadly Reentry, leaving you hopeless because you have almost zero control over the rocket while it reenters.

[Albert II]

Im playing now with "Deadly Reentry" mod and wouldn't play without it so bring on the heat.

[DevoidLight]

I wonder if it will be possible to build a ship fast enough that it burns up before you even leave the atmosphere on take off?

[PakledHostage]

In the case of aerocapture, you're dissipating large amounts of energy. Most of that energy is converted into heat. Whether that heat is damaging would depend on how well shielded your craft is.

I thought I'd add some rough numbers to put this statement into perspective:

- Difference in kinetic energy between a spacecraft at Kerbin escape velocity from LKO (~3300 m/s) and LKO orbital velocity (~2200 m/s) is about 3 million Joules per kg of spacecraft mass.

- About 1000 Joules is all you need to heat 1 kg of sea level air by 1°C

- About 900 Joules is all you need to heat 1 kg of room temperature aluminum by 1°C

You need to dissipate a minimum of 3 million Joules per kg of spacecraft mass to enter LKO from interplanetary space. If you use the atmosphere to slow you down, you're going to heat up.

Obviously, the role of a heat shield is to prevent that massive amount of energy from heating the spacecraft. How it does that is complex and doesn't need to be modeled in the game, but clearly there should be consequences for performing an aerocapture maneuver (or a landing) without one.

[asmi]

I just don't get the point of this discussion. Players who wants the "god mode" will unlikely stay in KSP for long as these challenges adds playability. Current reentry mechanics are somewhat equivalent to requesting a feature that would allow you to turn on engine and after certain amount of fuel is spent, you're in orbit - no need to worry about orientation, piloting, etc. If you don't like it and think that piloting should matter - then I don't see why whould you be against reentry heat as it's just one more variable that you have to take into account during building of a spacecraft. My example above demonstrates what current situation is like - if during reentry you can just take your hands off keyboard/joystick and relax, why can't you do that during ascent? Both are equally utterly unrealistic, both don't make any sence, yet some players are asking for the former, but no one - for the latter.

Oh, and in regards to heat during ascent - in most cases you're simply not moving fast enough during ascent to heat up, but if you'll stick to stupid "MOAR BUSTERZ" concept you can theoretically burn up. Also reentry heat will likely come with improved aerodynamics and so more aerodynamic shape of the vehicle will help to reduce heating.

[MR4Y]

I just don't get the point of this discussion. Players who wants the "god mode" will unlikely stay in KSP for long as these challenges adds playability. Current reentry mechanics are somewhat equivalent to requesting a feature that would allow you to turn on engine and after certain amount of fuel is spent, you're in orbit - no need to worry about orientation, piloting, etc. If you don't like it and think that piloting should matter - then I don't see why whould you be against reentry heat as it's just one more variable that you have to take into account during building of a spacecraft. My example above demonstrates what current situation is like - if during reentry you can just take your hands off keyboard/joystick and relax, why can't you do that during ascent? Both are equally utterly unrealistic, both don't make any sence, yet some players are asking for the former, but no one - for the latter.

Oh, and in regards to heat during ascent - in most cases you're simply not moving fast enough during ascent to heat up, but if you'll stick to stupid "MOAR BUSTERZ" concept you can theoretically burn up. Also reentry heat will likely come with improved aerodynamics and so more aerodynamic shape of the vehicle will help to reduce heating.

Some planes, if engineered right, can break Mach 1 before leaving the thick atmosphere. Now imagine them trying to break the reentry layer and exploding. Rockets won't have enough speed to overheat in take off, but SSTO's and space planes do.

[Comrade Jenkens]

re entry heating was probrably always planned to come eventually. We've just grown soft in its absense.

[PDCWolf]

Rockets won't have enough speed to overheat in take off, but SSTO's and space planes do.

Not really, since the real-life concept for SSTO with nowadays non-experimental technology will be to go as high as possible with jet engines and then start your rockets, not reaching orbital speeds while in atmosphere as our SSTOs do, which in real life is just stupid (look at x43 and x51, they just go for 30 seconds and then burn themselves to pieces).

About reentry heat, it'll obviously add a layer of realism to the actual game that lacks it a lot (I mean, come on, don't even try to think KSP is realistic in its actual state).

About reducing the reentry heat, you just need to enter at less angle, a good practice is putting your periapsis at 55 km and place it around 170km before your actual landing target (this is talking with an apoapsis of 70/75km) and that should solve all your heating problems.

[asmi]

Some planes, if engineered right, can break Mach 1 before leaving the thick atmosphere. Now imagine them trying to break the reentry layer and exploding. Rockets won't have enough speed to overheat in take off, but SSTO's and space planes do.

In real life planes don't burn at Mach 1. Infact at speeds up to Mach 3-5 the driver for the design is structural stress, not heating. Only when you go to hypersonic speeds the heating becomes a concern. Vast majority of SSTO planes speed up when they are in upper atmosphere, so while heating can be a problem there, it can be managed by protecting areas that are going to be exposed to airstream. Remember that hypersonic airstream has VERY different properties and behavior then slow subsonic one.

[PakledHostage]

About reducing the reentry heat, you just need to enter at less angle...

In the real world, entering at too shallow an angle can actually cause you to burn up too. The reason is that both the magnitude of the heat flux and the length of exposure are a problem. You can see the consequences of entering at too shallow an angle in the top-right corner of the plot in my post on page 3 of this thread.

It doesn't take a very sophisticated re-entry heat model to simulate that effect either. It would be nice if it is implemented.

[allmappedout]

Some planes, if engineered right, can break Mach 1 before leaving the thick atmosphere. Now imagine them trying to break the reentry layer and exploding. Rockets won't have enough speed to overheat in take off, but SSTO's and space planes do.

Just cause you can do something doesn't mean it's a good idea!

[magnemoe]

I just don't get the point of this discussion. Players who wants the "god mode" will unlikely stay in KSP for long as these challenges adds playability. Current reentry mechanics are somewhat equivalent to requesting a feature that would allow you to turn on engine and after certain amount of fuel is spent, you're in orbit - no need to worry about orientation, piloting, etc. If you don't like it and think that piloting should matter - then I don't see why whould you be against reentry heat as it's just one more variable that you have to take into account during building of a spacecraft. My example above demonstrates what current situation is like - if during reentry you can just take your hands off keyboard/joystick and relax, why can't you do that during ascent? Both are equally utterly unrealistic, both don't make any sence, yet some players are asking for the former, but no one - for the latter.

Oh, and in regards to heat during ascent - in most cases you're simply not moving fast enough during ascent to heat up, but if you'll stick to stupid "MOAR BUSTERZ" concept you can theoretically burn up. Also reentry heat will likely come with improved aerodynamics and so more aerodynamic shape of the vehicle will help to reduce heating.

Pods already have an heat shield, we will get heat shield to put on other items, however we will probably need mods to get the huge ones to protect large ships depending on design

For this ship something in front over the landing can cockpit, an wider one below to protect the 3.75 meter home modules, then smaller shields to protect the front of the engines. I would lose the forward docking port at least during aerobraking.

Another option would be an huge 10 meter inflatable shield in front' this would let me dock stuff on the sides behind it.

Some chance we get two types an light one for one time use and an heavier one who can be reused like on the shuttle.

I do not see this as an huge issue, except that it will make existing ships unable to aerobrake.

[Technical Ben]

It will have to be part of my designs for aerobraking interstellar craft. Will have to think it through, but should be possible.

[astocky]

I really don't like the current deadly reentry mod because it teaches really bad habits. People are starting the think that a 100km x 45km orbit is a good way to reenter, where in fact you want more like a 100km x 0km to ensure that you slow down before you heat up too much and explode.

PakledHostage has done some really good work complete with graphs that show how it should work. If you want to test it, try and set up a reentry that gives you 4 g's of deceleration (perfectly reasonable for a real capsule) and you will find for the Kerbin atmosphere it is a very steep reentry.

I wonder is someone can make a plugin that changes the reentry heat effects?

[Awaras]

This looks promising: http://forum.kerbalspaceprogram.com/showthread.php/32342-Deadly-Reentry-2-0-Release-Candidate-1-in-need-of-testers%21

[PakledHostage]

ialdabaoth's revision to r4m0n's mod does look promising. I'm willing to offer ialdabaoth the code from my old re-entry heat plugin too, but I'm afraid that it would just lead to confusion and complaints among users of such a mod. The old re-entry heat plugin would have spacecraft being destroyed long before the visual effects are displayed.

Edited May 28, 2013 by PakledHostage

[Daze]

I think that it will be 10 times more funny to make ship...

[magnemoe]

It will have to be part of my designs for aerobraking interstellar craft. Will have to think it through, but should be possible.

"interstellar" ships travel between stars, 5% of light-speed or faster, you do not want to aerobrake them

Done in one of the Man Kizin books, however they used an device who made the ship invulnerable and aerobraked in an suns atmosphere after beeing dropped by an bussard ramjet.