Longer re-entry

[Cheif Operations Director]

I know this may be difficult  to do, but the re-entries are WAY to fast. Consider this... I can launch an ICBM and when the warheads hit the ground they are going  20 m/s Due to the resistance. When I come back from the mun the craft hits the atmosphere as soon as it lights up it's only Maby 28 seconds before I'm at 200 m/s. I just came from 3,000 m/S that's a change of 2,800 m/S in 28 seconds or 100 m/s per second being lost. This is just your average capsule not some massive drag creating machine. It would be nice if you actually had to do wait just a bit  during re-entry. I could and HAVE landed a space craft by just letting it fall down due to the drag. 

[Rocket In My Pocket]

Why would you want to make a non-interactive part of the game any longer?

I already do them at x4 speed, because I've seen enough Capsules fall to the ground to last me a life time lol.

I'm just not sure what the appeal of watching it for longer than you have to would be?

[JadeOfMaar]

A couple of factors are in play here and easily observed:

• The command pods can take a lot of heat, likely without a heatshield under them.
• Your Kerbin periapsis may be quite low, encouraging exponentially higher drag and faster deceleration. If an IRL re-entry vehicle came down straight from the Moon, I'm sure it would do several passes with high Periapsis and aerobrake very gently as, unlike kerbal, we're very sensitive to air pressure and blazing hot plasma.
• Everything is relatively quick and easy and safe at stock scale. Install Sigma Dimensions and Rescale! and inflate your universe, then see if your question is still valid.

Edited September 15, 2018 by JadeOfMaar

[Gargamel]

16 minutes ago, JadeOfMaar said:

If an IRL re-entry vehicle came down straight from the Moon, I'm sure it would do several passes with high Periapsis and aerobrake very gently as, unlike kerbal, we're very sensitive to air pressure and blazing hot plasma.

IIRC, Apollo did do a direct return from the moon, without any extra orbit's around the Earth. 

 

Gameplay, for the most part, is dictated by the laws of physics established within the KSP universe.   That's the whole point of the game.  It should not be modified based on what feel's right or looks good.   That's where unbelievable and crap games come from.   I don't want Micheal Bay anywhere near my game.    The atmosphere is only so thick, and you are going really fast.   Mixed with atmospheric density curves, you will, by law, hit certain speeds after certain amounts of time.   The trade off is G forces.   Humans are far less tolerant of high G loads than Kerbals.  If there is no ill effect on a kerbal, why bother adjusting a reentry profile? 

The laws of KSP physics were written to balance out the game.  They inadvertently ended up making a few concessions, one of which is a 'simplified' re-entry profile for landing on Kerbin.  If they made changes to this, it would have consequences far reaching throughout the game.  Planes would fly completely differently, if you remember the pre-1.0 soup-o-sphere.   Launch profiles would have to be redone, which means common rocket designs would go out the window.   It would probably affect atmospheric density curves on other planets too, completely nixing current mission profiles. 

Changing the laws of physics to make something 'feel' better won't be a good thing. 

 

 

[KerikBalm]

You can lower the drag multiplier. Stock craft are pretty draggy. If you look at real jet engines, their thrust is often significantly lower than what KSP jets produce (but not orders of magnitude), the catch is that KSP jets need more thrust for a given speed.

So... yea, KSP's atmosphere is a bit draggy. As for the ICBM warhead... I don't know what you use as a warhead, but warheads are pretty heavy, and there aren't that many really dense parts in KSP, so 20 m/s is fine as a terminal velocity for something like just the pointed nose cone.

I use sigma dimensions to rescale kerbin 3x (but the atmosphere only 1.25x), and reentries do indeed take longer because my craft come in from abotu 4,100 m/s orbital velocity, not about 2350 m/s... and reentry heating is actually an issue

[Mr. Peabody]

No no no. This is a terrible idea. Imagine what it would do crafts that re-enter without heat-shields? It's already complicated enough.

[Starwaster]

@JadeOfMaar, @Gargamel is largely correct. Apollo did not reenter in several passes though it did perform what is referred to as a 'skip' reentry where it would fly back out of the atmosphere very briefly and then plunge back in. This was controlled by rolling the pod to direct lift.

G-forces for lunar return missions ranged from 5G-7G. 

The Genesis probe sample return pod performed a ballistic reentry that exceeded 30 G's. (it also returned direct without multiple passes into the atmosphere)

[OhioBob]

On ‎9‎/‎15‎/‎2018 at 2:22 PM, Cheif Operations Director said:

I know this may be difficult  to do, but the re-entries are WAY to fast. Consider this... I can launch an ICBM and when the warheads hit the ground they are going  20 m/s Due to the resistance. When I come back from the mun the craft hits the atmosphere as soon as it lights up it's only Maby 28 seconds before I'm at 200 m/s. I just came from 3,000 m/S that's a change of 2,800 m/S in 28 seconds or 100 m/s per second being lost. This is just your average capsule not some massive drag creating machine. It would be nice if you actually had to do wait just a bit  during re-entry. I could and HAVE landed a space craft by just letting it fall down due to the drag. 

Dude, what kind of entry angle are you coming in at?  You're averaging 10g on a return from Mun?  No wonder your reentries go by in the blink of an eye.  There's nothing wrong with the game, I think you're just coming in way too steep.  Shallow your entry angle and you'll decelerate more slowly, and the reentry will last longer.

For a return from Mun, I generally like a trajectory that has a periapsis altitude of about 20-25 km above Kerbin.  This usually generates a peak deceleration of about 3.5g.  And the reentry takes several minutes.  Set the periapsis to 35 km and the reentry can last a very long time.

[Gargamel]

7 hours ago, OhioBob said:

For a return from Mun, I generally like a trajectory that has a periapsis altitude of about 20-25 km above Kerbin.  This usually generates a peak deceleration of about 3.5g.  And the reentry takes several minutes.  Set the periapsis to 35 km and the reentry can last a very long time.

That's a really good point Bob.  I missed the core issue here, forest for the trees type thing.   Quoting for emphasis, as you're exactly right, this is probably the main issue.   I too would feel reentry would be too quick if I slammed down into the atmo at steep enough angle.  I'd also have to change my shorts more often.

[KerikBalm]

So.... increase the reentry heat multiplier, and adjust reentry steepness accordingly is the answer (also... use a rescale mod to make kerbin bigger)

[Thygrrr]

You are coming in too steep!

 

Increase reentry heating to 120% or more (I like 150% - every reentry takes full attention), and also reduce Kerbal G tolerance. A 10g entry should at least make them pass out, or kill them.

 

Together with plasma blackout, you would reenter either at an oblique angle, or crash.

 

Solved. (Btw this is how I play)